Surface Drilling

Surface Drilling in Open Pit Mining

First edition 2006 www.surfacedrilling.com

www.rcb2.se

Thinking young takes practice

Working with Atlas Copco gives you access to more than a century of rock drilling innovation. It ensures that you work with a solutions provider who delivers the best-performing systems, products, and people available – today and tomorrow. Our success in construction and mining is based on the combination of young minds and long experience. Get your free copy of Success Stories at www.atlascopco.com/rock Committed to your superior productivity

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Contents Foreword     2 Foreword by Markku Terasvasara, Vice President Marketing Surface Drilling Equipment at Atlas Copco Rock Drills AB

 Talking Technically     3 Open Pit Mining     7 Principles of Rock Drilling   10 Principles of Rock Blasting   12 Putting Rotary Drilling Into Perspective   15 SmartRig Takes Control   17 Correct Selection of Tophammer Rock Drilling Tools   20 COPROD Combines the Best of DTH and Tophammer Drilling   25 Increased Productivity with DTH Drilling   28 Selecting the Right DTH Drilling Tools   34 Economic Case for Routine Bit Grinding   38 Ergonomics & Safety   41 Rotary Club Expands With Thiessen   42 In Search of the Right Balance   45 Protection by ROC Care

  Case Studies A Viper for the Copper King Best Practice at Bingham Canyon Rotary and DTH Work Side by Side The Golden Twins of Southern Mexico Minera Maria’s Pre-Split Pioneer ROC L8 Gains Favour in Brazil Hydraulic Tophammers Exceed Soquimich Expectations   67 Winning Iodine from the Atacama Desert   47   49   51   54   58   61   65

  69 Replacing Rotary in Iron Ore   70 Multiple Tasking in Western Australia   73 ROC L8 Outperforms in Assmang Iron Ore   74 Greater Geita   78 DTH Choice Cuts Costs at Navachab   80 Iron Ore From Erzberg Mountain   82 More Than a Match for Scotland’s Coal   84 Apatite for Extraction – Coprod Solution for Siilinjärvi

  Product Specifications   88 Drilling Method Guide   90 Tophammer Drill Rigs   97 Tophammer Rock Drills   99 Tophammer Drilling Tools 110 COPROD System 111 COPROD Crawlers 114 COPROD Drill Rigs 115 COPROD Drilling Tools 118 DTH Drill Rigs 124 DTH Hammers 126 Rotation Units 127 Rotary Drill Rigs 131 Secoroc Tricone Bits 133 Secoroc Grinding 138 Drill Rig Options 147 Service Workshops 148 Conversion Table

Front cover: Blasting time at Aitik Copper Mine in Sweden. SmartRig, COPROD, ROC and COP are Atlas Copco trademarks. Atlas Copco reserves the right to alter its product specifications at any time. For latest updates contact your local Atlas Copco Customer Center or refer to www.surfacedrilling.com

Produced by tunnelbuilder ltd for Atlas Copco Rock Drills AB, SE-701 91 Orebro, Sweden, tel +46 19 670-7000, fax –7393. Publisher Ulf Linder [email protected] Editor Mike Smith [email protected] Senior Adviser Hans Fernberg [email protected] Picture and Specifications Editor Lisa Boyero [email protected] Contributors Alf Stenquist, Bo Persson, Brian Fox, Göran Nilsson, Gunnar Nord, Hans Fernberg, Jan Jönsson, Jean Lindroos, Jessis Ng, Joanna Jester, Leif Larsson, Lennart Lundin, Lennart Söderström, Lorne Herron, Mathias Lewen, Therese Blomster, all [email protected], Adriana Potts [email protected], Maurice Jones [email protected] Designed and typeset by ahrt, Örebro, Sweden. Printed by Welins Tryckeri AB, Örebro, Sweden. © 2006 Atlas Copco Rock Drills AB

Drilling in open pit mining

Copies of all Atlas Copco reference editions can be ordered in CD-ROM format from the publisher, address above, or online at www.atlascopco.com/rock. Reproduction of individual articles only by agreement with the publisher.



Foreword

T

 o be perceived as the global market leader in providing rock drilling products, it is important that our product and service offering has the competitive edge: that we can assist our customers to generate high profit leading to business expansion. Our growth is a consequence of our customers’ success. We have also grown by making strategic acquisitions such as the drill rig division from Ingersoll Rand, and by launching new, efficient products and aftermarket programmes during the past five years. Today, our range of drill rigs comprises more than 40 models suited for various surface drilling applications. Our modern products are equipped not only with key components such as powerful rock drills, engines, pumps and compressors, but also with the latest computer based technology. We have never before been committed to such a dynamic and intensive product development, giving a whole new dimension to quality and productivity in terms of directing and guiding the equipment to perform drill holes as close as possible to plan, to planned depth and hole bottom locations. This is a prerequisite for optimum fragmentation of blasted rock, even benches and rock wall contours. High productivity, as a result of outstanding equipment availability and drilling capacity, leads to better utilization of the investment. Our long-standing relationship with Secoroc has allowed us to develop drill string components, bits, and high pressure DTH hammers to match the potential of our rock drills and rigs, together with bit grinding to maintain high performance with economy. The second generation of Coprod for straighter small-diameter holes is a prime example of how successful this partnership has been. Our new computer based rigs are known as the SmartRig concept, emphasizing that they have incorporated state-of-the-art functionality, making them easy to use and maintain. Additionally, we have spent a lot of effort in providing a good working environment inside the operator’s cabin. We trust that this book, presenting not only our current product offering, but also some examples of best practice at selected operations, will stimulate technical interchange between people having an interest in surface drilling in open pit mining. Those engaged in mining projects, technical consultancy, universities and our own sales and marketing efforts should, hopefully, find a lot of valuable reading material.

Markku Terasvasara

Vice President Marketing Surface Drilling Equipment [email protected] 

Drilling in open pit mining

Talking Technically

Open Pit Mining Finding the Best Combination Large quantities of raw material are produced in various types of surface operations. Where the product is rock, the operations are known as quarries. Where metallic ore or non-metallic minerals are involved, they are called open pit mines. There are many common parameters in design and choice of equipment, and in the process of finding the best combination of drilling and blasting methods. Atlas Copco has the advantage of long experience in all types of surface drilling operations, with a product range to match. With its history of innovative engineering, the company tends to think forward, and is able to advise the user on improving design elements of the operation that will result in overall cost savings.

Surface or Underground Mining Mining carried out underground can follow and be tailor-made to suit the mineralization zones on a selective higher metal content basis, thereby minimizing the amount of waste rock, which has to be extracted. The amount of ore to be left behind varies depending on mining method between 10-35 percent. Waste to ore ratio is typically 1 to 4.   As no orebodies have the perfect conical shape, vast quantities of waste have to be removed from both the hangingwall and the footwall to get access to the ore as it progresses in depth. Waste to ore ratio varies extensively depending largely on the geometry of the orebody. Many open pit operations excavate more than 5 times the amount of waste compared to ore. Figure 1 shows a sectional layout of a typical pit. The waste to ore ratio increases as the pit gets deeper. Eventually, for Drilling in Open Pit Mining

Figure 1 General principles of open pit mining.

economic reasons, the open pit will be abandoned, or underground mining will take over.   As the ore, compared with underground mining, is more diluted and intermixed with waste and lower grade ore, crushing, screening, milling, flotation etc need high capacity. As mining progresses at depth large quantities of side rock have to be excavated in stages, so called pushbacks. See fig. 2 Aitik.

Open Pit Mining A typical work cycle in an open pit mine consists of a number of work elements. Exploration drilling is conducted to define ore boundaries for future planning. This is commonly combined with in-pit reverse circulation drilling to confirm the mineral contents, which is important for optimizing the blasting and the mineral processing. Drilling of blastholes is undertaken in

Figure 2 Aitik open pit mine. Hangingwall extractions in stages..

orebody



Talking Technically

Decking 6 m

Pipe charge 6,5 m Production holes Ø 315 mm Bottom charge 4 m

1 tonnes explosives/hole Two Boosters

Optimum Fragmentation and Pit Geometry

Figure 3 Charging the blast holes at Aitik.



where blasts are restricted to a couple of ten thousand tonnes. The individual holes and the rows are delayed with short intervals to get good swell for efficient loading.   Before loading, the lower pit floor

Without jeopardizing slope stability, it is of prime importance to keep the pit slope angle as steep as possible, maintaining excavated waste at a ­minimum.   The demands on fragmentation of the waste, as it will not pass through the

Figure 4 Charging the blast holes at Aitik. Metso Minerals.

Boulders Fragment elongation

Quantity

a predetermined pattern, followed by plugging the drill holes with wooden or plastic plugs to prevent debris from falling down into the holes.   When an adequate number of holes have been drilled, preparations for blasting will start. The holes are blown clean with compressed air to remove water and rock fragments, and are then charged with booster bottom charges, detonators and explosives. Stemming (decking) is inserted into the top of each hole, and the detonator leads are connected. Where electric detonators are used, the circuit resistance is checked with an ohmmeter. See fig. 3 charging the blast holes at Aitik   The area is ­ evacuated, equipment is moved away, and the round is fired. The size of blasts in an open pit is normally much larger (up to a couple of million tonnes) compared to a quarry

is cleaned of fly rock with a wheel loader. Blasted rock is then loaded and removed with huge sized equipment such as drag line bucket loaders into trucks, and transported to the crusher station. Large boulders are pushed aside, and stockpiled for subsequent secondary breaking. Rock is discharged directly, or via a grizzley for size control, into the primary crusher. Thereafter, it is transported by conveyor belts for secondary, and possibly tertiary crushing.   The different products, comprising rock fragments of certain size ranges, are recovered from the process by vibrating screens, and transported to storage silos or bunker piles on the ground.   A major difference between open pit mining and quarries is the geological conditions and the demand characteristics on the blasted material. Whereas quarries deliver the majority of rock via the crushing and screening plant in various size fractions, the open pit mine attempts to deliver the ore as pure as possible via crushers to the dressing plant, consisting of mills, separators, and/or flotation, and/or biochemical systems, and finally to smelters, in order to convert minerals to metals.

% fines in blast Micro cracks in fragments

Drillhole diameter Drilling in Open Pit Mining

Talking Technically

depth of 1,000 metres saves a staggering 150 million metres of rock excavation by just making the pit slopes one degree steeper. Consequently there are large savings to be made if drilling and blasting is carried out in an optimum way.

Drilling Patterns and Type of Drill Rigs

Figure 5 Drilling pattern for presplit in open pit mining.

crushing/dressing system, are simple. It should merely suit the loading and trucking equipment used for subsequent removal to the waste dump. On the other hand, good fragmentation of the blasted ore will make great savings in the total costs of the mineral dressing process. By contrast to quarries, where the fines fraction are regarded as reject (especially at aggregates), open pits delivering ore to the dressing plant get savings in the disintegration process in case high amount of fines are present. Large holes generate a higher spread of size distribution from more boulders to higher amount of fines-see fig. 4   Blasting will not only break the rock that is planned to be excavated, but

will also cause damage to the slopes that form the boundaries of the pit. The extent of this overbreak is mainly dependent on the size of the individual charge and its proximity. A common means of minimizing overbreak is to use smaller diameter holes, making provision for restricted blasting in the zone next to the planned bench slope. Figure 6 shows two different blast designs.   Figure 5 shows a typical drilling pattern to be applied in connection with pre-split blasting, to achieve increased slope stability with reduced back break. The huge Chuquicamata open pit (production rate 650,000 tonnes per day) in Chile being 8 km long and 2.5 km wide and progressing towards a final

Traditionally, focusing on the drilling cost parameter and productivity only, the predominant method in open pit mining is large hole rotary drilling using hole sizes in the 250 to 400 mm (10-15.75 in) range. No doubt this implies lower cost for drilling, ignoring the expense of excess waste, more explosives and less controllable fragmentation. A survey of 36 open pit operations in Chile using hole sizes between 75 and 345 mm (3.0-13.75 in) reveals that hole sizes above 200 mm (8 in) do not generate any substantial savings in total drilled metres per tonne. This indicates that burden and spacing cannot be increased indefinitely. One important reason for replacing rotary with other methods is the inflexibility of the heavy rotary rigs, which are restricted to vertical benches and single pass drilling only.   Figure 6 shows the advantages related to using an Atlas Copco ROC L8 rig, having the ability to drill inclined holes close to the bench wall, compared to a traditional rotary rig. The best combination of drill rigs might well Figure 6 Savings in waste extraction by increasing the pit slope.

Drilling in Open Pit Mining



Talking Technically

Figure 7 Drill pattern at Aitik open pit, Sweden.

Production holes 315 mm 8-9 m drillpattern 15+2 hole depth

2 rows 140–165 mm

Figure 9 Charging for soufflé blasting.

Figure 8 Soufflé blasting at Björkdal gold mine.

prove to be large rotary rigs for waste rock and high productivity in the pit centre coupled with flexible DTH rigs for selective mining, pre split of slopes as well as for in-pit grade control drilling. See fig 7 Aitik.

Soufflé Blasting Mining of rich, narrow and irregularly stratified ore zones, such as gold mineralizations, requires extra attention, in order not to introduce unnecessary 

quantities of waste into the ore stream. Con­sequently, this type of mining has to be progressed on a selective basis, in close liaison with surveyors and geologists, by taking frequent samples before and after each individual blast. Short benches and small holes are used to cope with ore zone irregularities. A recently-developed method to ensure maximum recovery from each blast is called soufflé blasting. Figures 8 and 9 illustrate this ­ principle of cautious blasting with a ­minimum of dilution as

practised at the Björkdal gold mine in Sweden. To a depth of merely 5 m, 100 vertical holes are blasted in one round, without free surface for ex­pansion. The firing sequence starts in the centre and, thanks to 2.5 m of stemming, the blasted ore material just swells on site like baking a soufflé. Selective extraction by backhoe ­ loaders facilitates maximum recovery of the rich, narrow gold-bearing zones.

by Hans Fernberg Drilling in Open Pit Mining

Talking Technically

Principles of Rock Drilling Drilling for Excavation by Blasting This reference edition deals with surface rock drilling used for the purpose of excavating rock in quarries and construction projects by means of blasting. Other types of drilling, such as for oil and water, mineral exploration and exploitation, and grouting, are excluded. The reader is given a brief explanation of prevailing drilling methods, together with an introduction to blasting techniques and the interrelation of drilling and blasting. Also discussed are the main parameters involved when planning and executing blasthole drilling at quarries and civil engineering projects. The range of Atlas Copco products, with references to the Atlas Copco websites, are presented and discussed by comparing their suitability and expected productivity related to a selection of applications. Case studies from worksites around the world should prove interesting and beneficial, especially when planning and selecting methods and equipment for blasthole drilling applications. Blastholes have certain unique and important characteristics. These are: hole diameter, depth, direction, and straightness. Drilling produces a circular hole in the rock, the strength of which must be overcome by the drilling tool. Depending upon rock properties, there are several ways to accomplish this, as shown in the following article.

Rotary Drilling Rotary drilling can be subdivided into rotary cutting and rotary crushing. Rotary cutting creates the hole by shear forces, breaking the rock’s tensile strength. The drillbit is furnished with cutter inserts of hard metal alloys, and the energy for breaking rock is provided by rotation torque in the drillrod. This technique is limited to rock Drilling in open pit mining

Figure 1 Principle of tophammer drilling.

with low tensile strength, such as salt, silt, and soft limestone not ­ containing abrasive quartz minerals. Rotary crushing breaks the rock by high point load, accomplished by a toothed drillbit, which is pushed downwards with high force. The bit, being of tricone roller type fitted with tungsten carbide buttons, is simultaneously rotated, and drill cuttings are removed from the hole bottom by blowing compressed air through the bit. Drillrigs used for rotary drilling are large and heavy. The downwards thrust is achieved by utilizing the weight of the drillrig itself, and the rotation, via a hydraulic or electric motor, applied at the end of the drill pipe. Common hole dia­meters range from 8 to 17.5 in (200-440 mm) and, because adding the heavy drill pipes is cumbersome, most blasthole drillrigs use long masts and pipes to accommodate single-pass drilling of maximum 20 m (65 ft). Electric power is usually chosen for the large rigs, whereas smaller rigs are often powered by diesel engines. Rotation rates vary from 50 to 120 rev/min, and the weight applied to the bit varies from 0.5 t/in of bit ­diameter in soft rock, to as much as 4 t/in of bit diameter in hard rock. Recent technical advances include: improved operator cab comfort; ­automatic control and adjustment of optimum feed force and rotation

speed to prevailing geology and bit type and diameter; and incorporation of the latest technology in electric and hydraulic drive systems. Rotary drilling, which is still the dominant method in large open pits, has limitations in that the rigs are not suited to drilling holes off the vertical line. As ­ blasting theories and practice have proved, it is generally beneficial to design, drill and blast the bench slopes at an angle of approximately 18 degrees off vertical. Many rotary rig masts have pinning capabilities permitting drilling at angles as much as 30 degrees out of the vertical. However, the inclined hole drilling capabilities in rotary drilling are limited by the heavy feed force required, since part of this force is directed backwards. This causes rig stability problems, reduced penetration, and shorter life of drilling consumables. Consequently, most blast hole drilling using rotary drillrigs is for vertical holes.

Percussive Drilling Percussive drilling breaks the rock by hammering impacts transferred from the rock drill to the drillbit at the hole bottom. The energy required to break the rock is generated by a pneumatic or hydraulic rock drill. A pressure is built up, which, when released, drives the piston forwards. Figure 1 

Talking Technically

illustrates the principle of top hammer percussive drilling. The piston strikes on the shank adapter, and the kinetic energy of the piston is converted into a stress wave travelling through the drillstring to the hole bottom. In order to obtain the best drilling economy, the entire system, rock drill to drillsteel to rock, must harmonize.

Stress Wave Theoretically, the stress wave has a rectangular shape, the length of which is twice that of the piston, while the height depends on the speed of the piston at the moment of impact, and on the relationship between the crosssectional area of the piston and that of the drillsteel. s 5200 m/s

+ –

2 x piston length

Figure 2 Stress wave energy.

The total energy that the wave c­ ontains is indicated diagramatically in Figure 2. To calculate the output power obtained from a rock drill, the wave energy is multiplied by the impact frequency of the piston, and is usually stated in kW. Rock drill designers seek to find the best com­ binations of various parameters, such as the piston geometry, the impact rate and the frequency. Two rock drills having the same nominal power rating

Efficiency and Losses

s + –

Figure 4 Shock wave generated by pneumatic rock drill.

might therefore have quite different properties. The shock waves that are generated by hydraulic (Figure 3) and pneumatic (Figure 4) rock drills are significantly different in shape. Drillrods used with hydraulic rock drills will normally show substantially longer service life, compared with pneumatic rock drills, because of the higher stress level obtained with the pneumatic driven piston. The reason is the larger cross­section needed when operating at ­substantially lower pressure, which is 6-8 bars, com­pared to the 150-250 bars used with hydraulic systems. The slimmer the piston shape, the lower the stress level. Figure 5 compares the stress level generated by three different pistons having the same weight, but with different shapes and working different pressures. The lowest stress, or shock wave amplitude, is obtained with the long slender piston working at high pressure. Figure 5 Stress level generated by different pistons of same weight. Piston Piston11 – 0,8 MPa

– 8 bar

Piston2 2– –12120 Piston MPabar

Piston MPabar Piston3 3– –20200

Figure 3 Shock wave generated by hydraulic rock drill. s + –

3 2 1 Shock-wave amplitude



The shock wave loses some 6-10% of its energy for every additional coupling, as it travels along the drillstring. This loss is partly due to the difference in cross-sectional area between the rod and the sleeve, and partly due to imperfect contact between the rod faces. The poorer the contact, the greater the energy loss. When the shock wave reaches the bit, it is forced against the rock, thereby crushing it. The efficiency at the bit never reaches 100%, because some of the energy is reflected as a tensile pulse. The poorer the contact between the bit and the rock, the poorer the efficiency (Figure 6). s

Reflecting wave

+ –

Primary wave

Figure 6 Poor contact between bit and rock results in poor efficiency.

To optimize drilling economy, the drilling parameters for percussion ­pressure, feed force, and rotation must harmonize.

Percussion Pressure The higher the percussion pressure, the higher will be the speed of the piston, and consequently, the energy. Where the bit is in good contact with hard and competent rock, the shock wave energy can be utilized to its maximum. Conversely, when the bit has poor contact, the energy cannot leave the drillstring, and reverses up the drillstring as a tensile wave. It is only when drilling in sufficiently hard rock that the maximum energy per blow can be utilized. In soft rock, to reduce the reflected energy, the percussion pressure, and thus the energy, will have to be ­lowered (Figure 7). For any given percussion pressure, the amplitude, and hence the stress in the drillsteel, will be higher with reduced cross-section of the drillrods. Drilling in open pit mining

Talking Technically

Percussion pressure Percussion pressure

Drilling method hole diameter, mm

Soft rock

Hard rock

Figure 7 To reduce reflected energy, percussion pressure is lowered.

To get the longest possible service life from shank adapters and rods, it is important to ensure that the working pressure is matched to the drillstring at all times.

Feed Force The purpose of the feed is to maintain the drillbit in close contact against the rock. However, the bit must still be able to rotate. The feed force must always be matched to the percussion pressure. Figure 8 illustrates this ­relationship.

Rotation The purpose of rotation is to turn the drillbit to a suitable new position for the next blow. Using button bits, the periphery is turned about 10 mm between blows. Consequently, the rotation rate is increased using higher impact frequency and reduced bit diameter. Using insert bits, the ­recom­mended rotation rate is 25% higher.

Setting Parameters In practice, the driller sets the percussion pressure that the rock can cope Figure 8 Feed force must be matched to percussion pressure. Feeding

Low percussion pressure

High percussion pressure

Drilling in open pit mining

Hydraulic Tophammer

DTH

COPROD

76-127

85-165

105-165

penetration rate

2

1

3

hole straightness

1

3

3

hole depth

1

3

3

production capacity (tons rock/shift)

2

1

3

fuel consumption/drill metre

2

1

2

service life of drillstring

1

2

3

investment in drillstring

2

2

1

suitability for good drilling conditions

3

2

2

suitability for difficult drilling conditions

1

3

3

simplicity for operator

2

3

1

adjustability of flushing capacity

1

2

3

Figure 9: Comparison for 20 m bench drilling in a limestone quarry. Ratings: fair = 1, good = 2, very good = 3.

with, and then sets the rev/min with regard to the percussive frequency and the bit diameter. When drilling starts, the feed is adjusted to get even and smooth rotation. In case this is not achieved, which will show up in low shank adapter life, the percussion pressure can be progressively reduced, until even and smooth rotation is reached. The temperature of the adapter sleeve can be checked to ensure that the drilling parameters are correctly set. Immediately after drilling, the temperature should be 60-70 degrees for dry drilling, and approximately 40 degrees for wet drilling. Drilling problems, mainly related to loose couplings, may arise whatever parameters are used. In order to tighten the couplings during drilling, the ­ friction of the bit against the hole bottom has to be increased. This can be done by increasing the feed, increasing the rotation rate, or changing the bit.

Flushing Drill cuttings are removed from the hole bottom to the surface by air blowing or water flushing. As the power output from rock drills in­creases, accompanied by increased penetration rate, efficient flushing becomes gradually more important. The flushing medium is normally air for

surface drilling, and water for underground drilling. The required flushing speed will depend on:    specific gravity– material having a density of 2 t/cu m requires at least 10 m/sec, whereas iron ore, for example, having a density of 4 t/cu m, requires an air speed of 25-30 m/sec;    particle size – the larger the particles, the higher flushing speed required;    particle shape – spherical particles require more speed than flaky, leaf shaped particles.

Productivity and Methodology During the past century there has been a rapid and impressive increase in efficiency and productivity related to tophammer drilling. Starting from hitting a steel manually by a sledge hammer 100 years ago, today’s hydraulically powered rock drills ­ utilize the latest state-of-the-art ­technology. Every drilling method has its pros and cons, making an objective comparison quite cumbersome. In view of this, the table in Figure 9 can serve as a guideline when comparing the ­various percussion drilling alternatives which Atlas Copco can offer. The choice of best drilling method to apply depends on hole size and type of application.

by Hans Fernberg 

Talking Technically

Principles of Rock Blasting Combination of Factors Blasting by design results from a large number of factors, all of which need to be brought under control in order to achieve the right result. These include the choice of drillrig and tools, the layout of the holes, the explosive, and the skill of the operators. Geology is the governing factor, and experience is a major ingredient. Atlas Copco produces drillrigs and systems to suit all rock types, and has the experience to recommend the correct approach to all ground conditions in order to achieve the ­optimum result. The following outline of the principles involved in rock blasting is a logical start point in the quest for the ­perfect round.

Blasting To understand the principles of rock blasting, it is necessary to start with the rock fragmentation process that follows the detonation of the explosives in a drillhole. The explosion is a very rapid ­combustion, in which the energy contained in the explosives is released in the form of heat and gas pressure. The transformation acts on the rock in three consecutive stages (figures 1-3). Compression: a pressure wave propagates through the rock at a velocity of 2,500-6,000 m/sec, depending on rock type and type of explosives. This pressure wave creates microfractures which promote rock fracturing. Reflection: during the next stage, the pressure wave bounces back from the free surface, which is normally the bench wall or natural fissures in the rock. The compression wave is now transformed into tension and shear waves, increasing the fracturing process. Gas Pressure: large volumes of gas are released, entering and expanding the cracks under high pressure. Where the distance between the blasthole and 10

Compression

Reflection

Gas Pressure

Figures 1-3 Rock breaking sequence in a normal blast.

the free face has been correctly calculated, the rock mass will yield and be thrown forward.

Benching Bench blasting is normally carried out by blasting a large number of parallel holes in each round. Considering the blasting mechanics, with a compression-reflection-gas pressure stage in consecutive order for each charge, it is of vital importance to have a proper delay between each row, and even between individual holes in each row. A proper delay will reduce rock throw, improve fragmentation, and limit ground vibrations. The blast should be planned so that the rock from the first row of holes has moved about one third of the burden, when the next row is blasted (figures 4 and 5). The horizontal distance between the

hole and the free face is the burden, and the parallel distance between holes in a row is the spacing. The ratio between spacing and burden will have great impact on the blasting result, and 1.25 can be considered as an average ratio. The optimum burden depends upon a number of parameters, such as rock type, required fragmentation, type of explosives, hole deviation, and hole inclination. Nevertheless, as large drillholes can accommodate more explosives, there is a distinct relationship between burden and hole dia­meter (figure 6). As the bottom part of the blast is the constricted and critical part for successful blasting, it is used as a basis for deciding all other parameters. The bottom charge, normally 1.5 x burden, from where the initiation should start, requires well-packed explosives of higher blasting power than is needed in the column charge (figure 7).

Figure 4 Delay detonation of a typical bench blast.

Drilling in open pit mining

Talking Technically

base type detonation velocity m/s features nitro-glycerine dynamite 5500-4500 highly adaptable cartridged gelatin excellent in smaller holes

Firing pattern

This firing pattern provides separate delay time for practically all blastholes and gives good fragmentation as well as good breakage in the bottom part of the round.

ammoniumnitrate

ANFO

2500

low cost, high safety, easy to pour or blow no water resistance, contains 5-6% fuel oil

water

slurry

4000-3000 watergel

basically ANFO made water resistant gel stable oil/water emulsion – heavy ANFO packaged or pumpable

5000 emulsion range depends on storage time

Figure 5 Firing sequence in delay blasting.

Table 1 Features of common types of explosives.

Stemming of the top part of the hole is used to ensure that the energy of explosives is properly utilized. It will also reduce and control the fly rock ejected from the blast. This tends to travel long distances, and is the main cause of on-site fatalities and damage to equipment. Dry sand or gravel having a particle size of 4 to 9 mm constitutes the ideal stemming material. Inclined holes give less back break, safer benches and less boulders, when compared to vertical holes.

Types of Explosives The geology frequently has more effect on the fragmentation than does the explosive used in the blast. The properties that influence the result of the blast are compressive strength, tensile strength, density, propagation velocity, hardness and structureIn general, rock has a tensile strength which is 8 to 10 times lower than the compressive strength. Figure 6 Burden as a function of drill hole diameter.

The tensile strength has to be exceeded during the blast, otherwise the rock will not break. High rock density requires more explosives to achieve the ­displacement. The propagation velocity varies with different kinds of rock, and is reduced by cracks and fault zones. Hard, homogeneous rocks, with high propagation velocity, are best fragmented by an explosive having high velocity of detonation (VOD). An extensive range of different types and grades of explosives is available to suit various blasting applications. A breakdown is presented in Table 1. In dry conditions, ANFO has become the most used blasting agent, due to its availability and economy. The blasthole diameter, together with the type of explosive used, will determine burden and hole depth. Practical

hole diameters for bench drilling range from 30 to 400 mm. Generally, the cost of large diameter drilling and blasting is cheaper per cubic metre than using small holes. However, rock fragmentation is better controlled by higher specific drilling. The explosives are initiated with ­detonators which can be electric or non-electric. Electric systems have the advantage that the complete circuit can easily be checked with an ohmmeter to ensure that all connections and detonators are correct before blasting. To eliminate the risk for spontaneous ignition from lightning, non-electric systems, including ­ detonating cord, are used.

by Hans Fernberg

Figure 7 Charging for optimum fragmentation. Boulders and flyrock come from this zone

Burden as a function of Drill Hole Diameter Practical Values

Stemming (length ~ burden)

Back break Burden

Column charge only light charge needed for good fragmentation

Hole Diameter, mm Spacing Equal to 1.25 x Burden

Drilling in open pit mining

Bottom charge requires well packed high blasting power

Subdrilling = 0.3 x burden

11

Talking Technically

Putting Rotary Drilling into Perspective Rotary or DTH Atlas Copco now offers a complete range of rotary as well as DTH and tophammer drill rigs for most types of open pit mining and quarrying applications. But how do these technologies complement each other and how do drillers know which method to choose, and when? As readers of M&C are well acquainted with DTH drilling, this article puts rotary drilling into perspective.

Fig 1. Drilling methods (1) Down-the-Hole (DTH); (2) Tophammer; (3) COPROD; (4) Rotary tricone.

TONS

Complete Range With the acquisition of the IngersollRand’s Drilling Solutions and Baker Hughes Mining Tools (BHMT) businesses, there is now another way to break rock within the Atlas Copco family of products. Much of the world’s mining output begins through drilling of holes with rotary drills. IngersollRand built air-powered rotary drills for many years prior to the introduction of their first fully hydraulic unit, the T4, in 1968.

About Rotary Drills It is important to note that rotary drills are capable of two methods of drilling. The majority of the units operate By Brian Fox, Vice President Marketing, Atlas Copco Drilling Solutions, USA.

12

as pure rotary drills, driving tricone or fixed-type bits. The fixed-type bits, such as claw or drag bits, have no moving parts and cut through rock by shearing it. Thus, these bits are limited to the softest material. The other method utilized by rotary drill rigs is down-the-hole (DTH) drilling. High pressure air compressors are used to provide compressed air through the drill string to drive the DTH hammer.   The main blasthole drilling methods are shown in Fig 1. The primary difference between rotary drilling and other methods is the absence of percussion. In most rotary applications, the preferred bit is the tricone bit. Tricone bits rely on crushing and spalling the rock. This is accomplished through transferring down-force, known as pulldown, to the bit while rotating in order to drive the carbides into the rock as the three cones rotate around their respective axis. Rotation is provided by a hydraulic or electric motor-driven gearbox (called a rotary head) that moves up and down the tower via a feed system. Feed systems utilize cables,

chains or rack-and-pinion mechanisms driven by hydraulic cylinders, hydraulic motors or electric motors. Pulldown is the force generated by the feed system. The actual weight on bit, or bit load, is the pulldown plus any dead weight such as the rotary head, drill rods and cables.

More Weight with Rotary It only takes one look to see that the biggest DTH and tophammer drill rigs are very different to the biggest rotary blasthole rigs. In fact, the Pit Viper 351 rotary drill rig weighs in excess of nine times that of our largest DTH hammer drill rig, the ROC L8. Yet it is drilling a hole that is generally only twice the diameter. Take a typical medium formation tricone bit with a recommended maximum loading of 900 kg/ cm of bit diameter (5000 lbs per inch of diameter). With a 200 mm (7-7/8”) bit, you could run about 18,000 kg (40,000 lbs) of weight on the bit. The laws of physics dictate that for every action, there is an equal and opposite Drilling in Open Pit Mining

Talking Technically

Fig 2: The Atlas Copco product range by application and method.

Surface Drilling Applications Construction

Aggregate Industrial Minerals Gold Coal

Copper Iron

Hole Diameter 2" 51mm

3" 76mm

4" 102mm

5" 127mm

6" 152mm

7" 178mm

8" 203mm

9" 229mm

10" 254mm

11" 279mm

12" 305mm

PV-351 DM-H2 90,000 LB DM-M3 PV-271/PV-275 DM-M2

13" 330mm

14" 356mm

15" 381mm

16" 406mm

125,000 LB Bit Load 110,000 LB

75,000 LB 75,000 LB 50,000 LB 60,000 LB 45,000LB 30,000 LB 30,000 LB

DMLSP DML DM45 T4BH

DTH

25,000 LB

Tophammer/COPROD

With the acquisition of the IngersollRand’s Drilling Solutions and Baker Hughes Mining Tools (BHMT) businesses, there is now another way to break rock within the Atlas Copco family of products. Much of the world’s mining output begins through drilling of holes with rotary drills. IngersollRand built air-powered rotary drills for many years prior to the introduction of their first fully hydraulic unit, the T4, in 1968.

methods is the absence of percussion. In most rotary applications, the preferred bit is the tricone bit. Tricone bits rely on crushing and spalling the rock. This is accomplished through transferring down-force, known as pulldown, to the bit while rotating in order to drive the carbides into the rock as the three cones rotate around their respective axis. Rotation is provided by a hydraulic or electric motor-driven gearbox (called a rotary head) that moves up and down the tower via a feed system. Feed systems utilize cables, chains or rack-and-pinion mechanisms driven by hydraulic cylinders, hydraulic motors or electric motors. Pulldown is the force generated by the feed system. The actual weight on bit, or bit load, is the pulldown plus any dead weight such as the rotary head, drill rods and cables.

About Rotary Drills

More Weight with Rotary

It is important to note that rotary drills are capable of two methods of drilling. The majority of the units operate as pure rotary drills, driving tricone or fixed-type bits. The fixed-type bits, such as claw or drag bits, have no moving parts and cut through rock by shearing it. Thus, these bits are limited to the softest material. The other method utilized by rotary drill rigs is down-the-hole (DTH) drilling. High pressure air compressors are used to provide compressed air through the drill string to drive the DTH hammer.   The main blasthole drilling methods are shown in Fig 1. The primary difference between rotary drilling and other

It only takes one look to see that the biggest DTH and tophammer drill rigs are very different to the biggest rotary blasthole rigs. In fact, the Pit Viper 351 rotary drill rig weighs in excess of nine times that of our largest DTH hammer drill rig, the ROC L8. Yet it is drilling a hole that is generally only twice the diameter. Take a typical medium formation tricone bit with a recommended maximum loading of 900 kg/ cm of bit diameter (5000 lbs per inch of diameter). With a 200 mm (7-7/8”) bit, you could run about 18,000 kg (40,000 lbs) of weight on the bit. The laws of physics dictate that for every action, there is an equal and opposite

Complete Range

Drilling in Open Pit Mining

Rotary Rotary or DTH

DM30

DM25SP ROC L8 CM780D CM760D ROC L6 ROC L7/L7CR ECM720 ROC F9 ROC F6 ECM660III ROC F7 ROC D3/D5/D7 ECM585MC ECM470

KEY:

reaction, meaning that if you push on the ground with 18,000 kg (40,000 lbs), the same force will push back on the unit. Therefore, the weight of the machine must be over 18,000 kg (40,000 lbs) at the location of the drill string to avoid the machine “lifting off” the jacks. To achieve a stable platform through proper placement of the tracks and levelling jacks, the distribution of weight results in an overall machine weight that approaches or exceeds twice the bit load rating. This weight does add cost to the machine, but the size of the components also translates to long life. Even smaller rotary blasthole drills are built to run 30,000 hours of operation.

The Importance of Air A key parameter of rotary drilling is flushing the cuttings from the hole. In most rotary blasthole drills, cuttings are lifted between the wall of the hole and the drill rods by compressed air. Sufficient air volume is required to lift these cuttings.   Many types of tricone bits have been developed to meet various drilling needs. Softer formation bits are built with long carbides with wide spacing on the face of the bit. This design yields large cuttings which increase drill speed and reduce dust. It is important to have sufficient clearance between the wall of the hole and the drill rods in order for such large cuttings to pass. If this clearance, known as annular area, is not sufficient, the cuttings will be ground between the wall of the hole and the rods or by the bit itself 13

Talking Technically

Studies have shown that pure penetration rate will increase linearly with increased pulldown. The same has also been said of rotation speed. So why doesn’t every operation use more of each? Unfortunately, higher pulldown and rpm usually results in increased vibration and lower bit life. The vibration causes increased wear-and-tear on the rig, but more importantly, it creates a very unpleasant environment for the operator. What invariably happens is that the operator reduces the weight or rpm until the vibration returns to a comfortable level. Some operations limit bit load and rpm even if there is 14

Production Rate (Feet/Hour) Bit Life (Feet) Bit Cost Bit Cost/Foot Rig Cost/Hour Total Drilling Cost/Foot

Steady Eddie

Smart Sam

Wild Jack

120 10,000 $4,000 $0.40 $175 $1.86

138 8,000 $4,000 $0.50 $175 $1.77

180 4,000 $4,000 $1.00 $175 $1.97

Fig 3. The table compares three operators on the same drill rig – Steady Eddie, Smart Sam and Wild Jack. The cost chart, using actual data collected at a major copper mine further­ illustrates the balance required.

no vibration in order to improve bit life. This is often the wrong strategy as the overall drilling cost per unit, also known as Total Drilling Cost (TDC), should be considered.   TDC is calculated using the bit cost per metre/foot and the total rig cost per hour. The unit cost per hour includes labour, maintenance and power, and possibly the capital cost. The drilling speed really doesn’t impact this cost per hour figure. What it does impact though is the cost per unit produced (cost/metre/foot, cost/ton, etc…). You generally want to push the rig harder to reduce the cost/foot, but there will be a point where the rig overloads the bits (see fig's 3 and 4).

Large versus Small There are some drawbacks to rotary rigs. Smaller crawler rigs are more flexible with many advantages such as articulating and extendable booms and guides that allow drilling at many different angles. Some models also offer

significantly more technology with automated rod handling systems and automatic drilling. The components on rotary rigs are not enclosed. They are mounted onto the frame in an open layout which makes them extremely easy to service. Looks are not of primary concern for a rig that is subjected to the rigors of breaking rock for more than 60,000 hours.   The general trend for 165 mm (6-1/2”) or less is towards the smaller, more flexible units. However, many large scale quarries and small mines still favour the durability, life and simplicity of the larger rotary rigs for these small diameters. For the large scale open pit operations that yield a high percentage of the total worldwide mineral production, it is anticipated that rotary drilling will remain the primary method for years to come.

Acknowledgements This article first appeared in Mining & Construction No 2, 2005. ■

Fig 4. The impact of bit life and productivity on overall cost/foot (1 ft = 0.305 metres). 14000

12000

$6,00

Footage/24 Hours Bit Life (ft) Overall Cost/Ft

$5,00

10000 $4,00 8000 $3,00 6000

4000

2000

0

299 ft/hour, 1500' bit life High Production

Overall Cost/Foot

Productivity versus Cost

Operator

Footage/24 Hours & Average Bit Life

of air is required. Take for example a Secoroc QL80 203 mm (8”) DTH hammer that is designed to operate at 25 bar (350 psi). Even with our largest high pressure compressor with 686 litres per second (1,450 ft3/min), the pressure will only build to 23 bar (325 psi), thus providing less impact energy. In real terms, each blow of the piston is about 45 kg (100 lbs) less than it is designed for. In some cases, this method will still out-perform rotary drilling. For most large diameter blasthole drilling, there is simply not enough air on-board for a DTH to be as cost effective as rotary drilling with a tricone bit.   Rotary drilling is still the predominant method of drilling 230 mm (9”) diameter or greater. This is driven primarily by the current limitations of tophammer units and rig air systems. Tricone bits also become more cost effective as the larger bits are equipped with larger bearings which in turn can handle higher loads. These higher loads translate to improved drill rates.   Another advantage of rotary rigs is the length of the drill rods that can be carried on board. Longer rods mean fewer connections. Further, some rotary rigs are large enough to handle a long tower that enables drilling of the entire bench height in a single-pass. At the largest open pit mines, rotary units are drilling 20 m (65 ft) deep holes in a single-pass to match the bench heights dictated by the large electric shovels which can dig a 17 m (55 ft) bench.

$2,00 218 ft/hour, 5300' bit life Lowest Cost

74 ft/hour, 12,000' bit life Great Bit Life

$1,00

$-

Drilling in Open Pit Mining

Talking Technically

SmartRig Takes Control hcS to Plc to Pc Acronyms are plentiful when it comes to automation, but PC-based will be the most important acronym in the years to come. Ever since Atlas Copco developed Hydraulic Control System (HCS) in the 1970s, the search has been on for its successor. Programmable Logic Control (PLC) saw us through the 1990s along with the VME-system, but in 2002 the first SmartRigs started to take over. SmartRig is a PC-based control system intended for all kinds of automation in simple and advanced drill rigs. The hardware is designed to operate in every possible weather condition, and the software can be upgraded at site. SmartRig has builtin logging and monitoring functions, together with support for diagnostics and faultfinding. The control system is used in all Atlas Copco product families, in both underground and surface crawlers, making it easy to move functions and improvements between different products. That’s smart!

control System Via PC software, the SmartRig control system generates electrical signals to control the hydraulic valves. This introduces the concept of a “dry cab”, with no hydraulic pipework and gauges, considerably reducing noise for the operator. The number of hydraulic components has been reduced by 30%, compared with Hydraulic Control System, HCS, resulting in higher efficiency. The need for electrical cables is also reduced. Control gauges and instruments are replaced by a display unit. This releases space in the cab, increasing visibility, and improving operator ergonomics. The fundamentals of the rock drill control system are RPCF control and anti-jamming functions. RPCF, or Rotation Pressure Control of Feed pressure, adjusts the feed pressure according to the measured feed pressure. This keeps the joints correctly tightened and Drilling in open pit mining

• Hole Navigation System (HNS) • Measure While Drilling (MWD) • Automatic rod adding (AutoRAS) • Automatic feed inclination setup (AutoPOS) • Laser Plane • Advanced Drilling System • Silenced • ROC Manager

Atlas Copco´s Silenced ROC D7C is a sound investment with a noise level of approximately 10 dB(A) below that of other rigs on the market.

saves drill steel. Anti-jamming uses the rotation pressure to detect a jamming situation, and will reverse the feed of the rock drill and initiate a replacement hole collaring. Together, this advanced system of drilling control will give maximum life to the entire drill string, while ensuring high penetration rates and easy rod extraction.

automation in Surface Drilling Using the laser plane as a reference level, all holes are drilled to the same depth, reducing drilling, blasting and crushing costs by way of better fragmentation, and cancelling the need for secondary blasting. A flatter, more uniform bench surface results, making loading and transportation easier. Automatic feed positioning reduces set-up time and cancels out operator error. More parallel holes result in better blasting and smoother bench bottoms. The longer the hole, the bigger will be the impact of even a small deviation on blasting. For instance, a one degree error will

produce a deviation of 36 cm at the bottom of a 20 m hole. Hence the importance of automatic feed positioning, which sets the feed to pre-defined angles at the touch of a button. The automatic rod adding system, AutoRAS, enables the operator to drill a hole automatically to a given depth, allowing him to leave the cab to carry out other duties, such as maintenance checks or grinding bits, while keeping the drill rig in sight. The drilling is supervised by the drillsteel break detection system, which shuts down the drilling operation if a breakage is detected. The result is better rig utilization, evidenced by a couple of extra holes/shift.

MWD and ROc Manager Measure While Drilling, or MWD, is an optional instrumentation and software package for recording and interpretation of drilling data, and enhanced presentation of geomechanical variation of rock properties. A number of parameters, such as hole depth, penetration rate, and damper, feed, percussion and rotation pressures are logged at requested 15

Talking Technically

1400 m 1200 1000 600

800

400 200

Silenced for Noise Sensitive Areas

200 400 600 800 1000 1200 1400 m

55dB (A) area

With Silencing Kit

Without Silencing Kit

The noise carpet shows the difference with and without a Silencing Kit.

intervals while drilling, and this provides input to analysis of the rock properties. Date, time, hole length, feed angle, and rig identity are logged once for each hole. MWD data can be recorded for every second centimetre up to a maximum penetration rate of 3 m/min. In this way, data is extracted from every production hole to provide very highresolution rock mass characterization. Typical parameters being reported are rock hardness and fracturing. Detailed information on rock mass properties is available immediately after drilling is completed, without disturbing production, since logging is carried out automatically during the normal drilling process. ROC Manager is a stand-alone PCbased tool for making drill plans, measuring hole deviation, and logging, presenting and reporting drilling data graphically. This information can be presented individually or in combination with other parameters, and used both during drilling operations, and by transferring logged data from the rig. Advanced MWD analysis is also possible as an option. Both the SmartRig and ROC Manager 2.0 support the IREDES format for data exchange on performance, 16

the computer will provide the information to place and align the feed exactly over the collaring position. The drillplan can be provided by ROC Manager, transferred to the rig via a PC card. The time saved by not having to aim visually to set angles, and by being able to drill more than one hole from a single set-up, results in better rig utilization.

quality and MWD logs, and on drill plans. In ROC Manager, the MWD data can be illustrated in slices through the bench, with the rock properties identified by contrasting colours, providing a map of the mineral qualities and types. This facility differentiates between good rock and poor rock, for instance, allowing the quarry or mine operator to select rock for excavation, and to prepare for loading and hauling before blasting takes place.

Hole Navigation System Real-time satellite-based Global Positioning System, HNS, has been chosen for the highest possible drillrig navigation accuracy, within 10 cm in most situations. With HNS there is no need to mark out holes, and the accuracy is such that all holes will be parallel, if required, resulting in a controllable product with better fragmentation and less boulders. The focus is on road construction applications, but the system can be used in any type of drilling. Using information on his display, the operator can navigate the rig to the coverage position for a given hole, and

The sources and characteristics of noise are complicated, and have to be identified and analysed in order to analyze their spectrum. Atlas Copco designed a concept rig in 2000, and a second prototype rig in 2004, both of which were used as testbeds for various simulations. These confirmed that noise was not just created by the drilling cycle, but also by elements of the carrier, such as cooling fans, hydraulic system components, and engine. The recently introduced Silenced SmartRig is for use in areas where noise levels have to be controlled. Substantial efforts have been put into redesigning components, systems and soundproofing enclosures, resulting in a 10dB(A) external noise reduction. The most visible difference between the Silenced SmartRig and other Smart Rig rigs is its patented feed enclosure. The frame and panels of the enclosure are formed from lightweight aluminium. There are four access doors, which are hydraulically operated from the cab. A rubber sliding skirt at its base encloses the hole, and this can be hydraulically raised for collaring. The whole enclosure is designed for demounting when not needed. The SmartRig system, because it delivers the right amount of power for each phase of the drilling operation, can reduce fuel consumption by up to 30%. Add this to the productivity increase from automatic rod adding and auto feed alignment, and the Silenced Smart Rig is a really sound investment!

by Jean Lindroos

Drilling in open pit mining

Talking Technically

Correct Selection of Tophammer Rock Drilling Tools Optimizing Penetration Rates In order to achieve best possible penetration rate, a bit should be chosen where the total contact area between the cemented carbide and the rock creates the best possible penetration per blow. As a rule of thumb, the ­following penetration rate index can be used: button bit with ballistic buttons, 130; button bit with spherical buttons, 115; insert bit, 100. However, when bits are compared for hole straightness, a different order emerges, with the insert bit on top, followed by the button bit with ballistic buttons, and lastly, the button bit with spherical ­buttons. This article is intended to guide the driller through the range of bits, rods and shank adapters to assist with the best choice of rock tools for the particular job.

Criteria of Choice Since button bits are used for 99% of surface drilling applications, a bit with guiding wings on the bit skirt, the Retrac-type bit, should be chosen to give the straightest possible hole. The bit front should not be allowed to take on a convex shape during service life, since this convex front has been shown to give more deflection than a flat or drop centre front. When a button bit is worn, it is the gauge buttons that always show the most wear. This means that the gauge buttons lose more height during regrinding, leading to the tendency for the bit front to become convex. A drop centre bit, thanks to its lowered centre, will not become convex during the bit life, and is thus the best choice, wherever possible. If the above criteria are taken into account, the choice of bit, in descending order, should be: Retrac button bit with ballistic buttons and drop centre Drilling in open pit mining

front; Retrac button bit with spherical button and drop centre front; Retrac button bit with spherical buttons and flat front; Insert bit, only used when very straight holes are required and nothing else works.

Duty bits, Model –20 or –21, where the gauge buttons are larger than the front buttons. Extra Heavy Duty Model –21 has better flushing characteristics, due to different clearance angle and shorter head. Recommended in extremely hard and abrasive rock.

Bit Designs Flat Front, Standard The standard bit is most suitable for medium-hard to hard rock, where it gives good ­ performance and long service life in normal conditions. Standard bits are easy to regrind, as the front and gauge buttons usually are the same size. Flat Front, Heavy Duty Hard rock, containing quartz and pyrites, often causes considerable wear to the gauge buttons. When drilling in rock with this characteristic, it is common practice to use Heavy

Drop Centre Excellent results are obtained with the Drop Centre bit in soft to medium hard rock, with high penetration potential. The Drop Centre bit has outstanding flushing characteristics, and the cuttings are distributed evenly around the steel body, so minimizing steel wash. The drop centre part of the bit front produces a rock elevation or bump during drilling, which gives good guidance to the bit.

Bit designs and rock types

DC = Drop Centre; FF = Flat Front; HD = Heavy Duty; XHD = Extra Heavy Duty. 17

Talking Technically

and are preferred where there is a tendency for squaring of the hole.

Drop Centre Extra Heavy Duty Gauge buttons are larger than the front buttons, there are no side ­flushing holes, and the head is shorter. Re­commended in extremely hard and abrasive rock, but can also be used in medium hard rock.

Retrac Skirt The Retrac bit has cutting edges at the rear of the bit, allowing it to “drill” in reverse. This is an important feature when drilling in loose, broken or fissured rock, where it can be difficult to retract the drillstring due to hole collapse. In addition, the Retrac bit has deep grooves milled along the bit body for efficient cutting removal. The good guidance of this bit gives straighter holes.

Insert Bits These are very seldom used, except when very straight holes are required. Cross bits normally have cemented carbide inserts with a carbide grade for high wear resistance. X-bits normally have a carbide grade for im­proved toughness, 18

Drillrod Selection For bench drilling, three types of drillrods can be chosen: surface hardened rods, in which only the thread parts are hardened; carburized rods, where all surfaces, including the inside of the flushing hole, are hardened; and carburized Speedrods, having integrated couplings with male and female threads at opposite ends. Surface Hardened Rods Surface hardened rods are the toughest, and can take more abuse than the carburized rods, but they have the lowest fatigue strength. They are a good choice when drilling in faulted or folded formations, when driller abuse, or lack of care and maintenance, are factors. Tiger Rods The new M-F Tiger Rods from Atlas Copco Secoroc are specially developed for surface drilling applications. They are composed of selected steels to give increased service life and better performance. The female thread is fully carburized, while the rest of the rod is surface hardened. The new Tiger Rods are friction-welded, so that the best steel grade can be selected for each section. This improved production technology reduces the risks of pitting on the threads, and rod and thread end breakage, while tighter thread tolerance improves the total service life of the whole drill string. Rigorous tests in various locations have shown that Tiger Rod is a drill string without any weak parts. Carburized Rods A carburized rod has better wear resistance and a higher fatigue life compared to surface hardened rods. Demands good treatment, and hole deflection should be limited by putting guiding equipment in the string, at least when drilling holes deeper than 10 m. Their life will be 20%-30% longer if they are handled correctly, and guiding equipment is used when necessary. When lighter drillrods are required for manual rod handling, the carburized hexagonal rod is ­recommended.

When drilling with a number of rods in a string, using standard rods and couplings, the loss of energy in every joint is about 6%, if the connection is tight. If drilling with open threads, the energy loss at each joint can easily climb to 10%. Therefore, it is advantageous to use the maximum rod length possible. Speedrods If Speedrod carburized rods with integrated coupling are used, the energy loss per joint is less, since the mass (weight) of the joint is less than that of standard coupling joints. The energy loss is about 3.5%, which is 60% of that of standard joints. In practice, the energy advantage of Speedrod joints compared to standard couplings is even greater, since it is easier to keep the Speedrod joint tight during drilling. Field tests have shown that, when drilling 20 m holes with 4 m rods, the penetration increase is about 15% when using Speedrods. The faster penetration and easier handling increase productivity, and due to better energy transmission, the joints are easily ­loosened. From the point of view of drilling straight holes, rods that are as rigid as possible for the drilled hole diameter are best. For straight hole drilling, a Guide Rod or Guide Tube should be used as the first rod after the bit, to give the drillstring guidance. Further information about rods is available in the yellow technical specification pages in this reference edition. Shank Adapters The task of the shank adapter is to transmit rotation torque, feed force, impact energy, and flushing medium. It is made from specially selected material to withstand the transmission of impact energy and rotation from the rock drill to the drillstring, and is hardened through carburizing. Around 400 different shank adapters are currently available from Atlas Copco Secoroc. Shank adapters can be divided into three main types, based on the technique used to transfer the rotation motor torque to the drillrod.

by Alf Stenqvist Drilling in open pit mining

Talking Technically

Full-ballistic button bits for soft rock Atlas Copco Secoroc has extended the range of button bits for surface drilling with two new models for drilling in soft rock formations. The new models are designated –21­–66 and –47–66. The designation –66 means that all the buttons are ­full-ballistic in shape and protrude 20–25% more than standard ballistic buttons. Model –21 has larger gauge buttons whereas all the buttons are the same size on model –47 . The longer button protrusion helps the bit to penetrate deeper into the rock with each hammer stroke. Both model –21 and model –47 have excellent flushing capacity for the removal of the cuttings from the front of the bit head. The flushing is concentrated to four large flushing holes in the bit front plus equally deep and wide flushing grooves in

Secoroc full-ballistic button bit (dia 76 mm.) model –21–66. Drop centre front with larger gauge buttons.

ThunderRod T60 – for the most powerful tophammer drill rigs

Secoroc full-ballistic button bit (dia 127 mm.) model –47–66. Flat front with same size front and gauge buttons.

the front and sides of the bit head. A shorter bit head and larger clearing angle also allow for better flushing of cuttings on models –21 and –47. Increased penetration rate During tests in soft rock in Korea, Malaysia and Australia, these new bits showed much higher penetration rates than standard ballistic button bits, while their service life remained the same. Model –21–66 bits with drop centre front are available with T38 thread in sizes 76 mm (3 in) and 89 mm (3.5 in). Model –47–66 bits with flat front design can be supplied with T45 thread in size 89 mm (3.5 in) and with T51 thread in sizes 102 mm (4 in) and 127 mm (5 in). More sizes and thread combinations will follow.

The full-ballistic buttons protrude more from the bit body, resulting in faster penetration in soft rock.

Drilling in open pit mining

Atlas Copco Secoroc has launched ThunderRod T60, a heavy-duty tophammer drill string designed for greater productivity. Specially designed with a bigger rod crosssection for 102-152 mm holes, ThunderRod T60 is built to handle the most powerful hydraulic rock drills, delivering higher power output for optimization of the drilling pattern. The entire drillstring is more rigid, offering increased hole straightness, higher penetration rate and a welcome boost to drilling productivity and economy. Fewer, but larger, drill holes per blast means higher productivity. Straighter holes result in improved fragmentation and far less secondary drilling and blasting. The threads on ThunderRod T60 are designed to make the coupling sequence as easy as possible, while at the same time keeping energy losses to an absolute minimum. Featuring a cross-section 40% bigger than standard T51 rods, the new ThunderRod is designed to reduce hole deviation in all rock formations. The flushing hole is also bigger, ensuring a 10% increase in flushing capacity for up to 30 m-deep holes. The new shank adapters for ThunderRod T60 are optimally hardened, with a balance of core and surface properties designed to withstand the high impact power of modern rock drills such as Atlas Copco COP 2560, COP 2560EX and COP 4050. This leads to unparalleled fatigue and wear resistance.

19

Talking Technically

COPROD Combines the Best of DTH and Tophammer Drilling The Rock Driller’s Dream Drillers always dreamed of a system that would combine the straightness and accuracy of downthe-hole drilling with the enormous capacity of hydraulic tophammer drilling. Efforts to combine the advantages of the two techniques were unsuccessful, until the development of COPROD by Atlas Copco.   COPROD is not only a combination of positive features, it also integrates two types of drillstring for percussive drilling by means of a tophammer. Inner drillrods transmit power and thrust to the drillbit and outer tubes transfer rotation, adding stiffness to the string and improved flushing efficiency. These assets achieve high tophammer drilling rates and large hole diameters.    The rods in the COPROD system have no threads and are simply stacked one on top of the other. Laterally, they are centred by the guide bushes in the tubes which surround them, and longitudinally, contact between rod ends is maintained by the thrust from the top. Thanks to the unique double recoil damping system of the COP rock drills, the rod ends remain in permanent contact, energy losses are almost nil, and drilling efficiency is maintained from start to finish of the hole.

Rock drill

COPROD section

20 – 40 kW Rotation chuck Anvil

COPROD head

Guide Drill rod Guide

Tube driver

Bit tube

Bit chuck

Drill tube

Drill bit Guide

COPROD drilling head arrangement.

equipment works well for smaller hole diameters in solid rock, but it is not so effective in larger hole diameters, or in deteriorating ground conditions. There are problems in transmitting sufficient energy to the bit, especially in deeper holes, and in obtaining satisfactory flushing. In tophammer drilling, the thrust has to be applied from the top to keep the

bit in contact with the bottom of the hole. This can cause the relatively slender drillstring to bend, steering the bit off its intended alignment. Increasingly powerful hydraulic rock drills send more percussive energy down the drillstring, allowing larger hole diameters in benching. However, due to the microscopic movements between mating parts in the threaded drillstring,

COP1838 CR/2150CR/COP 2550CR and COP 4050CR rock drills.

COP 1838CR/2150CR/COP 2550CR COP 1838CR

Introduction CI AA AB

In the simplest of terms, percussive drilling systems go back to manually hitting a steel rod with a bit at one end and, as recoil makes the rod jump back, rotating it at a small angle between blows to ensure that the hole is round. Most drilling for benching operations has been carried out with tophammers, using extension rods connected by threaded coupling sleeves, and an exchangeable drillbit at the bottom end. This 20

COP 4050CR COP 4050 ME-CR

CI AA AB

Drilling in open pit mining

Talking Technically

ROC F9CR retrofitted with second generation COPROD drilling in Belgium.

energy is lost and heat develops. The energy loss may be considerable by the time the shock wave reaches the bit, and there will be thread wear and reduced life of the drillstring components. The down-the-hole (DTH) system was developed to overcome some of the problems associated with hole straightness suffered by tophammer drills. Rigid guide tubes, with a large outer diameter, were developed to keep the drillstring on a straight course, and improve flushing. With a DTH hammer, a series of tubes offers far greater stiffness, and runs closer to the hole walls,

resulting in considerably less deviation than with a tophammer drillstring.

Power with Rigidity The COPROD system combines the power of the tophammer with the rigidity of the DTH drillstring. COPROD rods move longitudinally within each tube, transmitting the rock drill energy to the bit. Lugs on the rods prevent them from sliding out during handling. During drilling operations, if the bit enters a cavity and drops down in its

The new COPROD drillstring provide longer life and higher penetration rate. New bit tube and bit rod design for improved guidance

CO

PR OD

se

cti

on

CR

CO

PR OD

76 a

nd

he

CR

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New design for improved guidance and air flushing 76 -C

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Stronger tube, 8.8 mm wall thickness

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New rod guide design

New strong T-thread connection between tube and end-piece

Drilling in open pit mining

New steel grade increases bit service life

splines in the bit chuck, the hammer senses it, and percussion is interrupted. Rotation is maintained, however, and percussion restarts automatically when the bit meets resistance again. Flushing air enters the bit via a centre channel, which connects to the cylindrical surface in the bit rod. A small amount of air, containing a little oil, escapes via the splines in the chuck and the bit, and lubricates them. On its way up, the flushing air travels between the smooth outside of the tubes and the hole wall, providing a constant cross section, and ideal conditions for flushing the drilling fines. COPROD offers unique features for drilling holes fast and straight. And the more troublesome the ground becomes, the more the incomparable drilling system comes into its own. Thanks to the unique double recoil damping system of the rock drills developed for use with COPROD, the rod ends remain in permanent contact with each other. Thus, there are near-zero energy losses at rod joints, and drilling efficiency is maintained at virtually the same level from the start to the final depth of the hole.

Latest on COPROD The new COPROD drill string features a wide range of improvements. The thickness of the drill tube has been increased to 8.8 mm with a new, stronger female thread connection to the end piece. This results in increased service life, virtually eliminating tube breakage, and helping to limit in-hole deviation. The end piece of the COPROD section has been made shorter and redesigned with a new male T-thread connection to the drill tube, eliminating thread breakage. The diameter of the CR 76 inner rod has been increased and the end diameter of the CR 89 inner rod matches the anvil to optimize service life and penetration rate. In the COPROD head, the bit rod has been redesigned to eliminate the rod guide. Closer tolerances reduce air passage in the bit spline area to a minimum, preventing shank breakage, while improved airflow reduces plugging of the bit. The drill bit itself is now 21

Talking Technically

made of a new grade of steel with high impact and fatigue strength. The diameter of the 89 mm COPROD tube can be worn down to 80 mm before replacement, and, with low air pressure of only 12 bar, less airflow in the annulus results in up to 50% longer life.

Fractured Rock in Austria Asphalt & Beton GmbH, the quarrying division of Austria-based Strabag, produces 18 million t/y at 57 quarries in 11 countries. An Atlas Copco ROC F7CR forms the backbone of the operation at the company’s 650,000 t/y Jakomini quarry located on an Alpine slope in the Bleiberg region of southern Austria. The operation, which is mainly quarrying fractured metamorphic diabase of 140-150 Mpa hardness, features seven benches, each around 20 m-high. Blasthole depths range from 20 m to 26 m, angled at 80 degrees. Presplit drilling is carried out to maintain slope stability of the benches. The ROC F7CR drills 92 mm-diameter holes, using an impact pressure of 120 bar during collaring, and working pressure of 200 bar. Nett penetration is 1 m/min, and each hole takes around 20-30 minutes to drill. After 10,000 drill metres, the wear on the drill tube was 0.5 mm, and five bits had been consumed. The benches are reached by steep gradients, with inclines of up to 30%, a real test of tractability and stability for any drillrig, but one in which the ROC F7CR excels. The COPROD system of straight hole drilling is ideal in the fractured rock, which is subject to water influx while drilling. It is also very fuel-efficient at 0.7 litre/drillmetre, just half of that expected from DTH rigs. Within a month of delivery in 2005, the ROC F7CR was averaging 25 m/h, and has since achieved consistent monthly performances of over 31 m/h.

Abrasive Rock in Belgium Belgian company DGO M3 is a member of the French EPC Group, and one of the largest drilling contractors in Europe. With an annual production 22

ROC F7CR in the Jakomini quarry.

of up to 115,000 drillmetres from 24 quarry sites around the country, the company is heavily reliant on continuous drill rig availability and production. It has a fleet of Atlas Copco rigs, comprising a new ROC F9CR, a second ROC F9CR retrofitted with the new COPROD system and COP 2150 rock drill, a ROC F7CR, and a ROC L6H DTH rig. The COPROD rigs equipped with 127 mm-diameter bits are used for hole depths up to 30 m, while the ROC L6H can go down to 45 m-deep. A wide variety of rock types and formations is drilled, ranging from medium-to-hard limestone and sandstone to granite, porphyry and grit. With COPROD, the company can drill at any of its operations, giving it the necessary flexibility to obtain very high efficiencies. Using the lower air pressure of 12 bar, the flushing air and cuttings do not destroy the hole collar, and a 20 % higher productivity is obtained compared to the 25 bar DTH rig. Rapid bit changeover times also ensure that regrinding and frequent bit

changes do not cause undue delays. At the sites, every drill pattern and blast is designed with Geolaser profiling of the bench, and hole alignment is checked with the Pulsar system. There are currently ten COPROD drill rigs operating in Belgium, nearly all of which are located in the Frenchspeaking Walloon province. These are served by Atlas Copco distributor SEMAT, based at Spy, near Charleroi. SEMAT carries out any major repairs and overhaul work for DGO, whilst the contractor does its own weekly servicing. DGO reports that, over the last two years using the new COPROD system, it no longer breaks tubes, and has recorded a 50% improvement in service life of the drill string. Every six months, each rig is taken out of operation for one week for a major service, usually coinciding with a period of slack demand. Nearly all COPROD rig owners have increased the diameters of their drill bits due to increased confidence in maintaining correct hole alignment, allowing less holes to be drilled for the same output. Drilling in open pit mining

Talking Technically

to a minimum, by downward excavation from the hill. To reduce the noise, dust and danger associated with truck movements, the rock is fed through gyratory crushers, and transported along a system of shafts and conveyors to a stocking area at the bottom of the hill. There are three 6 m-diameter vertical shafts, and one 900 m-long tunnel and two 1,100 m-long tunnels. The altitude causes the quarry to be shrouded in mist quite often, and it can be damp and cold in the winter, affecting the hours and safety of work. ChienKuo carries out two blasts each day, 28 days a month.

Conclusion Ho Ping quarry is located 1,000 m above sea level.

Limestone in Taiwan Ho Ping limestone quarry, at Hualien in Taiwan, has a fleet of six Atlas Copco ROC F9CR crawler drill rigs equipped with the COPROD system and COP 1838 CR rock drills. In operation since 1981, Ho Ping is owned by Taiwan Cement, and produces 12 million t/y of limestone, making it the largest cement quarry in Taiwan. Located about 1,000 m above sea level, the quarry is one of a number operated by Chien-Kuo Construction Co on behalf of the country's major cement

companies. The company also operates in the People's Republic of China, Vietnam, Indonesia and the Philippines. Four Atlas Copco ROC F9CR rigs joined the production fleet in 2001, and another two units were delivered in 2002. They are proving to be highly productive at 25 drillmetres/h, and eminently suited to the type of rock being mined, which is loose and fractured. They are capable of drilling holes to depths of up to 30 m, and diameters up to 127 mm. Site layout at Ho Ping is designed to keep noise, vibration and visual impact

Statistics prove that the COPROD system, in spite of its higher initial cost, offers improved economy, and is sometimes the only solution worth considering when drilling becomes difficult due to demanding ground conditions. COPROD’s superior penetration rate contributes to a lower cost/m drilled than for DTH. In comparison with tophammer drilling with extension steel, COPROD’s better gross penetration and hole quality provide lower cost/t in difficult rock formations. Summing up, COPROD offers unique features for drilling holes straight and fast, and it comes into its own in troublesome ground. Due to the number of components involved, a COPROD

Idealized section through Ho Ping quarry.

Drilling in open pit mining

23

Talking Technically

Immaculate conveyor tunnel at Hualien.

drill string carries a higher price than comparable extension rod, or DTH, strings. However, because the holes are drilled fast and without deviation, permitting the drilling pattern to be opened up, COPROD leads to lower costs per excavated volume of rock. Time is also saved in retracting the drill string in broken ground, or through blasting debris left on top of the bench. The latest COPROD system improves on these advantages, offering longer drill string life and better availability than ever before.

by Lennart Lundin tonnes x 1000

Strong points of different bench drilling methods Tophammer

• Unbeatable under good drilling conditions • Low fuel consumption • Low investment in drill string

Down The Hole

• Straight holes • Deep holes • Very simple method for the operator

COPROD

• Unbeatable under difficult drilling conditions • Straight holes and high productivity • Good penetration rates

24

Drilling in open pit mining

Talking Technically

Increased Productivity With DTH Drilling

DTH Growing in Popularity The DTH drilling method is grow-­ ing in popularity, with increas-­ es in all application segments, including blasthole, water well, foundation, oil & gas, cooling systems and drilling for heat exchange pumps. DTH competes favourably with rotary drilling in open pit mines, mainly thanks to increased pro-­ ductivity and flexibility. Open pit mining has adopted smaller holes where rotary drilling has either been replaced by DTH, or where DTH has been introduced to create a better finish to the pit wall, as the method is also per-­ fect for pre-­splitting and smooth blasting, which avoids backcracking. DTH drilling offers increased productivity, and is favoured by contractors for production drill-­ ing. In larger quarries, the opti-­ mum hole size is 110-140 mm. With today’s demands for strict hole control for safe blasting in populated areas, DTH drilling is a popular choice among quarry operators.

explosives; deep hole drilling capacity, with constant penetration and no energy losses in joints; and efficient energy transmission, with the piston striking directly on the bit. The COP 34-84 series of hammers was introduced from 1992, and immediately became the benchmark for productivity within DTH drilling. Over the years, the increase in average drilling pressure, from 17 bar to a current market standard of 25 bar, has improved hammer performance, and productivity has increased proportionally to air pressure. The introduction of the Atlas Copco ROC L8 and L6 series of highperformance, high-pressure DTH rigs

Cutaway section of Secoroc COP 64 Gold.

gave another boost to the sales of hammers. The flexibility, productivity and manoeuvr­a­bility of these rigs, when equipped with a COP hammer, makes them the most productive ­combination on the market today.

COP 64 Gold The increase in drilling pressure also had some negative impact on the­ internal components of the DTH hammer, as the increased stress promoted the New Secoroc hammer and bit ready for action on an Atlas Copco drill rig.

Quality Holes In the hole range 100-254 mm, DTH drilling is the dominant drilling method today. The main features of DTH drilling in this hole range are: excellent hole straightness within 1.5% deviation without guiding equipment; good hole cleaning, with plenty of air for hole cleaning from the hammer; good hole quality, with smooth and even hole walls for easy charging of Drilling in open pit mining

25

Talking Technically

risk of premature failures. So, in 1998, Atlas Copco Secoroc decided on a long-term ­ strategy to improve reliability, while retaining the benchmark status of the COP 64 DTH hammer. Stage One of this strategy was the development of the second generation six-inch hammer, COP 64.2, introduced in October, 2000, which incorporated newly-designed steel disc spring and lower buffer. Performance was vastly improved, thanks to a drastic reduction in the number of internal failures. It was also possible to rebuild the hammer without diminishing its performance, making it even more attractive. Stage Two was the introduction of the third generation COP 64 hammer, COP 64 Gold, which was unveiled in August, 2001. This version offers sustained performance and improved longevity of the external parts. The COP 64.2 resolved internal component reliability, while the COP 64 Gold has experienced a dramatic drop in the number of cylinder failures. COP 64 Gold also boasts improved sustainable efficiency, maintaining an average of 96% of original performance throughout its service life, which is a further improvement on COP 64.2. Durability improvements, thanks to the higher tensile strength of the new steel grade, are especially noticeable when the cylinder approaches minimum thickness limits. COP 64 Gold enjoys a greater durability margin than its predecessor. With the introduction of COP 64 Gold, hammer life will increase ­substantially. Less internal and ­external wear, together with a reduced minimum cylinder wear limit, are key Secoroc COP 64 Gold.

26



COP 64.2 steel COP 64 Gold steel Improvement

Yield point ReL(Mpa) Breaking strength Rm(Mpa) Hardness (HRc)

700 1000 32

1400 1950 42

100% 95% 31%

Table 1 reveals not only that the yield point for the new steel grade is twice as high, but also that breaking strength has been almost doubled.

Table 1 Comparison of COP 64.2 and COP 64 Gold steel.

contributing factors. The hammer is virtually main­tenance-free, with no need for an econ­omy kit in most applications. Ultimately, this means customers can look forward to increased drill rig availability. The sum total of these improvements shows COP 64 Gold to have more than 50% greater service life, in abrasive rock conditions, than its ­predecessor. The customer benefits from lower cost/metre drilled, thanks to less downtime and greater abrasion ­ resistance, and 30-50% longer life of external parts. Higher availability results from less breakage in the threads of top sub and chuck-ends of the cylinder, and there are fewer stoppages for service and maintenance. Improved penetration rate and higher efficiency are a result of reduced friction of the piston, and a greater life cycle penetration rate is the overall reward. To sum up, the customer can drill more holes per hammer than ­previously.

Applications COP 64 Gold is a high-pressure hammer, where performance is related to air pressure. A lower limit of 12 bar for deep hole applications is a good rule of thumb. The hammer is designed

for the same types of application as COP 64.2, with special focus on highpressure applications. In abrasive formations, performance will be up to 50% better than COP 64.2, in what is an ideal application for COP 64 Gold. In soft unconsolidated rock drilling, the 12-spline chuck concept and the improved durability make COP 64 Gold the perfect hammer. High pressure yields higher productivity, and drilling pressures of 28-30 bar are not unusual. The COP 64 Gold hammer concept offers customers a tool to meet the most exacting requirements.

Hammer Cylinder The new cylinder has been redesigned in a number of important ways. COP 64 Gold boasts a cylinder made of low alloy wrought and toughened steel, a new grade with a higher combined Molybdenum and Vanadium content (4.8%) than its predecessor. The result is greater impact strength and higher wear and temperature resistance. All in all, this means greater resistance to breakage, impact, temperature and wear for the new hammer cylinder. Thanks to the new steel grade, cylinder properties have been greatly improved. Wear has been reduced, both internally and externally. Cuttings

Drilling in open pit mining

Talking Technically

Total improvement Due to wear resistance Due to wear limit change Due to less cylinder failure

Increase in service life of COP 64 Gold, which has a 50% longer life than its predecesssor.

and moving parts no longer cause the problems they once did. In effect, the service life of the cylinder has been extended con­siderably. The new steel grade possesses greater tensile strength, which means the minimum wear limit can be decreased from an overall cylinder diameter of 132 mm, to 130 mm. The result is a hammer that maintains performance far longer than its predecessor, while being, in effect, maintenance-free. Longitudinal milled slots have replaced the circular undercut found in COP 64.2. The piston now enjoys 100% guidance throughout its stroke, as op­posed to the older undercut that let it partially move freely at the end of

the downward stroke. Thanks to these slots, wear on the porting edges of the cylinder undercuts and piston has been eliminated. That means air leakage is down to a minimum, and so are noise levels! The polygon-shaped piston provides a ten-point guide system, while retaining excellent force on the bit. It is sturdier than its forerunner, fitting hand-in-glove with the milled slots to provide superior guidance and airflow all the way through the hammer. The QL 60-style chuck, together with a 12-spline bit, add up to a stronger bit shank. This is especially useful in soft and unconsolidated rock conditions, where bits tend to move axially in and out in the chuck

during drilling. This may lead to greater ­ friction between chuck and splines, causing premature spline wear. Furthermore, the increase in the number of splines, from eight to twelve, leads to greater surface contact between bit and chuck, lessening stress on the splines. The high demand for COP 64 Gold hammers, particularly in applications where performance and reliability are major considerations, has led Atlas Copco Secoroc to add the COP 54 Gold to this increasingly successful range.

by Leif Larsson

Results of comparative tests with COP 64.2 and COP 64 Gold. The COP 64 Gold drilled 50% further.

16 000 14 000

Drill metres

12 000 10 000 New Material Old Material

8 000 6 000 4 000 2 000 0 146 145 144 143 142 141 140 139 138 137 136 135 134 133 132 131 130 129 128

Cylinder OD (mm)

Drilling in open pit mining

27

Talking Technically

Selecting the Right DTH Drilling Tools Covering Every Application Atlas Copco Secoroc now has the most comprehensive range of DTH hammers, bits, and related equipment of any supplier in the world, backed by the strongest support network in the industry. Whether the call is for reliable hammers to keep investment to a minimum, or for the highest productivity to ensure maximum rig output, Atlas Copco Secoroc has the solution. The company is the only manufacturer to offer both first and second choice solutions in almost all typical DTH applications on a price vs performance basis. For premium performance and advanced technology, Total Depth and COP Gold hammers are offered. For an optimum blend of features and cost, COP and Quantum Leap can be the solution, and for high reliability at economical price, nothing beats DHD hammers.    Total Depth, COP Gold, Quantum Leap, and COP and DHD Classic hammers are also energy efficient, consuming less fuel and with lower energy cost per drilled metre than other DTH hammers.   This enormous choice of DTH drilling tools is backed by a reliable network of distributors and customer centres that offer a complete range of parts, service and support.

Relevant Applications Quarrying Companies producing in non-abrasive rock formations should consider hammers such as Secoroc Quantum Leap or Secoroc COP. Both are time-tested and field-proven designs offering good productivity and ease of service. Producers demanding the highest productivity and/or drilling in abrasive formations should consider either the Total Depth or Secoroc COP Gold hammers. These incorporate the latest technology 28

Quarrying application

and are the most reliable and productive hammers on the market. For customers who are happy with rebuilds, Total Depth is recommended, while for those who typically run hammers until they wear out, Secoroc COP Gold has unbeatable wear resistance and will be the first choice. Dimensional stone quarrying demands consistent hole straightness, and such operations typically use smaller size holes of 85-90 mm in limestone, granite and marble. Here the TD 35 and COP 32 hammers are the best choice Construction Civil engineering drilling subcontractors and drilled foundation contractors will be attracted to the improved performance of both Secoroc Quantum Leap and Secoroc COP hammers. Both of these balance good productivity with ease of service. For applications

demanding the finest performance, the choice will be between Total Depth and Secoroc COP Gold hammers. At the other end of the scale, rental companies will appreciate the Secoroc DHD as a tried and tested hammer that is rugged, reliable, and easy to repair or replace. Mineral Exploration Mineral exploration generally occurs in very remote locations, requiring robust hammers capable of running high pressures, in sometimes dirty environments. For true reverse circulation drilling with face collection in mineral exploration and in-pit grade control, the Secoroc RC50 Reverse Circulation Hammer, incorporating the Quantum Leap cycle, performs particularly well. Geotechnical Environmental monitoring applications will appreciate the Secoroc DHD, or possibly the Secoroc Quantum Leap or COP hammers. Drilling in open pit mining

Talking Technically

well bore with final diameter of 6.5 in. For these projects, performance, reliability and availability of service and support become most important. Once again, Total Depth, with its Air-Select System, is the fastest and most reliable, with a minimum of maintenance.

Selecting the Right Hammer

Changing a Secoroc bit.

Drilling of holes for foundation, anchoring or drainage demands reliable, inexpensive hammers like the Secoroc DHD range. Open Pit Mining Mining operations typically have high equipment utilization, drilling up to 80% of the working day with DTH. The typical applications are normal 130-203 mm-diameter blast holes, 140165 mm buffer holes, or 115-140 mm Clusterdrill for construction work

pre-split holes. Companies should consider either the Total Depth or Secoroc COP Gold hammers. These incorporate the latest technology, and are the most reliable and productive hammers on the market. For customers who are happy with rebuilds, Total Depth is recommended, while for those who typically run hammers until they wear out, Secoroc COP Gold will be the first choice. Well and Geothermal Water wells generally use a larger diameter, cased and sealed surface section, followed by a 70-250 m-deep and 4.56.5 in-diameter drilled well bore. For smaller, family-run companies, the ideal hammer will last as long as possible, with minimum maintenance. For larger companies with more rigs, performance, reliability, and availability of service and support become more important. Geothermal drilling is similar, but may be carried out in remote locations, so the emphasis may be on the need to keep the hammer working as much as possible. Once again, Total Depth, with its Air-Select System, is the fastest and most reliable, while Quantum Leap and Secoroc COP offer excellent performance with minimum maintenance. Shallow Oil and Gas (CBM) In this application, the customer uses a larger diameter 12.25 in - 17.5 in cased and sealed surface section, followed by a 500-2,500 m-deep drilled

Drilling in open pit mining

The optimum range of hole size for DTH drilling is 90 mm to 254 mm. Smaller holes are generally drilled using tophammer, and larger holes generally use rotary machines. However, DTH has an expanding position in the larger hole sizes up to 750 mm. As a rule of thumb, the smallest hole diameter a DTH hammer can drill is its nominal size. A 4 inch hammer will drill a 4 inch (102 mm) hole. The limiting factor is the outside diameter of the hammer, because, as hole diameter reduces, airflow is restricted. Maximum hole size for production drilling is the nominal hammer size plus 1 inch, so for a 4 inch hammer the maximum hole size is 5 inch (127-130 mm). Choosing the right hammer is largely determined by hole size and type of rock formation. Ideally, the size of the hammer should match the required hole dimension as closely as possible, leaving just enough space for cuttings to evacuate the hole. Secoroc hammers are purposematched for all rock types and applications. Where high performance is the main criterion, Secoroc COP Gold and Secoroc Total Depth hammers are recommended. In deep hole drilling applications, the Total Depth hammer has proven superior performance and adaptability to different air requirements, thanks to the Air-Select System. Where proven technology is required, the Secoroc COP and Quantum Leap hammers are known for their reliability and longevity, and for a reliable workhorse, the Secoroc DHD is practically bullet proof, with a 30 year history of continuous improvement. The Standard design for COP 54 and COP 64 Gold hammers can be used down to a depth of 330 ft (100 m) 29

Talking Technically

using a Standard bit size, making it useful for production drilling in quarries, shallow waterwell drilling, and underground blasthole drilling. HD is similar to Standard, but with heavy duty chuck and wear sleeve, and a top sub fitted with tungsten carbide buttons for wear protection in harsh and abrasive conditions. These also protect the top sub from excessive wear when rotating out of the hole through broken rock.

Selecting the Right Bit Atlas Copco Secoroc has a comprehensive range of DTH drill bits to match all conceivable applications. Each bit is made from quality alloy steel, and has been precision machined to produce a perfect body, heat treated to the required hardness, given surface compression for fatigue resistance, and fitted with precision buttons manufactured inhouse. Five basic designs are available: CV Bit, FF Bit, SpeedBit, CC Bit, and Rocket Bit. These are designed for specific applications for all rock types, hardnesses and conditions. Bit life and rate of penetration are the most important criteria in selecting the right bit for a particular application. In most cases, the focus is on productivity, so the fast cuttings removal

Waterwell drilling.

features of the SpeedBit and Convex/ Ballistic designs are preferable, to ensure the buttons are cutting clean, with the minimum of re-crushing. In hard and abrasive formations, however, the flat front (FF) HD design offers best bit life, having strong gauge rows with large spherical buttons which are easy to regrind and maintain. The SpeedBit offers improved productivity with the same gauge as the FF HD, but with ballistic buttons in the front for faster penetration. An alternative is the Concave design with spherical buttons.

The Rocket Bit can be dressed with ballistic buttons for use in soft to medium hard formations where fractured rock can be expected, or can be supplied with spherical buttons for hard and abrasive formations. Bits are manufactured to match all diameters of Atlas Copco Secoroc hammers.

Secoroc hammers highest performance The Secoroc COP Gold and Total Depth hammers are designed for the most

Bit designs and rock types.

Soft rock

Medium hard rock (220 Mpa/32000 psi)

Hard rock

Flat front HD SpeedBit Convex/Ballistic Concave Concave DGR Rocket bit ballistic Rocket bit spherical

30

Drilling in open pit mining

Talking Technically

Bit designs

Facts Convex/Ballistic front design Convex front with large cutting grooves and ballistic gauge and centre buttons. For soft to medium hard non-abrasive formations. The bit is designed for maximum penetration rate. Also, an alternative in hard abrasive formations, if high penetration rate is called for. SpeedBit Flat front design/ballistic centre buttons. Flat front with spherical gauge buttons and ballistic centre buttons. For high penetration in medium hard to hard abrasive formations.

Flat front design – HD Flat front with large spherical gauge buttons for hard and abrasive formations. Also, front flushing grooves for efficient cuttings removal.

demanding drilling conditions and for those applications requiring premium performance. These hammers feature state-of-the-art technology and deliver both maximum productivity and profit. Secoroc COP Gold • Superior longevity and reliability. • Easy to service and rebuild. • Best suited for production drilling because of its excellent external wear resistance and longevity. • Internal components coated for wear and corrosion protection. Permits multiple rebuilds. • Three start chuck thread for easy bit changes. • Bit replacement possible without using drill rig break-out chains and wrenches. • Unique air cushion reduces wear and tear on drill string and rig.

Concave front design – HD Concave front with spherical buttons, with larger gauge buttons. Ideal for medium hard to hard, abrasive and fractured formations.

Secoroc Total Depth • Provides the industry’s highest power output. • Best suited for deep hole applications. • Industry-leading simplicity and serviceability, resulting in very low operating costs. • Features modular components, snap-in cylinders, a reversible casing, backhead saver sleeves, and many options. • The hybrid valved/valveless design maximizes air compressor productivity.

Concave DGR front design Concave front with double rows of spherical gauge buttons. Only available for 8 in bits and larger. The reinforced gauge gives superior protection in medium hard to hard, abrasive and fractured formations.

Proven Technology Secoroc COP and Quantum Leap® hammers combine strong performance with years of field proven technology. These hammers are known for reliability and longevity.

Concave front design Concave front with spherical buttons Perfect choice for medium hard to hard, less abrasive, fractured formations. Minimizes effect of hole ­deviation.

Rocket bit Super high penetration in soft to medium hard formations with low silica content. The Rocket bit also handles difficult formations with clay intrusions where other bit designs will not work.

The Secoroc range of DTH bits ensures that every driller can demand a solution for every application.

Drilling in open pit mining

Secoroc COP • Mainly used in mining, including underground, quarrying, and geothermal well drilling. • High reliability. • Internal components coated for wear and corrosion protection. • Can be rebuilt frequently for longer service life. • Three start chuck thread for easy bit changes. • Unique air cushion reduces wear and tear on drill string and rig. 31

Talking Technically

Secoroc Quantum Leap® • The industry’s first hybrid combination of valve and valve-less air cycle. • Mainly used in water well deep hole, production drilling and large diameter construction projects. • Wide range of available diameters. • Many options, including Hydrocyclone® and bit retrieval systems for application flexibility. Reliable Workhorse Secoroc DHD hammers are practically bullet proof, having been proven by continuous, successful operation in the industry for over thirty years. Secoroc Classic DHD • Many parts are common to those used in the Secoroc Quantum Leap®. • High reliability. • Cost-effective. • Time-tested performance

Selecting the Right Tube Key features of a high quality DTH tube are durability, accuracy and manageability. Atlas Copco Secoroc tubes are made from cold drawn tubing, providing a superior surface finish and tolerance compared to conventional tubes made from hot rolled tubing. This drastically reduces the risk of scaling from the tubes entering the hammer, a major cause of premature hammer failure. The joints are friction welded to achieve maximum strength, and the threads of the end-pieces are heat treated for optimum durability and strength of the thread profile. This not only ensures long thread life, but also makes coupling and uncoupling quick and simple, reducing drilling time. Tube diameter should be close to the hammer diameter to provide optimum flushing, reducing the chances of getting stuck. In most applications, Atlas Copco Secoroc standard API threads will be the best choice. Atlas Copco Secoroc also offers a wide range of subs and crossover subs to meet an array of demands, all manufactured to the same standards as the tubes. 32

Secoroc COP 54 Gold Express - the production driller´s best friend.

Quality API grade N-80

Standard tubes

End pieces and adapters

min 550

min 550

Tensile strength

N/mm2 N/mm2

min 650

min 700

Elongation A5

min %

18

21

Core hardness

HB

190–230

210–250

Surface hardness

HRC

Lower yield limit

Drill tube OD (mm)

Wall (mm) RD 50

23/8" 23/8" 27/8" 27/8" 31/2" API Reg API IF API Reg API IF API Reg

70

3.6

76

3.6

■

■

58–62

■

76

5.6

■

89

3.7

■ ■

89

5.7

102

5.7

114

4.3

114

5.7

■

114

7.9

■

■

■ ■ ■

■

Drilling in open pit mining

Talking Technically

COP Backhammer The COP Backhammer is a tool that can save and recover a drillstring stuck in a hole. It can be easily fitted in a suitable tube joint between the drill support and the rotation head to provide an effective combination of backward hammering and vibration to loosen stuck drill strings.

Service and Support Atlas Copco Secoroc service, support and training follows every purchase, to ensure that customers extract maximum productivity from their drilling operations. Having a knowledgeable and available Secoroc drilling engineer on site or on-line makes the difference between going it alone and tapping the experience and knowhow of a world-class partner. For example, Secoroc knows that using higher productivity bits reduces the cost of each drilled hole, and the

With on site support, the choice of DTH equipment is even easier to make.

simplest way to cut costs is to drill holes faster. This has been a focus of product development, and is at the core of Secoroc technology, ensuring that every generation of products drills faster and more efficiently.   It takes a support team to apply this knowledge, so that customers can be assured they run a profitable and efficient

drilling operation in an increasingly competitive business climate.   The bottom line is that the customer can count on Secoroc service and support, supplied by the largest, most dedicated manufacturer of DTH drilling tools in the world.

by Leif Larsson

Premium Plus DTH Bits - tough bits for a tough life The latest Atlas Copco Premium Plus DTH bits address the age-old problems of shanking and chunking, making them so uncommon as to be considered rarities. Since their introduction, a 10-30% increase in life has been reported for Premium Plus DTH bits over their predecessors, with up to 50% in some formations! Add a 5% increase in penetration rate, and this range represents the best DTH-bit concept on the market. The design uses a tougher steel grade for improved fatigue properties. Furthermore, the buttons have been positioned for faster penetration, and protrude more, for improved cuttings removal, less secondary crushing and easier bit grinding. To reduce the risk of jamming in the hole, the taper on the bit head is shorter, with a larger clearing. The Premium Plus range offers bits for 4/5/6 inch hammers, available in the following configurations: Flat front HD, SpeedBit, Convex front with ballistic buttons and Concave front.

Drilling in open pit mining

33

Talking Technically

The Economic Case for Routine Bit Grinding Cutting Hole Costs The button bit was originally developed to do the job of an insert bit, without the necessity for frequent grinding. However, it was soon found that the service life of a button bit increased considerably if the cemented carbide buttons were ground. Nowadays, it has become extremely important to grind button bits at proper intervals, in order to extend the service life of the rock drilling tool, maintain penetration rates, and drill straight holes. In all rock excavation operations, the cost is usually ex­pressed in cost per drilled metre (cost/dm), in cost per cubic metre (cost/cu m), or in cost per tonne. The cost to produce a hole depends on how fast it can be drilled, and how many tools will be consumed. The cost to produce a cubic metre of rock is dependent upon the cost of the hole, and the cost of blasting. If the blasthole is of poor quality, then more explosives will be consumed in blasting the rock. Unsharpened bits very often give a poor quality hole with deviation. Grinding constitutes around 2% of the costs of the entire drilling operation. To run the business without grinding could multiply this cost, with up to 100% added when production losses are taken into account. Labour and material are the highest costs, while the machine investment cost is low when ­utilization is high, with a large number of bits to be ground.

Grinding Methods There are two different methods of bit grinding to restore the buttons. The preferred method uses a diamond coated profiled wheel, and the other, a grinding cup. The profiled wheel provides a smooth and efficient grinding oper­ation, 34

The Secoroc Grind Matic BQ2 grinding machine can handle drill bits up to 127 mm in diameter.

which, throughout its life, maintains the correct button shape and pro­trusion. It features correct centring on all but­ tons, producing a high quality cement­ ed carbide surface, with no risk of cemented carbide nipple. Long bit life, and higher penetration rates, will result from good grinding quality. Disadvantages of using the grinding cup are that it may produce an incorrect button shape and protrusion. It is diffi­ cult to centre the grinding cup over the gauge button, and there is also a risk of producing a sharp cemented carbide nipple on the button, and a possibility of scratches due to the larger diamond grain used. Reduced bit life will result from poor grinding quality. Several tests have been carried out to find which method gives the best bit performance. The grinding wheel gives the correct shape to the button, regardless of the amount of wear on the wheel, ensuring that the bit will

Diagram 1: Typical bit life grinding at different intervals.

700

Total bit life drill metres

600

10 regrindings per drill bit

500 400 300 200

Grinding interval drill metres

100 0 10

20

30

40

50

60

Drilling in open pit mining

Talking Technically

break away and circulate in the hole, causing secondary damage to the but­ tons. When a bit doesn’t show any vis­ ible wear flat, it may be suffering from micro cracks on the cemented carbide surface. This is known colloquially as snakeskin, and can be clearly seen when using a magnifier. In this case, the surface has to be ground away, otherwise the micro cracks lead to more severe damage on the buttons. Likewise, buttons which protrude too much must be ground down to avoid damage (diagram 2).

Penetration Rate

Diagram 2: Risk of total loss when a bit is overdrilled.

achieve standard penetration rate throughout its entire life. It has also been shown that bit life is increased considerably when grinding wheels are used, rather than grinding cups. Wheels also excavate steel around the button, simplifying the grinding task, and giving the bit a more exact profile.

There is always a sharp edge cre­ ated on the button, and this becomes sharper the more the bit is overdrilled. This sharp edge, especi­ally on ballistic buttons, is very brittle. Once the edge cracks, pieces of cemented carbide

When the right bit has been chosen for the rock condition, it will provide maximum penetration rate, along with acceptable hole straightness. In rock conditions like Swedish granite, with a compressive strength of around 2,200 bar, the bit gets a wear flat after just 10-20 drill metres, accompanied by a small drop in penetration rate. When it has a wear flat equivalent to one-third of the button diameter, the penetration will have dropped by 5%. If the bit is used further until it has a two-thirds wear flat, the penetration

Diagram 3: Penetration rate drops as the button profiles flatten.

Bit Life With so many parameters involved, it is difficult to estimate bit service life. First, a proper grinding interval must be established, preferably at the stage when the button has a wear flat of one third of the button diameter. When the number of drilled metres to reach this stage has been established, then a calculation of bit life can be made, by multiplying by the number of times it can be reground. As a general rule, a bit can be reground 10 times, but smaller bits may achieve slightly less than this figure, while larger bits may achieve more. So, if the grinding inter­ val has been established as 60 drill metres, then the average bit life will be 660 drill metres (diagram 1). If a bit is overdrilled, and the wear flat is more than half of the button diameter, there is a tendency towards cracked buttons. Drilling in open pit mining

35

Talking Technically

9 8 7

Labour cost

6

Grinding material cost

5

Machine cost

4 3 2

Annual grinding volume – buttons. Figures

1

on the left side of the diagram show cost per 100 000

75 000

50 000

25 000

10 000

5 000

0

button in SEK.

Cost of grinding reduces dramatically with volume.

will have dropped more than 30% (diagram 3). When a bit has a heavy wear flat it tends to deviate, and, by the time it reaches the bottom of the hole, it will have deviated far more than planned. As a result, the blast will produce coarse fragmentation, and much sec­ ondary blasting may be required. In slope hole drilling, it is of utmost importance that the holes are straight. If the holes deviate, the slope walls will be uneven, making rock reinforcement more difficult than expected. Rock formations with different layers and joints are often character­ ized by heavy hole deviation, putting extra stress on the remaining rock tools in the drillstring. A sharp bit always Diamond grinding wheels.

36

cuts better, and will prevent both devi­ ation, and its disadvantages.

Grinding Machines Two parameters guide the selection of the right grinding machine: the number of bits to be ground; and whether the machine should be portable or sta­ tionary. Several kinds of grinding machines are available to satisfy these parameters. In most cases, a simple machine will suffice for a small opera­ tion, grinding only a few bits. The semi-automatic machines are more suitable for larger operations, such as mines and construction sites, where the machine can be stationary, and the rocktools can be brought to it.

Grind Matic HG is a water or aircooled handheld machine for grinding cups. Both spherical and ballistic cups are available. The machine is driven by up to 7 bar compressed air, and is suit­ able for a small grinding operation. Grind Matic Manual B is an airdriven portable grinder using dia­ mond-coated grinding wheels for spherical and ballistic buttons. The machine is mounted in a box fitted with wheels and handles for easy set up. It is mainly for threaded button bits, but small down-the-hole bits can be ground in this machine. A steel spring is mounted in the profile of the grinding wheel, where it functions as a centring device, allowing for easy grinding. Grind Matic Manual B-DTH is sim­ ilar to the Grind Matic Manual B. It is mainly intended for down-the-hole bits, but can also be used for threaded bits with a special bit holder. As an optional accessory, the machine can be equipped with a belt grinder for gauge grinding. Grind Matic BQ2 is the latest semiautomatic machine, with many fea­ tures such as auto-indexing device, timer control, automatic feed, and an automatic centring arm. These features, coupled to an ergonomic design, ensure high productivity, and the machine is designed to handle large volumes of threaded button bits. Cooling water is recycled after the

Grind Matic Manual B.

Drilling in open pit mining

Talking Technically

Grind Matic Manual B-DTH.

waste product has been separated in a container. Grind Matic BQ2-DTH is the latest grinding machine for mainly Comparison of grinding wheel with grinding cup.

Grind Matic BQ2-DTH.

down-the-hole and Coprod bits. It can also be used for threaded bits with a special bit holder. The machine has the same features as Grind

Matic BQ2, and can grind bits up to 7 in-diameter.

Grinding Advice The Grind Matic machine’s secret of success is that both the grinding table and the diamond grinding wheel rotate. The result is perfectly ground button surfaces, regardless of whether the buttons are spherical or ballistic. In addition, the machine’s unique diamond grinding wheel is designed to ensure even wear on its grinding sur­ face, while still retaining its profile. This, in turn, guarantees the button shape throughout the life of the wheel. Secoroc’s advice is to use Grind Matic grinding machines, with profiled diamond grinding wheels, for grinding button bits. It is the only solution able to consistently deliver perfectly shaped buttons on customers’ bits. Correct grinding is important for every drilling operation, particularly in these days of cost consciousness and fierce competition. It can make a world of difference to the bottom line.

by Bo Persson

Drilling in open pit mining

37

Talking Technically

Ergonomics and Safety Drilling Efficiency Efficient drilling is a function of many individual aspects, both mechanical and human. While it is necessary to have a powerful and easily-manoeuvrable drill rig, it is also important to take good care of the operator’s needs, and those of the external environment. What value is a machine that is too noisy, or cannot be operated in harsh weather? Operator comfort and safety has to be planned into the modern drill rig at the drawing board stage of design. To get maximum return on investment, the owner needs to be sure that the drill rig is designed to work in all conditions, without the operator getting unduly tired, and with minimum disturbance of the environment in the neighbourhood of the site. All Atlas Copco drill rigs are designed with these parameters in mind. In addition, a whole array of options is available to control the inclination, alignment and depth of drillholes, in order to get the maximum rock breaking effect from the minimum drilling effort, reducing noise and dust, and saving time, money, and materials.

Operator’s Cabin The interplay between man and machine starts in the operator’s cab, and Atlas Copco has spent a great effort in the development of a well conceived, purpose-built cab. Even the smallest details have been considered to produce a modern workstation, not only in terms of mechanical function, but also paying attention to the requirements of ergonomics, safety and the environment. The cabin offers a superb view of the drillhole from the operator’s seat, facilitating accurate collaring and control of the drilling operation. The angled, laminated glass windscreen is equipped with a large wiper, as are the right hand side and roof windows, and improved air ventilation effectively clears condensation mist from all of these windows. A jumbo-sized rearview mirror gives good visibility and safer rig moving. For 38

Perfect view from the operator’s cabin on ROC series drill rigs.

additional safety a back camera may be installed. In addition, the spacious cab gives good moveability and comfort for the operator, with easy-to-read instrumentation that is simple to learn and to use. A mechanized tube-permutation system enables any damaged drill rods to be identified from the operator’s cab. The service hatches are easily accessed, but are also lockable, as a good security precaution at isolated worksites. The cabins are even equipped with a 12-volt outlet for mobile telephone.

Ergonomics and Environment The cabin is laid out so that the operator can monitor and control the entire

drilling process without changing body position. This relieves neck, shoulders and back from strain. The ergonomically-designed seat is vertically and laterally adjustable, with control levers and control panel located in, or in close proximity to, the collapsible arm rests. The seat is slewable for easy entry into the cab, and the door is fitted with a safety stop that prevents crushed fingers. Good insulation affords a noise level below 80 dB, and rubber-damping of the cab mounting reduces vibration and gives greater comfort during tramming. The cabin has an efficient CFC-free air conditioning system for both cooling and heating, and many surfaces are textile covered for greater comfort. The cab Drilling in open pit mining

Talking Technically

in the vicinity. To achieve this, it is crucial to collar the hole on the right spot, maintain the correct alignment, and drill to a pre-determined level.

Depth Control

The HQS system uses a rotating laser beam to provide a reference plane for hole depth.

complies with the European and international safety demands for Roll-Over Protective Structure (ROPS) and Falling Object Protective Structure (FOPS). With regards to the environment, exhaust emission values of all new Atlas Copco drill rigs are in compliance with latest international standard, as are the noise values. There is efficient dust collection and coarse separation, the feeds are fitted with collectors for lubricating oil, and biologically degradable hydraulic oils are available as options.

Hole Alignment Regulations governing rock blasting in open-air excavations are found in countries all over the world. Rock excavation by drilling and blasting is a particular menace in quiet, urban areas, and it is strictly governed with respect to allowable levels of pressure shocks and ground vibrations. Productivity, and the need to control ground vibrations, means that capable and precise instruments are required to guide the driller. Faults in blasthole direction, hole deviations, and variations in hole depths must be minimized, if efficient production is to be obtained. Instruments for angle setting and hole depth control increase drilling accuracy and reduce human error. There are various ways for a contractor to comply with the blasting rules, without increasing costs for rock excavation. Several benefits can be obtained from improved blasthole alignment and Drilling in open pit mining

drill depth control. Improved accuracy in the application of the drilling pattern saves time, drillmetres, and explosives. At the same time, less boulders need to be broken, and less crushing of oversize is required. All this means reduced operating cost, and money saved. A modern hole alignment instrument offers: more precise drilling with a reduction in cost/hole; automatic depth control; better fragmentation; automatic drill feed stop; flat benches after blasting; and less overdrilling. By guaranteeing a perfect blast result, there is no need for the contractor to return and clean up rough surfaces, or condition overbreak. Much blasting inconvenience can be reduced by special drilling patterns, which distribute the explosive charges evenly, and limit the level of ground vibrations, so as not to harm property

The alignment instrument confirms the hole angle, while a laser sensor monitors drilling to the proper depth, regardless of the surface conditions. All this comes together for a successful blast, breaking rock to a level floor, with minimum ground vibration, and even fragmentation. The angle setting instruments, used with the aiming device, help set the correct angle of inclined holes. The angle and hole depth reader function controls the length of a blast hole, from the start of the hole on surface, to the preset bottom elevation. The instrument does not require any assistance from the operator, and comes with an automatic drill feed stop function for optimum drilling accuracy. The instruments feature automatic compensation, regardless of the drilling surface ground conditions. A beacon, mounted on a tripod, generates a horizontal reference plane across the worksite by a rotating laser beam. A sensor, fitted to the rock drill cradle, reacts to the signal generated by the rotating laser beam. The HQS 12 instrument provides a reference plane for all holes, automatically adjusting hole depth to match the plan, with an accuracy within 5 cm. Blasting creates a bottom elevation with an optimum flat surface.

Angle and hole depth screen display.

39

Talking Technically

Dust Control

Dust collection arrangement on ROC F7.

Easier Drilling Atlas Copco ROC crawlers are designed for stable and accurate positioning of the drill holes, featuring a rugged carrier, with a flexible boom system mounting a rigid feed beam with double drill steel supports for the drill rod. Hydraulic drillsteel supports are used for safe and easy jointing and breakout of the drillstring. Fitting a double drillsteel support allows the operator to raise the sliding support for better visibility of the collaring surface, and for simplified evacuation of water from the drillholes. This also results in easier disconnection of the drillbit where the surface rock is broken up. The double drillsteel support also contributes significantly to the straightness of the drillhole, by guiding the drillsteel at the critical collaring stage, and throughout the drilling of the hole. Inclination instruments provide the opportunity of achieving rapid and accurate alignment in the drilling direction and hole inclination. The devices are mounted on the feed beam of the drilling unit, and can be read from the driller’s position next to the feed beam, or from the rig cabin. The least deviation from the desired hole inclination is clearly illustrated on the dials 40

of the instrument. Hole depth and drilling angle are also easy to set and adjust. Atlas Copco has a very fast and well proven rod handling system that saves on operator time. The system also relieves the operator of heavy lifting work, helping maintain high productivity. It is well-proven, and is standard on crawler rigs fitted with an operator’s cab. A winch set simplifies driving, and secures the set up, in steep terrain where wet clay, snow or ice may create a risk of slipping. The winch set includes a swing arm with winch and traction controls.

The DCT range of dust collectors creates a dust-free working environment, for the benefit of both personnel and equipment on site. Some 80% of all the drilling dust is initially separated in a coarse strainer, and the remainder, including highly injurious particles less than 5 micron in size, is effectively separated in the filter unit. DCT dust collectors operate continuously and automatically. Most versions commence dust separation as soon as the flushing air control for the rock drill is opened, and filter cleansing occurs automatically when the control is closed. The drill dust and cuttings empty straight into a plastic sack, or alternatively through a rubber dust collector. Dust collectors ensure dust-free worksites, are efficient and reliable, and boost flushing capacity. They can be airpowered or hydraulic operated, and result in improved productivity. When drilling with larger bits, or when drilling in formations carrying water, the cyclone-type precleaner extends the use of the dust collector, and the service life of its filter system. A water mist system is available to provide a better working environment. Water is injected into the airflow to stabilize the hole and bind the dust on the ground.

by Lennart Lundin

Improved cabin layout.

Drilling in open pit mining

TALKING TECHNICALLY

Rotary Club Expands with Thiessen Part of Secoroc Atlas Copco recently finaliezed the aquuisition of Canadian drilling consumables manufactures Thiessen Team. The company has become part of the Secoroc division and will operate under the Atlas Copco brand.

High Quality Products Drill string components, including the drill string itself, are manufactured by Thiessen. The acquisition means that Atlas Copco is now able to offer a complete range of surface rotary drilling equipment from drill rig to Tricone bit. For more than 50 years, Thiessen Team Rotary Drilling Products has successfully serviced its global customer base with innovative, high quality products and dedicated service. Their product range includes sub-adaptors, drill strings, breakout wrenches, roller stabilizers and deck bushings. The acquisition of Thiessen includes the company’s global manufacturing and refurbishment facilities with centres in Canada, Australia, South Africa and Chile. “We are delighted to welcome Thiessen.” Graeme McKenzie, Product Line Manager – Secoroc Rotary Drilling Products.

DRILLING IN OPEN PIT MINING

Perfect partners: a Thiessen EZ-Drill Roller Stabilizer and a Secoroc Tri-cone bit.

“We are very happy to include the well-known Thiessen products in our range,” says Graeme McKenzie, Product Line Manager of Secoroc Rotary Drilling Products. “The products fit very well with our own Tricone bits and have the same high quality.” On the significance of the acquisition to Atlas Copco’s Construction and Mining Technique division, Bjorn Rosengren, Business Area President commented: “It will allow us to further develop our rotary drilling consumables market for surface mining and strengthen our position in raise boring

Rugged, repairable and with a replaceable inner sleeve: Thiessen’s Centeroll rotary deck bushing.

consumables. It will also help us to increase our customer share with key customers.”

Acknowledgements This article first appeared in Mining & Construction No 2, 2006. ■ 41

Talking Technically

In Search of the Right Balance Exploration Drilling Chips or cores? That’s the question often faced by geologists and contractors in deciding which method of exploration drilling will get the most effective and economical results. These days, the answer is quite likely to be: “a combination of the two”.

Selecting Method Since man first started searching for minerals and precious metals, three key factors have consistently proved decisive for success: time, cost and confidence. In other words, the time required, the cost of getting the job done, and confidence in the quality of the samples brought to the surface for analysis.   This is more a question of basic technology and logic than one of science. But it is interesting to see these three factors expressed as a mathematical formula: confidence over time multiplied by cost, equals profit. With profit, as always, as the driving force.   Conventional core drilling – the technique which produces cores of subsurface material – is the most commonly used method of obtaining information about the presence of minerals or precious metals as well as rock forBy Jan Jönsson, Product Manager, Atlas Copco Craelius.

42

Chips from RC drilling can be an alternative to conventional cores.

confidence = profit time x cost

mations. However, reverse circulation drilling (RC) – which produces samples as chips – is gaining ground.   The reason is easy to see. RC drilling is a faster and more economical way of “pre-collaring” in order to get down to where the orebody is located. Once there, the driller can then decide whether to continue with RC drilling to extract chips for evaluation or whether to switch to a diamond core drilling rig to extract cores. In this way, RC drilling becomes the perfect complement to conventional core drilling (see fig 1).   Selecting which method to use for actual sampling work depends largely on the preference of the geologist. But it also depends on the confidence that he or she places in the quality of the samples. Today, RC drilling has become so advanced that more and more geologists believe that chips are perfectly sufficient as a means of determining ore content. The commercialization of RC drilling started in the 1980s but the technique has certainly been around for much longer.

Early birds As early as in 1887, Atlas Copco Craelius had developed a rig that could “take” cores at depths of 125 metres. Confidence in these samples among geologists was also at its highest possible level. They were able to evaluate a piece of solid rock. Time was not necessarily of any great importance and consequently neither was cost. Manpower was inexpensive and readily available.   However, the demand for such products quickly increased and availability had to keep pace. This is very much the case today with sharp market fluctuations and so technology innovators have to find ways to optimize profit in all situations.

The time factor Hammer drilling with down-the-hole hammers was invented in 1936. It became popular during the 1970s mainly for water well drilling applications. But it was soon clear that the method was also very useful for prospecting. The cuttings were already there at the top of the borehole and therefore it was possible to make an initial evaluation on the spot. Drilling in Open Pit Mining

Talking Technically

  Hammer drilling offers a considerably higher drilling speed compared to core drilling. To use this method and further develop it to increase the performance became an obvious task for R&D people. The higher air pressure and high availability of the hammer are two factors that make it possible for technicians to speed up the “journey” down the hole.   Another factor is the durability of the bit inserts. The more metres drilled with the same bit without having to take up the drillstring, the more effective the time on the hammer.   Another factor, and perhaps the most important of all, is the logistics surrounding the drilling programme. The availability of parts, fuel, casing, water, consumables etc., has a direct influence on the number of metres drilled per shift.   Significant time savings can be achieved by using RC and core drilling in a balanced combination (see fig 2). Here we can see that one RC rig can be used to drill enough pre-collars to keep three core drilling rigs running 24-hours a day. The time factors show obvious time benefits using a combination of the two methods. In this scenario, a minimum of 25 per cent of the total metres drilled were specified as core drilling.

The cost factor The cost perspective does not have any negative surprises in store as the costs are mostly related to the time factor. The investment in RC rigs and equipment is higher compared to those of core drilling. But as we can see from the table in fig 3, the costs are reduced when a combination of the two methods is used.   In this example, we can see that time as well as costs are in favour of RC drilling. The figures are obvious and easy to evaluate and vary depending on the location and the local conditions. But the relativity remains the same and is strongly reflected in the development of the exploration drilling process.   So, how can we further shorten time and cost in the future? Immediate results from on-site evaluation is one Drilling in Open Pit Mining

IV

II

III

I

Fast and economical RC drilling without taking samples. Precollaring

Mineralized zone: Chip samples from RC and / or cores for evaluation. Figure 1. Based on geological data from the boreholes I and II, substantial savings can be obtained when drilling boreholes III and IV.

Total drilling programme 80 holes, 400 m deep. Total 32,000 m of drilling (fig 2). Scenario 1 100% core drilling 457 days

70m core / 24 hours with 1 core drilling rig

Scenario 2 50% RC (pre-collars only), 50% core drilling 301 days

70m core / 24 hours with 1 core drilling rig

Scenario 3 75% RC (pre-collars & full holes), 25% core drilling 223 days

70m core / 24 hours with 1 core drilling rig

In case three core drilling rigs would have been available in scenario 1, expected time is 152 days compared with 457 days. In case three core drilling rigs would have been available in scenario 2, expected time is 149 days compared with 301 days. A rough conclusion gives that the RC rig is somewhat faster than 3 core drilling rigs together.

way and a scanning process is already available although probably not yet adaptable to local site conditions. But do we need to drill at all in order to get sufficient information about the orebodies beneath us? It is the manufacturer’s challenge to develop equipment and technologies with no limits, but with the least amount of environmental impact.

The confidence factor Meanwhile, we have a third variable in our equation – the confidence factor. In-

Cost ratios (fig 3). 457 days 301 days 223 days

2,580,000 USD 1,740,000 USD 1,320,000 USD

Approx. cost of RC drilling – 30 USD / meter Approx. cost of core drilling – 80 USD / meter

vestors as well as geologists place strict demands on contractors to deliver high quality information about the geological formation to be explored.   Investors want the highest possible return on their investments in the 43

Talking Technically

100

% Rc drilling core drilling

80 60

Figure 4. Ratios between core and RC drilling. The figures reflect total exploration expenditures from national statistics for surface and underground.

40 20 0

canada

latin america

Russia china

shortest possible time. For example, whenever a gold nugget has been found, others may take over to conduct the drilling and blasting operations. As these are not the same people, the reliability of information plays a critical role.   Below, a few reasons why geologists should choose their drilling method carefully: ●  If there is no need for continuous information about the geological formation on the way down, there is no need for samples. It is just a matter of minimizing the drilling time. The geometry of the orebody is already known and just a reconfirmation of the boundaries is necessary. In this case, RC drilling is an efficient method to use. ●  A first scanning of virgin territory is being done where the goal is just to obtain a preliminary indication of possible content. In this case, the geologist is not relying on any mineralized structure or geometry. With an evaluation giving positive results, a programme of core drilling is the logical way to continue in order to bring the project to a resource / reserve status. ●  If the mineralized structure is identified but the geometry and rate of content varies, RC drilling is used as an indicator for ensuring continued grade control. ●  The geologist wants dry and representative samples in order to make optimal evaluations. RC drilling below the groundwater table was previously believed to undermine sample quality. Core drilling therefore remained the only viable method for these depths. Today, the availability of high pressure compressors and hammer tools makes it possible for RC drilling to reduce costs even for these depths.   These days, professional contractors 44

australia

Se asia

USa

deliver dry sampling down to depths of 500 m. By sealing off the bit from the rest of the hole it can be kept dry. A correct selection of shroud vs bit tolerance maintains a pressurized zone around the bit. Boosted air pressure is needed to meet the higher water pressure on its way down the hole. In addition, a dry bit drills faster. ●  It must be remembered that information from a core is crucial in estimating the period of mineralized structures. The core helps the geologist to calculate the cost of extracting the mineral from the ore. Large volumes of rock have to be excavated to obtain just a few grammes of a valuable mineral. ●  Cores also yield geotechnical data. Data about slope stability can be of the highest importance. ●  Ground conditions are naturally also of great importance and may produce Principles for RC drilling showing flow of compressed air and chips. The sampling collection box is integrated into the cyclone.

africa

questionable samples if some of the information from fissured zones is left behind in the hole and not collected. In such circumstances, core drilling could be the only alternative.

RC on the increase RC drilling is increasing. Judging by its growth rate in recent years it may well account for 55 per cent of all the metres drilled in 2008.   Figure 4 above shows some estimated ratios between core and RC drilling in different parts of the world in 2002. In total, RC accounts for 50 per cent and core drilling for 50 per cent of metres drilled.   Tradition and the environmental impact play a large role. RC rigs are heavy, assembled on trucks or track carriers. This fact tends to favour core drilling rigs which are lighter and even adaptable in order to be flown into remote and sensitive environments.   In areas with extremely cold climates and where permafrost is present, RC drilling may have its limitations. Antifreeze rock drill oil help to keep the hammer and bottom of the hole free from ice. Other, purely practical issues determine the choice of one or the other drilling method.   An intelligent, balanced choice between the two methods is the key to optimal results.   Here, the geologist plays an extremely important role in finding this balance and so do manufacturers such as Atlas Copco which will continue to provide the right tools for the job.

Acknowledgements This article first appeared in Mining & Construction No 3, 2005. ■ Drilling in Open Pit Mining

Talking Technically

Protection by ROC CARE Scheduled Service Nowadays, drill rigs are considered to be a major capital investment, and their owners, whether oneman contracting businesses or large corporations, have to be satisfied that their investment is being correctly serviced. In this way, they can get the best possible return on investment by maximizing availability, while preserving longterm value. This is where ROC CARE, the new value-for-money service package for Atlas Copco surface drillrigs, comes into play.

Key Ingredients ROC CARE scheduled service ensures consistent drill rig performance, hour after hour, day in, day out. Supported by inspection protocols with recommended actions, and extended warranty to protect against the risk of extra costs if a major component fails, the customer is given the required service at the recommended intervals over the full duration of the agreement, for which he is invoiced at the agreed low monthly amount. This translates into scheduled service without financial penalty, encouraging both parties to concentrate on preventive maintenance rather than risk costly breakdown. ROC CARE is tailor-made for the quarry and construction business, protecting all that is essential to the drilling operation. It guarantees regular inspections and service, giving security and peace-of-mind for at least 5,000 engine hours of drilling. By focusing on breakdown prevention, rather than unplanned repair, it helps keep operating costs to a minimum.

Scheduled Service Scheduled inspection and maintenance is a key element of ROC CARE, with the drill rig being serviced according to each original equipment manufacturer’s Drilling in open pit mining

Replacing air filters at the scheduled interval improves efficiency.

maintenance schedule. ROC CARE covers all parts needed for scheduled maintenance, including oil filters, air filters and fuel filters. The service is carried out by fully-trained and professional Atlas Copco engineers, who know every part of the equipment, and can submit recommendations to prevent potential

future problems. Indeed, at each service occasion, the engineer hands the customer a detailed rig inspection protocol, reporting the rig condition and identifying any corrective measures. These can then be carried out at the next scheduled service, or at a time chosen for least disruption to production. 45

Talking Technically

ProCom knows when drill rigs next need service, allowing efficient forward planning.

Such measures minimize breakdowns and contribute to savings in overall cost of ownership. The general extended warranty that accompanies every ROC CARE agreement provides protection against the breakdown of key components, such as the diesel motor, compressor, hydraulic pumps, feed motor, traction motor and ProCom monitors rig status around the world.

traction gears. In addition, all fabricated major mechanical components such as the wagon frame, track frames, boom support, booms, boom head and feed holder are included.

ProCom ProCom, included in ROC CARE, knows

when each drill rig next needs service. It is a global, satellite-based system that monitors rig status, facilitating remote viewing of engine hours, impact hours, and time-to-service. On certain models such as ROC RRC, HEC 3, and SmartRigs ROC D7, ROC D9 and ROC F9, ProCom also transmits details of drilled metres. The system works worldwide, monitoring rigs wherever they are located. By knowing exactly when each rig next needs attention, Atlas Copco can schedule service with minimum disruption to drilling. Because every effort is made to plan ProCom inspection and service visits to cause as little drilling downtime as possible, Atlas Copco service engineers are conscious of a happier reception at site. In turn, they no longer have to plan their working lives around emergency breakdown callouts, resulting in a decrease in stress for both customer and engineer, and more satisfaction all round.

by Göran Nilsson 46

Drilling in open pit mining

morenci copper mine, USA

A Viper for the Copper King Drilling 50-ft Benches The vast Phelps Dodge Morenci copper mine in Arizona, USA, is the largest of its kind in North America, producing more than 240 million tons of blasted material per year including 31 million tons of ore. Contributing to the mine’s productivity is a Pit Viper rotary blasthole drill rig which has drilled more than 2.2 million feet in the past four years.

Ten Thousand Holes per Year The Morenci mine in the south eastern part of Arizona started its life in the late 1800s underground. Today, it is a major open pit operation and the largest copper mine in North America.   It is a massive operation covering an area of 3,055 acres, which will increase to 4,683 acres in 2006. A total of 4.37 million feet of blast hole drilling is carried out annually including 570,000 feet in ore – the ideal proving ground for the rotary rig Pit Viper 351.   Weighing 375,000 pounds, measuring 53 feet long and equipped with seven onboard computers, the Pit Viper 351 was the largest and most advanced rig of its kind on the market when it was introduced at the MINExpo show in Las Vegas in 2000.   After the fair, Morenci took the prototype and put it to work in a fleet of 16 rigs from a variety of other manufacturers. Today, four years down the line, it is still performing to expectation.   Since April 2001, the rig has been in production full time and operates on a costper-foot basis. By August 2004, it had drilled 2.2 million feet and is currently averaging about 60,000 feet per month, although in some months it has drilled more than 80,000 feet.   In fact, the rig has been so productive that the unit number “20R” has had to be changed towards the end of each year because the rig drills more than 10,000 holes per year and the mine’s automated, annual hole-numbering system stops at 9,999.   Most of the production rigs at the site are Drilling in Open Pit Mining

electric, which, due to their power cables, makes them difficult to move from bench to bench. The PV 351, however, with its Cummins 45-litre diesel engine (1500 hp at 1800 rpm) moves easily and frequently between the benches. Also contributing to the rig’s productivity is the hydraulic design that uses one gearbox and five pumps for the complete unit as well as the cable-feed system and positive lubrication oil pump for the air compressor.

The tri-cone, tungsten carbide bit: Supplied to the Morenci worksite by Baker Hughes Mining Tools, now Atlas Copco Secoroc.

Dependability Essential   The mine operates 12-hour shifts, 24 hours per day, seven days per week so rig dependability is essential. Not only is the PV 351 powerful and dependable, it is also 47

A VIPER FOR THE COPPeR KING

“We are thrilled with what we have accomplished for Morenci.” Brian Fox, VP Marketing, Atlas Copco Drilling Solutions.

sophisticated. The seven on-board computers operate via a controller-area network (CAN) to handle all of the inputs and outputs. It features production monitoring, rock recognition and GPS systems, which are designed to allow for easy technology upgrades.   A GPS navigation system enables the drill pattern to be transmitted to the rig via a radio network. The hole location is shown on a touch-screen display and guides the operator in positioning the drill to within three centimetres of its target. This also eliminates the need to manually stake holes and survey the “as drilled” location. But more importantly, it ensures that the hole is drilled where it was designed to be, in order to optimize fragmentation.   When drilling on Morenci’s 50-ft benches, typical holes are 12 inches in diameter and 57 feet deep. They are drilled in a 28-ft square pattern. Although the rock is igneous, it only takes 17 minutes to drill a hole, of which 13 minutes is actual drilling. Generally, 90,000 pounds of weight is placed on the bit. Thanks to the 350 hp rotary head, rotation does not stall, even with the heavy load. Fuel consumption is 0.174 gal/ft.   Baker Hughes Mining Tools, one of Morenci’s drill bit suppliers, has developed a tungsten-carbide tri-cone bit to handle the power of the PV 351. This HD53CA bit has an average life of 9,500 feet and this contributes to the Pit Viper’s low total drilling cost – the lowest in the Morenci fleet.   Brian Fox, Vice President, Marketing for Atlas Copco Drilling Solutions (formerly Ingersoll Rand Drilling Solutions) says: “We are thrilled with what we’ve accomplished at Morenci with the Pit Viper 351. To go from being an outsider at a major mine to being a valuable part of their production speaks well of the product design and of the capabilities of our Arizona-based support team, which keeps the rig available 90 per cent of the time.”

Acknowledgements Conversion factors 1 acre = 4047 m2 1 ft = 0.305 m 1 hp = 735.5 W 1 pound (lb) = 0.4536 kg 1 US gallon = 3.785 litres

48

This article first appeared in Mining & Construction, No 3, 2004. ■

Total control in the pit : A GPS navigation system enables the drill pattern to be transmitted to the rig via a radio network.

FACTFILE The Morenci mining district, located in southeastern Arizona, is part of a formation that extends from western Arizona to south western New Mexico and south to Mexico. Mineralisation is hosted primarily in igneous rocks. It is 85% owned by Phelps Dodge, whose share of the output accounts for one-third of its annual copper production of 1 million tons.   The operation consists of three pits: Metcalf (43 benches down, 230,000 tpd) Coronado (21 benches down, 370,000 tpd) and Western Copper (6 benches down, 50,000 tpd). At more than 2,100 feet, Metcalf is the deepest.

Drilling in Open Pit Mining

BINGHAM CANYON MINE, USA

Best Practice at Bingham Canyon Copper Giant Shine By focusing on the total effect on productivity, rather than on the technical performance of individual products, the world’s second largest open pit copper mine is getting impressive results.

Total Approach All mining companies in the Rio Tinto group met in Australia last year to discuss “Improving Performance Together.” The aim was to identify the areas of mining excellence and best practice at individual sites that could be adopted globally.   Among several shining examples was the Bingham Canyon Mine near Salt Lake City in Utah, USA.   Bingham Canyon, owned by Kennecott Utah Copper, knows a thing or two about rock excavation. Over the years, it has moved more than 6 billion tons of rock and earth to produce 17 million tons of copper – more than any other mine in history. It has also grown to become the second largest open pit on earth, after Chuquicamata in Chile.   But it is not size that has kept the mine on top. It is its management approach – a continuous focus on total productivity improvement characterized by close cooperation with sub-suppliers.   Mine Superintendent Ted Himebaugh explains: “The key element in evaluating something is ‘greatest value in use.’ We look at feet drilled per dollar spent. How much did we get out of what we bought? At this site, performance goes before bit life, and service goes beyond making the customer happy to making the most out of the product.”   Himebaugh adds that the concept of demanding continuous improvement from a supplier also goes beyond price.   One of the suppliers that consistently meets these standards is Atlas Copco, now into its second three-year contract supplying blasthole tricone drill bits and services.   The mine uses eight drill rigs equipped with any one of six different Secoroc tricone bits. Two sizes are used, 10 5/8” (trim Drilling in Open Pit Mining

blast, wall control) and 12 1/4” (production), each in three different formation types, 50s, 60s, and 70s. The 50-60-70 series denotes different hardness of the bits to suit different formations.   And continuous improvement is the yardstick against which nearly everything is measured.   Bruce Jones, Pit Superintendent says: “Every contract we do these days, from a major piece of equipment to consumables, has a continuous improvement component. We provide technical specifications that have to be met, but we also have high expectations of what service and quality should be.”   There are 17 different rock types at the site. Dan Benfield, Operations Engineer explains: “Our geological scope is so varied. It used to be the old Bonneville seabed and, if you look at it, it’s all curved and bent and twisted. So you could be going through great material for the first 20 feet of the hole, hit harder-than-heck material the next 20 feet, and then be back in really nice material again.   “Usually you get a couple of holes of good, and a couple holes of tougher material, and the white limestone is obviously the worst. You can literally punch a hole and get a penetration rate of 200 feet per hour.

The new medium formation tricone bit: Designed to stay sharp longer.

49

BEST PRACTICE AT BINGHAM CANYON

Highly personal service: Jim Wheeler, Atlas Copco Area Manager.

Ted Himebaugh, Mine Superintendent: “Greatest value in use.”

Keeping the dull bits for future improvement: Altas Copco inspects and evaluates them prior to disposal.

Valuable Resource Personal service is highly regarded at the mine and Jim Wheeler, Senior Area Manager of Atlas Copco, has been closely associated with the mine for more than 12 years. “Jim has great historical knowledge of our mining,” says Benfield. “He remembers being in this white limestone before and can pull up the data and show what we did last time. That is just invaluable, as he has data that helps us decide which type of bit we should be using.”   This high service level includes both recommending suitable bits from the extensive Atlas Copco Secoroc range as well as the development of new bits for specific tasks.   Atlas Copco also keeps the mine supplied with bits when the need unexpectedly surges. “When we hit this commercial limestone it was much harder than we anticipated,” Benfield recalls. “We went through a lot of bits, and Jim did everything to ensure procurement and non-stoppage of work up here – including getting bits from the Atlas Copco warehouse, through the factory and flying in bits from overseas.”

Inspecting the bits: Bob Endter, Sales Manager for Tricone Bits, Atlas Copco USA.

  And production is substantial: Approximately 250,000 feet (76,200 m) are drilled every month, generating 14 million tons of material that’s loaded and hauled. This is a combination of overburden and ore, the latter a low grade copper with significant quantities of gold, molydemum and silver gained as byproducts.   Improvements to date include the introduction of the MAG53C bit which has resulted in 25 per cent improvement in bit life, increased penetration rate and much lower total cost-per-foot drilled.   The mine is also testing a new Secoroc design concept – a medium formation bit with technically advanced carbide grades. This bit is designed to improve penetration rate by keeping the cutting structure sharp longer to maintain its original profile and reduce the rounding of gauge inserts.   “Bit performance tests are a good example of customer support,” says Mike Wickersham, Superintendent, Production Support. “We recently did pull down tests to see what the design of the bit could handle and Atlas Copco was involved in that. We’ve tested many different bits and the relationship has endured all those trials. Jim always works hard giving us what we want, when we want it.”   Concludes Dan Benfield: “All manufacturers should be trying to improve their product’s productivity. What I care most about is that Atlas Copco is putting time into developing new bits to increase our productivity. That’s real continuous improvement.”

Acknowledgements This article first appeared in Mining & Construction, No 2, 2005. ■ 50

Drilling in Open Pit Mining

BETZE-POST GOLD MINE, USA

Rotary and DTH Work Side by Side Steeper Slopes Reducing the amount of waste in open pit mining is the key to good pit economy. The combination of highperformance rotary drilling rigs and Atlas Copco smallhole rigs has led to new cost savings and production efficiency. The Betze-Post gold mine in Nevada is a typical case.

output to some 20 million ounces. Mineral reserves at year-end were reported to be 15.7 million ounces.   On average, the mine moves up to 430,000 tons (390,000 tonnes) of waste and ore daily, making the strip ratio – the tonnage of waste in relation to the tonnage of ore – 10:1.

The 270SP, the prototype of PV-271 Pit Viper, launched at MINExpo 2004 in Las Vegas. Fitted with onboard drill monitoring and GPS locator system, it was up and running within minutes at the Betze-Post pit.

Precise Drilling and Blasting A critical factor in a mine’s economic feasibility is the grade of the ore. For hard rock open pit mines, the amount of waste that has to be removed by drilling and blasting, loading and truck haulage in relation to the extracted ore is also a major factor in operating costs.   For gold mine operators, hauling a large tonnage of waste is a necessary evil as the low grade of the ore means that the cost per ounce of gold for haulage to the concentrator is high to start off with. To maximise profitability, it is essential to keep the amount of waste to be blasted and removed to a minimum.   Keeping the high wall as steep as possible reduces the amount of waste to be removed, thus reducing operating costs (see diagram, next page). However, keeping the rock face stable as well as steep requires precise and careful drilling and blasting.   For this reason, the Betze-Post gold mine in Nevada has recently added an Atlas Copco down-the-hole drill rig to its fleet of Ingersoll-Rand rotary DTH production units. Here, the combined fleet must work through about 4.6 million feet (1.4 million drillmetres) per year.

Steep and Stable The pit is Barrick Gold Corporation’s first operation on the Goldstrike property and mines various ore types. In 2003, Betze-Post produced 1.6 million ounces of gold at a cost of USD 232/ounce, taking cumulative Drilling in Open Pit Mining

51

rotary and dth work side by side

  The ROC L6H has been brought in to drill smaller hole sizes than the previously assembled fleet, and these smaller holes are for pre-split drilling to keep the high wall as steep as possible with a clean break.   A four-row trim is used for the high wall: three parallel lines of buffers accompany the one row of pre-splits. And the ROC L6H is drilling 4-inch holes on a 5-ft spacing using a Secoroc COP 44 hammer and Secoroc concave Speedbits. Moving from a completed hole through set-up to the start of drilling at the next hole takes 22 seconds.   Mine Superintendent Roy McKinstry says that the majority of drillers who are experienced with the Ingersoll-Rand rigs learned to use the ROC L6H quickly, most of them taking about an hour to familiarise themselves with the controls.

A New Addition Another recent addition at the Betze-Post open pit is a single-pass drill rig – the 270SP, the prototype of IR’s PV-271 Pit Viper also exhibited at MINExpo 2004 in Las Vegas.   In 1994, the mine already wanted to switch to light-weight and single-pass capable rigs that would be more powerful and up-to-date. But at that time, neither Ingersoll-Rand nor any other supplier was able to offer such a rig. With the introduction of the Pit Viper in 2000 and subsequent rises in gold prices, the mine and manufacturers were able to work together on a suitable solution.   In April this year, the 270SP went to work in the open pit, adding to the existing fleet of five IR DM-M2 double-pass units and two DM45/HP drill rigs.

Benches using presplitting and DTH drilling

ROC L6/L8

  McKinstry explains that the DM-M2 rigs normally work on 40-ft high benches, drilling 9-inch holes in patterns of 24 x 24 ft or 32 x 32 ft, and the DM 45 units on 20ft high benches, drilling 8-inch holes in 16 x 16 ft or 18 x 18 ft patterns.   The rigs typically operate in rotary mode but occasionally with Ingersoll-Rand DTH drills, bits and pipes. The penetration rate is 86–140 feet/hour, says McKinstry, but can be as high as 500 feet/hour or as low as 20 feet/hour, depending on rock hardness, which is highly variable.   According to Drill Foreman Jim Owen, when the 270SP was delivered to the mine in three sections, it was reassembled and then taken down into the pit where it was driven off the trailer and started drilling within minutes. The 270SP has been rapidly and thoroughly evaluated by the mine and by Drilling Solutions ahead of series production.   The mine’s goal is to improve precision and reduce costs by drilling longer holes. Where the standard 40-foot high benches are being mined, the rig will drill 44-foot holes. For this application, the 270SP is set up for high bailing velocity rather than high pressure and equipped with a GPS/ VDU positioning system.   Says McKinstry: “The 270SP has performed excellently, consistently drilling up to sixty 44-foot holes, almost 2,700 feet in a single shift – and that’s without pushing it anywhere near its limits.”

Impressive Performance The first IR rotary blasthole drill went into service at Goldstrike in 1988. Since then, a total of 17 IR rigs have been in service, accumulating more than 800,000 hours of

STEEPER SLOPES MEAN BETTER ECONOMY Pre-split DTH drilling using ROC L6/L8 creates higher and narrower benches. This contributes to steeper pit slope and less waste rock to be extracted. The advantage Waste excess of this is a low waste-to-ore ratio, which means higher productivity and better overall pit economy. The method has been successfully used at the Chuquicamata mine in Chile and is now being adopted in the gold mines of Nevada, USA. Benches using traditional method

For more information, see M&C 1/2002, Technically Speaking. This article is also available on the Internet at: www.miningandconstruction.com

52

Drilling in Open Pit Mining

rotary and dth work side by side

operation. Excluding the new 270SP, the other 16 rigs have operated over 50,000 hours on average. Several of the DM-M2s still in operation are at more than 65,000 hours each.   Hours pile up quickly at Goldstrike as evidenced by the new 270SP, which clocked more than 1,200 hours in just over two months of operation. The mechanical availability of this unit, less preventive maintenance, is 99.3 per cent.   Brian Fox, VP Marketing for Rotary Blasthole Drills at Atlas Copco Drilling Solutions, says: “We are fortunate to have a great relationship with Goldstrike. We are happy they patiently waited for the prototype to be developed, especially since they had so much input to its design. It is a world-class operation as evidenced by what they get out of their rigs.”   All of the IR rigs at Goldstrike were supplied and are supported by Cate Equipment Company, one of Atlas Copco Drilling Solutions’ largest dealers covering Nevada, Utah, Wyoming and Idaho. ■

Acknowledgements This article first appeared in Mining & Construction, No 2, 2004. ■

Best in test: The ROC L6H proved to be the most effective rig for pre-split drilling to keep the wall as steep as possible.

One of five IR DM-M2 double-pass drill rigs at the Betze-Post gold mine.

The 40-foot high benches at the Betze-Post open pit mine in Nevada, USA, where small-hole drill rigs and rotary units now work side by side.

Drilling in Open Pit Mining

53

LOS FILOS, MEXICO

The Golden Twins of Southern Mexico Going for Gold in Guerrero Two open-pit gold mines located 200 km south-west of Mexico City in Guerrero State, Los Filos and Bermajal – collectively known as the Los Filos Gold Project – are set to become the largest gold mining operations in Southern Mexico. Preparation work to reach the deposits, an estimated five million ounces of gold, is already under way. “Performance has matched our plans.”Roberto Díaz Colunga, Manager of the Los Filos Project.

Large Scale Project This region of Mexico has never had a large-scale open pit mining operation before. “We’re setting a precedent here,” says Roberto Díaz Colunga, Manager of the Los Filos Project, and explains: “In two years this will be the largest gold mining operation in the south of Mexico. The project already provides more than 1,200 direct and indirect jobs and once we reach our steady production rhythm, we’ll be able

to refine over 300,000 ounces of gold per year.”   The Los Filos Project is located 8 km from the village of Mezcala, approximately 200 km southwest of Mexico City in Guerrero State. The project is owned by Luismin SA. de CV, a Mexican company fully owned by Goldcorp of Canada. Goldcorp is investing USD 232 million to bring the project into production.   A fleet of Atlas Copco equipment is already working at the site, with more units due to arrive. Seven DM45HP blasthole drill rigs and two CM760D crawler drill rigs have been acquired by Luismin. The project’s main contractors, Materiales La Gloria and Desarrollos ROD, also use Atlas Copco equipment in their key preproduction tasks.   “Before entering commercial production, Los Filos will have had two years of pre-production development and Bermejal one. This is a key phase for the project and it’s important that we have the right type and quantity of equipment in place,” says José Caracheo Brunel of Los Filos Mine Planning Department.

Two Deposits, One Project United States of America

BERM

Minera Maria

BACKBREAK HOLES

MEXICO Gulf of Mexico

MEXICO CITY Los Filos Pacific Ocean

54

The project comprises two separate gold deposits, Los Filos and Bermejal, which occur in adjacent hills approximately 1,200 m above Mezcala.   A feasibility study was originally completed in 2005. This study was recently expanded to include the adjacent, and subsequently acquired, Bermejal deposit. The Los Filos and Bermejal deposits will be developed as a twin open pit, heap leach operation, using two different ore processing methods depending on grade.   The mine reserves and resources total over five million ounces, of which four and a half million ounces are in the proven and probable reserve categories. Higher grade ore (1.50 g/t of gold) from the Los Filos deposit will be crushed to 80 per cent at –19 mm and agglomerated before being conveyor stacked and heap leached,

DRILLING IN OPEN PIT MINING

THE GOLDEN TWINS OF SOUTHERN MEXICo

whereas lower grade ore (0.55 g/t of gold) from the Los Filos and Bermejal deposits will be hauled from the open pit directly to the leach pad to be bulk heap leached. The recovered solution will be treated to obtain a final gold ore product on site.   Exploration drilling continues on pit extensions and, in particular, on identifying higher grade areas.

200 m Tonnes of Ore   The mine development plan envisages a sequence of five mining phases over a 10year period for both deposits. Under the plan, a total of 200 million tonnes of ore will be mined with an average gold grade of 0.69 g/tonne and an overburden strip ratio of 1.5 to 1. The stripping will entail the removal of 300 million tonnes of overburden to access the gold bearing ore.   The project will process 24 million tonnes/year of ore. A pre-production of 14 million tonnes/year is required for each deposit. To develop the orebodies, conventional open-pit mining methods will be employed using 12–15 m3 capacity loaders and shovels and 91 to 146-tonne capacity trucks. The pit design for both deposits incorporates 12 m-high waste benches and 6 m-high production benches. Final average slope angle will be 48–52 degrees depending on the type of rock.

  “We expect almost all the material will require blasting; the reason for blasting the ore on 6 m benches is to provide better ore control and limit dilution,” explains Caracheo Brunel.   The operational cycle will start with the drilling of 175 mm and 114 mm diameter blast holes in the waste and mineral strata respectively. To achieve this, Luismin has ordered a total of seven DM45HP blasthole drill rigs. The DM45 is a high pressure, crawler mounted, hydraulic tophead drive, multi-pass rotary blasthole drilling rig specifically designed for production blasthole drilling. Operation of the drill is performed using electric over hydraulic controllers, ergonomically located so that the operator faces the drill centralizer while drilling.   Two of the seven units ordered were delivered in 2005 and are already hard at work on the site, equipped with Secoroc ballistic button bits. A third unit arrived in May with two further units arriving in June and then two more in August. “We only ordered the last five machines once the Bermejal deposit was acquired. Some of these units will work in the Los Filos deposit and some at the Bermejal deposit,” says Caracheo Brunel. “We acquired the DM45 model because it is the ideal size and capacity for the production volume we’ll be managing here.”

“This is a key phase for the project.”José Caracheo Brunel, Mine Planning Department, Los Filos.

ø 11-12 ¼" ø 6"

BERM BACKBREAK HOLES

5m

5m

72 º

PRODUCTION HOLES

6m

DRILLING IN OPEN PIT MINING

15 m

5m

The drilling and blasting pattern at the Los Filos mine showing the angle of the drill holes.

5m

55

THE GOLDEN TWINS OF SOUTHERN MEXICo

  Díaz Colunga continues: “We have also chosen these machines, both the DM45 and the CM760D, because of Atlas Copco’s proven experience. This reassures us of the equipment’s good performance to guarantee the drilling, which is the first, most important step in the whole production cycle.”   About 25 contractors are at work on the project. Materiales La Gloria – a main contractor – is a regular Atlas Copco customer and its fleet of equipment at Los Filos includes T4BH, ECM 350 and ECM590 drill rigs. Recently, the company ordered two CM780D crawlers with DTH hammers. Meanwhile, another major contractor, Desarrollos ROD, has a fleet of 15 ECM350 rigs operating at Los Filos.   Asked about the performance of the Atlas Copco equipment, Díaz Colunga says: “So far we are satisfied as their performance has matched our plans and expectations.” He notes that the project hasn’t yet reached a normal production rhythm: “We believe we will be more satisfied with the drilling results if we together look after two very important factors – the discipline in the operating habits that we transmit to our personnel, and the meticulous respect for the preventive maintenance programme. Other factors are covered by engineering design and Atlas Copco’s experience, in which we have complete faith.”

Specialist Support Specifically designed for production blasthole drilling: One of seven DM45HP drill rigs used at Los Filos to keep the project on schedule.

Demanding Topography The two CM760D crawler drill rigs with DTH hammers were delivered in 2005. “These machines are very useful. They are currently working on bench development but later we plan to use them for pre-splitting,” says Caracheo Brunel.   Díaz Colunga, Project Manager, adds: “We had seen the CM760 working before; they have the versatility needed to access this demanding topography, which doesn’t offer many possibilities of large spaces during the opening of the benches. Because of this, they are ideal for preparation tasks. Also, we required a machine able to conduct detailed work such as pre-splitting and road construction. These units are good for these jobs.”

56

Madisa, the local Atlas Copco distributor is responsible for technical support at Los Filos and is supported by specialists from Atlas Copco’s Mexicana’s office. Juan Carlos Gómez, Atlas Copco Product Manager, explains that upon delivery of a new drill rig, an Atlas Copco specialist will train operators on the use of the rig. “At the same time, Madisa sends its mechanics and instructors so they can participate in the training and become even more familiar with the machine.”   This training is now even more important for Madisa, which has secured a full Maintenance and Repair Contract (MARC) at Los Filos. Operators of the recently delivered DM45 and CM760D rigs are trained in a three-week programme and technical visits help to reinforce their knowledge.   Javier García Adame and Rosalino Carreia Soto are two of the operators of the DM45HP rotary rigs. García, who has been DRILLING IN OPEN PIT MINING

THE GOLDEN TWINS OF SOUTHERN MEXICo

operating the DM45 for nearly four months when M&C visited the site. “It was a comprehensive training process but easy to take on,” he said. “I have no problems with the machine and feel I know it quite well now.”   Carreia, who has been working at the project for six months, is still going through the training process: “There are lots of things to learn but it is not complicated at all. And the specialist giving the training is good too. I’m looking forward to finally operating the machine all by myself!”   Díaz Colunga reaffirmed the importance of the training. “We have had the benefit of the specialist training that Atlas Copco instructors have given to our operators,” he said. “I am convinced that in the future this link will be crucial to strengthening the success of our operations.”   The project is at an advanced stage of development. Construction is well under way and is expected to be completed by the end of 2006 with commercial production planned to start in the second quarter of 2007. Commercial production for that year is expected to be 200,000 ounces of gold, rising to 350,000 ounces by 2008.

Acknowledgements This article first appeared in Mining & Construction No 2, 2006. ■

Two of the 15 ECM 350 drill rigs belonging to Desarrollos ROD, which is in charge of constructing the leaching pad at Los Filos.

DRILLING IN OPEN PIT MINING

57

MINERA MARIA, MEXICO

Minera Maria’s Pre-Split Pioneer Modern Methods Open-pit mining at the revived Minera Maria mine is forging ahead. Modern surface drilling methods and efficient recovery of the copper ore are breathing new life into this once abandoned mine.

“We can’t imagine working without the ROC L8.”Humberto Garibay, Mine Manager.

The Atlas Copco ROC L8 at work in the open pit at Minera Maria.

58

  Ricardo Ornelas, of Atlas Copco Mexicana, says: “More advanced and larger equipment such as hydraulic DTH rigs have steadily been introduced into the country. The ROC L8 is a good example of this. This is the first machine of its type in Mexico for pre-splitting applications and Minera Maria is making the most of it.”

Small Diameter Holes

Reviving Maria

Minera Maria S.A. De C.V. is located in the Cananea District of the north-western state of Sonora, one of the most important copper producing states in Mexico. The operation is owned by the Frisco group of companies.   Acquisition of a ROC L8 rig by this group marks the first time that Grupo Frisco has employed drilling equipment specifically to drill small diameter holes at one of its surface operations.   “Maybe the fact that we have less competent rock at this site made us feel that there was a need for such equipment here,” says Humberto Garibay, Mine Manager. “Now that we have this machine, we can’t imagine working without it. In pre-splitting it has performed much better than we had expected, it has helped us in production blast drilling in areas where we can’t use the rotary rigs and we have planned to use it in exploration drilling to confirm proven ore reserves.”

Minera Maria was previously an underground, high-grade copper and molybdenum mine, which was in production for most of the 1990s. After depletion of reserves, the mine was closed in 1998. Grupo Frisco re-started operations in July 2003; this time as an open-pit operation achieving copper recovery through a solvent extraction electro-winning (SX/EW) process.   The final product is copper cathodes. Currently, Minera Maria produces around 88 tonnes/day of copper cathodes with a purity of 99.99 per cent.   Mining takes place in three different areas: Maria pit, the main production area, which is being exploited in four phases; La Verde pit, located northwest of the Maria pit, adjacent to what will be the fourth phase of the main pit and which currently contributes about ten per cent of the daily production; and Lucy pit, located about 9.5 km from Maria and which will be in production in the near future.

Drilling in Open Pit Mining

MINERA MARIA'S PRE-SPLIT PIONEER

  Having completed Phase I, the Maria pit is presently producing from its second and third phases. “Our production plan was designed in this manner in order to exploit the highest grade areas first and obtain the best cash flow possible from the mine during the first few years,” explains Garibay.   Given the relatively shallow depth of the pits and the great volume of low grade material that has to be moved, mining is carried out using conventional truck and shovel methods. Minera Maria moves 75,000 t/day of material, of which approximately 35,000 t/day is ore and 40,000 t/day is waste. The average ore grade is 0.42% of Cu. “So far, we have extracted about 17 million tonnes of ore from 57 million tonnes of reserves,” says Garibay.   Among the mine’s equipment fleet are 12 trucks of 150 tonne capacity and two electric shovels of 25 tonne capacity. For blast hole drilling, Minera Maria employs two rotary drill rigs with the capacity to drill 11–12 11/4 inch hole diameters. Drilling in Open Pit Mining

Pre-Split Process

Minera Maria’s ROC L8 is averaging 38 m/h, sometimes reaching 48 m/h.

In October 2005, an Atlas Copco ROC L8 rig was added to the fleet. This machine was specifically acquired for pre-splitting work, which was previously done with the rotary rigs. Today, all the pre-splitting work is done with the ROC L8 unit.   Pre-splitting is carried out by establishing a free surface in order to preserve the stability of the pit face. A series of closely spaced holes along an agreed cut line are drilled, charged and detonated prior to the bulk charges in the production area. This pre-split forms a fracture plane along the agreed extraction line and ensures that any disturbance to the rock beyond the agreed line of extraction is minimal.   At Minera Maria, the pre-split takes place between the final wall and the buffer blast line. The ROC L8 drills 6” diameter holes every two metres at an angle of 72 degrees. Miguel Miramontes, Head of Blasting, explains that the charge for pre-splitting is done in a ‘sausage string’ 59

MINERA MARIA'S PRE-SPLIT PIONEER

  Garibay adds: “With diameters of 11–12 inches, the holes drilled by our rotary rigs are far too big for pre-splitting. The smaller the diameter, the better the pre-splitting. Also, it’s very difficult for the rotary rigs to drill at an angle. So having a rig with the capacity to drill such hole diameter, and at that inclination, is a big advantage for us.”   Although currently drilling 6” diameter holes, the ROC L8 has the capacity to drill holes of 41/2-7”, which will also be useful to the mine in the near future as the management is now planning to reduce the diameter to 41/2”. Explains Garibay: “This will allow us to use lower density explosives and by doing so, there will be less damage to the final wall.”   With an average utilization of 24 per cent (which will increase once the machine is employed in the Lucy pit), and productivity of 38 m/h, the ROC L8 has had no problems at Minera Maria.   Says Garibay: “To be completely honest we didn’t expect it to get such good results. We did a cost/benefit analysis before the purchase and we estimated that it would give us a productivity of 34 m/hour. The machine is currently achieving an average of 38 m/h but sometimes we get 48 m/ hour.”   Because of the success attained with the machine, the management at Minera Maria is now keen to experiment with what they call ‘double height bench drilling’. Instead of 15 m benches, 30 m benches would be used.

the rig is sometimes used for production blast drilling, using a vertical drilling pattern of 5.0 m x 6.0 m at a depth of 16.5 m. “In this application we use the ROC L8 specifically in areas that are too small for the rotary rigs,” says Miramontes.   The drill rig will be increasingly used for production drilling once the exploitation of the Lucy pit starts. “Because there are no electric services in the Lucy pit, we have now planned for all the production and presplitting work in this area to be done with the ROC L8 machine,” says Garibay.   The ROC L8 can also be used for sample drilling and there are plans to use the machine in exploration drilling to confirm block models. “This is to be even more certain of our proven ore reserves,” says Miramontes. Atlas Copco’s Ricardo Ornelas explains: “The ROC L8 can perform sampling work through reverse circulation drilling, giving the machine great flexibility in surface operations.”   The management is keen to look after the ROC L8. Says Garibay: “It is an excellent machine and very useful for us.”   The ROC L8 is equipped with a COP 54QHD hammer using Secoroc 6” spherical button bits. Ernesto Romo Villarreal of Atlas Copco Mexicana Technical Services, explains that the first hammer was changed after 22,000 m and the bits are lasting an average of 4,100 m.   Romo assisted with the training of the operators as well as the mine’s mechanics and electrics technicians. Says Garibay: “We thought that the operators were going to find the machine too complicated. It has been the complete opposite.”   This was confirmed by operator Jesus Gavino Rivera, who has been working at Minera Maria for over three years. Interestingly, he has also been an operator of the rotary blast drill rigs. “It was very easy to learn how to operate the ROC L8,” he says. “I’ve had no problems.” Rivera is also very pleased with the machine itself. “By the time I started operating it, it was nearly the end of the year and after working with it I said it was a Christmas present for the mine. The ROC L8 is a great machine, it drills very fast and I’m very happy with it!”

Versatile Rig

Acknowledgements

  The ROC L8 has impressed the mine with its versatility. In addition to pre-splitting,

This article first appeared in Mining & Construction No 2, 2006. ■

fashion, with emulsion of 2” x 16” and with a spacing between each charge of one metre. “In each drill hole we use eight pieces, which weigh 0.96 kg each. We use detonator cord for connecting the charges and an instant fire sequence.”   Minera Maria is particularly pleased with the symmetry of the drilled hole line and the shape of the slopes after blasting with the ROC L8 as this has a good effect on the blast waves as these expand. “Those waves die then and there – they don’t go beyond the established line,” says Miramontes.

Big Advantage “We use the ROC L8 specifically in areas that are too small for the rotary rigs.” Miguel Miramontes, Head of Blasting.

60

Drilling in Open Pit Mining

chile and brazil

ROC L8 Gains Favour in South America Flexibility with Manoeuvrability The ROC L8 drillrig from Atlas Copco is up to 7 t lighter than the rigs it is replacing in the world’s open pit mines, yet its drilling capacity is up to 35% greater. However, perhaps the most important attribute of the ROC L8 is its ability to drill with side inclination, enabling this high efficiency to be applied to both pre-splitting and production work. The lighter weight and better manoeuvrability of this top-of-the-range DTH rig facilitates multitasking, so that a single machine may handle the entire drilling needs of quite large operations. Hence, at the 7 million t/y Saiva quarry in Brazil, one ROC L8 replaced two large rotary rigs, and now drills the whole 7,000 m/month required to subtend full output. A similar story attends the changeover to DTH for pre-splitting at Chuquicamata in Chile, one of the largest open pits in the world. Wherever DTH replaces rotary, the customer benefits from higher productivity and lower costs, with less drillrigs required to do the job.

Pre-Splitting at Chuquicamata Located some 200 km north of Antofagasta, and 2,800 m above sea level in the desert of northern Chile, the Chuquicamata copper mine is the most important of the five divisions in the state-owned Codelco company, the world’s largest copper producer. It is a huge open pit, some 8 km-long, 2.5 km-wide and 750 m-deep, requiring a half-hour drive to get to the bottom. Chuquicamata contributes 180,000 t of the 640,000 t of ore mined by Codelco every day. During 2001, the pit is expected to yield 620,000 t of refined copper and 13,500 t of molybdenum. Mining started at the site 85 years ago, and it is estimated that there are still suffi­ cient reserves for another 25 years of ­production at today’s rate. There are also plans to go underground by 2008. DRILLING IN OPEN PIT MINING

Pre-splitting operations in the open pit have previously been carried out by large and heavy drillrigs. However, big hole blasting and heavy explosive loads result in irregular and unstable benches, which tend to reduce efficiency. In addition, the mine management was aware that, just by increasing the pit slope by one degree, the production of waste rock over the life of the mine could be reduced by a staggering 150 million cu m. In an attempt to relieve this problem, three smaller, more manoeuvrable Atlas Copco ROC L8 rigs have been introduced by drilling contractor Jaime Navarette SA. This specialist in pre-splitting technology is applying the new rigs for 6 in DTH drilling of 18 to 24 m-long holes inclined at 20 degrees. The outstanding drilling accuracy of the rigs, when applied to properlyformulated pre-split patterns, reduces the amount of explosives required to form the pit slope. This minimizes the shock waves reflected into the rock wall, reducing cracking and potential spalling, and resulting in safer benches and more stable slopes. The ROC L8 rigs are also giving the

One of the three Atlas Copco ROC L8 DTH drillrigs at Chuquicamata.

61

ROC L8 gains favour in south america

the site are: weight, 18 t compared to over 25 t; length, 7 m compared to 11-14 m; fuel consumption, 50-55 lit/h compared to 70-75 lit/h; tramming speed, 3.6 km/h compared to 2.5 km/h; and drilling capacity, 100 drill m/h compared to 75-80 drill m/h. An additional bonus is that, unlike the larger rigs, the ROC L8 can also drill with side inclination.

Flexible Production at El Soldado

View of the benches at 750 m-deep Chuquicamata open pit.

Atlas Copco ROC L8 crawlers drilling 250 mm presplit holes at El Morro open pit at El Soldado.

62

mine improved rock fragmentation and better drilling flexibility. They are operating 24 h/day in three shifts, each drilling 12,000 m/month at penetration rates of 35 m/hour, and giving 85% availability. Tests have also been carried out using the 8 in­diameter Secoroc COP 84L DTH hammer. Maintenance of the rigs is the responsibility of Atlas Copco, under a contract involving a 10-person team. A second ­contract covers supply and maintenance of the Secoroc rock tools used in the ­operation. The rig operators were impressed at the rigs’ drilling capacity compared to their larger predecessors. In one month, before delivery of the mine’s third ROC L6, two of the rigs drilled 31,000 m, with a best day of 1,200 m, and an average of 450-500 m per 12 h shift. The minimum drilling output for the two rigs was 22,500 m/month. The characteristics of the ROC L8, compared to the conventional drillrigs used at

El Soldado, run by Anglo American Chile, is a tightly integrated operation consisting of an underground and an open pit copper mine, a concentrator and an oxide plant. The El Morro open pit section of the mine was started in 1989. The property is ­located 132 km north-west of Santiago, Chile, on the western slopes of the Coastal range, at about 830 m asl. In 2002, El Soldado produced 62,800 t of copper in concentrate, and 5,500 t of copper cathode at an average cash cost of 43 US cents per pound. Reserves at El Soldado are esti­mated to be 115 million t grading around 1% copper. Production of 18,000 t/day is split 49% from surface and 51% from underground, where the grade is slightly higher. The current capacity of the ­ sulphide plant is 6.5 million t/y. The El Soldado deposit is located in the Lower Cretaceous Lo Prado formation, and is thought to be of epigenetic origin. The main host rocks are trachytes, followed in importance by andesites and tuffs. Copper mineralization occurs as numerous isolated orebodies, with a strong structural control, located throughout an area 1,800 m-long by 800 m-wide. The main gangue minerals are calcite, quartz, chlorite, epidote and albite. Rock hardness is 150 Mpa. Production from El Morro open pit is 3.5 million t/y of ore, using a bench height of 24 m. Two Atlas Copco ROC L8 rigs are the mainstays of the drilling fleet, ­handling pre-split drilling of 162.5 mm (6.5 in) holes at 1.5 m spacing. Their net penetration rate is 1.2 m/min at 22 bar pressure, and they drill each hole in 35 minutes. It then takes one minute for the ROC L8s to move between set-ups. Because the ROC L8 can drill at an angle, the mine can maintain ideal slope inclinations of 85 degrees in ore and 65 degrees in waste. Pre-splitting produces smaller amounts of large boulders, offers DRILLING IN OPEN PIT MINING

ROC L8 gains favour in south americA

better stability, minimizes slope damage, and reduces global mine cost. The rock drilling tools (RDT) supply contract at El Morro is based on a fixed cost/m, including DTH hammers. Average bit life is 1,500 m; hammer life 8,000 m; and tube life, 6,500 m. The bit grinding service uses a Secoroc Grind Matic BQ2. The differences between the ROC L8 and conventional rigs are: weight 18 t vs 25 t; length 7 m vs 10 m, or more; fuel saving 25% to 30%; and higher drilling capacity 20% to 25%. In addition, at El Morro, the ROC L8 offers easier tramming across rough terrain; needs no hydraulic jacks for stability; and features greater production flexibility. The conventional rotary rigs at El Morro consume 72 lit/h of fuel, whereas the ROC L8s need only 52 lit/h, a saving of 28%. Higher productivity results in the ROC L8s drilling 2,400 m/month more than the conventional rigs. As the El Morro open pit is situated immediately above the underground mine, an integrated mine plan is required, in which the sequence of extraction, both in the open pit and underground, needs to satisfy safety and efficiency criteria. In particular, the design and extraction sequence of underground stopes have to be managed in such a way that they do not affect the open pit operations, and minimize disturbance to unmined areas, enabling maximum resource recovery. It is also essential that the surface rigs have mobility and dependability, in order to switch quickly between drilling areas, as dictated by the mine plan.

Limestone for Rio Branco The Saivá quarry in Brazil is another operation to benefit from the introduction of the ROC L8. It is one of several open pits which supply the Cimento Rio Branco cement factory with limestone from sites in the southern part of the country, near the small city of Rio Branco do Sul in the state of Paraná. The mine belongs to the Votorantim Group, the largest cement producer in the region. Saivá recently replaced two large rotary drillrigs with a new ROC L8 drillrig from Atlas Copco, and found that it was able to cut costs while sustaining productivity. The comparison between the performances of the two rotary rigs and the new DTH drillrig demonstrates that the Atlas Copco equipment has a huge advantage. DRILLING IN OPEN PIT MINING

Initially, it was not believed that a comparatively light machine like the ROC L8 could produce such high performance. However, its drilling capability has been proved in practice, and the machine now supplies the whole Saivá quarry output of 7 million t/year. The Saivá quarry formerly drilled 6.5 indiameter (165 mm) holes, but now, with the new ROC L8, 5.5 in-diameter (140 mm) holes are sufficient, yielding a 6% reduction in the consumption of ­explosives. The rig is equipped with a COP 54 QHD down-the-hole hammer, having an average life of 12,000 drill metres. The 5.5 in-diameter ballistic bits, which last for some 5,000 m, are supplied by Secoroc. The ROC L8 works two 8 h shifts/day, 300 days/year, drilling a 4.8 m x 8.0 m ­pattern. The benches are 15 m-high, and the drill holes are 15.5 m-deep. Hole inclination is 15 degrees. Some 7,000 m are drilled each month. Quarry data shows that the original drilling cost/m has been reduced by 46% for the ROC L8. Productivity has increased by 100%, accompanied by a large annual cost reduction. Atlas Copco is providing labour, spare parts and drilling consumables, which include the DTH hammer, under the terms of a cost/metre contract. The customer is extremely pleased with the continuous after-sales service, and plans to extend the system to other quarries in the group. Atlas Copco’s positive attitude in helping to solve problems has created an innovative partnership. Votorantim has since purchased a second ROC L8 unit to use in

Atlas Copco ROC L8 doubled productivity at Saivá quarry.

63

ROC L8 gains favour in south america

another quarry in the state of Sao Paulo, and a ROC L6 for limestone production at Cimento Tocantins, Sobradinho, in Goias State.

Powerful Specification

Straight holes give better slope stability.

Atlas Copco’s ROC L8 is a high production down-the-hole crawler with ample power to deliver high penetration rates and deep holes. It has a rod handling capacity for hole depths of 54 m (176 ft). The great advantage of the ROC L8 is that it can be used for both pre-splitting and production, making it a total solution for drilling in quarries and open pit mines. The ergonomically designed ROC L8 cab, with its superb all-round visibility and user-friendly layout, reduces operator fatigue to a minimum, and increases safety to the maximum. The seat is fully adjustable, and the cab meets all international safety requirements. The ROC L8 is equipped with a high performance down-the-hole hammer for fast and straight drilling. As an option, a back hammer system can be added to take care of stuck drill tubes. The ROC L8 also features a hydraulic break-out table and double drilltube support, which helps the operator thread and unthread drilltubes, saves on drilltubes consumption, and helps drill straighter holes. The feed and the rotation unit are mounted on a flexible, single-section boom with a ±30 degrees wide feed swing to right and left, and forwards. The drillrig is powered by a 317 kW

(431 hp) Caterpillar diesel engine, with sufficient power for normal drilling and tramming. It therefore lasts longer, is low on fuel consumption, and has more than enough power for fast drilling in the most demanding rock.

Straight Holes An onboard Atlas Copco 405 l/s (858 cfm) screw compressor delivers up to 25 bar of air pressure for extra-high penetration and strong flushing, giving straight clean holes that are easy to charge. This unit is well up to the task of delivering top performance, even when drilling holes as large as 165 mm (6.5 in) down to depths of 54 m (176 ft), and flushing them clean for ­charging. An electronic system for hole inclination and depth control ensures that blastholes are perfectly aligned. The machine is mounted on heavy-duty tracks with 18 degrees (–8 degrees/+10 degrees) of oscillation, for excellent tramming and site manoeuvrability. The ROC L8 can be fitted with a range of Atlas Copco down-the-hole hammers such as COP 44, 54 and 64 (4 in, 5 in and 6 in). These are among the fastest on the market. Their high performance, together with great functional reliability and outstanding service life, gives first-class drilling econ­ omy. The superior penetration rate of these DTH hammers is due to a more efficient impact mechanism, and better use of compressed air energy. Flexible suspension of the central control tube enables the piston to be manufactured with much closer tolerances. This minimizes internal air leakage, and optimizes the transmission of energy. Two important benefits result: a higher penetration rate, and lower fuel consumption per metre drilled.

Acknowledgements Atlas Copco is grateful to its clients in Chile and Brazil for their contributions to this article, which first appeared in Atlas Copco Surface Drilling, First Edition, published in 2002. ■

64

DRILLING IN OPEN PIT MINING

Atacama, Chile

Hydraulic Tophammers Exceed Soquimich Expectations Long Service Contract for Drillrigs As the world’s sole producer of nat­ ural nitrates, and one of the largest producers of mineral salts, Sociedad Quimica y Minera de Chile (Soquimich) has to be competitive in order to maintain its position. Somich, the company’s operating subsidiary, has four mines and seven processing plants in the Atacama Desert region of northern Chile, located between the coastal cities of Iquique and Antofagasta. The first mine, El Toco, com­ menced production in 1927, and the latest, Nueva Victoria, came on stream in 1996. Despite consistently high output over the years, reserves are estimated as sufficient for another 50 years. Some 58 wagon drills were required to satisfy production demands in the early years of operation. By 1981, for an output of 15.5 million t/y, Somich had reduced this number to 23 units, of which five were Atlas Copco ROC 302 pneumatics. Nowadays, just seven Atlas Copco ROC F7 crawlers are employed to produce 18 million t/y. The switch from pneu­ matic to hydraulic pro­duction drilling equipment has brought other benefits, not least of which is more com­ fort for the operators. Soquimich has signed a five-year service and main­ tenance contract with Atlas Copco, which allows the company to main­ tain a constant level of drilling costs over long periods.

assets of the Chilean state-owned development organi­zation Corfo and the ­ private company Anglo Lautaro. Soquimich was subsequently floated on the Santiago stock exchange, and, by 1988, the company was entirely in pri­vate hands.

One of seven Atlas Copco ROC F7 rigs working in the Atacama desert.

nueva victoria

el toco

Natural Nitrates Sodium and potassium nitrate are used as basic ingredients for fer­tilizer manufacture and as preservatives. The nitrate deposits occur within a 700 km-long belt located some 15 to 60 km from the Pacific coast of northern Chile, in the Atacama Desert. For the last 15 million years, this has been one of the driest regions in the world. In the 1830s, Chile began supplying much of the world’s commercial nitrate requirements from these deposits. Soquimich was established in 1968, and took over the nitrate DRILLING IN OPEN PIT MINING

Pampa blanca

Location map showing Somich installations in Chile.

65

Hydraulic Tophammers Exceed Soquimich Expectations

sodium sulphate; 600,000 t potassium ­chloride; 250,000 t potassium sulphate; 16,000 t boric acid; and 20,000 t lithium carbonate.

Drilling Capacity

Two graphs show the progressive increase in Somich drilling capacity with the introduction of new technology over the past 22 years.

Since then, the Chilean nitrate industry has been modernized by the addition of better processing facilities and improved mining equipment.

Mine Production Soquimich employs 800 direct workers and 300 contract operatives on its four mines. The mines are: Pedro de Valdivia, which started operations in 1931 and produces 12 million t/y of crude nitrate; El Toco, start­ed in 1927 and producing 6 million t/y; Pampa Blanca, started in 1995 and alternately producing 5.0 million t/y; and Nueva Victoria started in 1996 and producing 5 million t/y. The crude nitrate ore is conventionally mined in open pits by drilling and blast­ ing, and is hauled by trucks to the crushing plants, where it is reduced to 12 mm ­no minal sizing. Some 70% of the product is then leached in shallow pans to recov­er nitra tes, iodine, sulphates and other salts. The remainder is transferred to leaching stacks. Each mine has its own production plant, and Soquimich has a further two plant ­facilities at Coya Sur and Salar de Atacama. The collective output of the plants is 980,000 t saltpetre; 6,500 t iodine; 60,000 t 66

In 1983, the remaining 18 wagon drills at the mines were replaced by another five Atlas Copco ROC 302 rigs. With the demise of pneumatic machines for mainstream production, the 302s were replaced in 1992 by seven hydraulic Zoomtrack 600 crawler drills, and these, in turn, were replaced with the seven current generation high capacity Atlas Copco ROC F7 rigs. Atlas Copco offers a choice of Caterpillar or Mercedes diesel engines to power its ROC F7s. Those at Somich are equipped with Mercedes engines delivering 170 kW. They also feature the powerful COP 1838 rock drill, which returns an average 65 drill m per diesel engine hour, or over 100 drill m/h, using 76 and 89 mm ballistic bits and T45 rods. The mine management confirms an increased mineral production performance, compared with the previous generation crawler rigs. Performance is 20% better, and the number of effective operational hours has increased by 5%. With a drilling rate of production now running at 450‑m/ shift, three shifts/day, Somich is able to keep one rig on standby, and still meet the demanding targets. In order to stabilize the holes for charging, water mist flushing has been introduced to replace the previous air flushing system on the ­drillrigs. Atlas Copco provided training for the drillrig operators on the advanced ROC F7, and taught Somich fitters how to maintain the Mercedes engine. Drillrig availability is over 90%, a level which the mine accepts as very satisfac­ tory. The ROC F7 drillrigs were accom­ panied by a five-year mainten ance and repair ­contract, under which Atlas Copco is responsible for all ­maintenance.

Acknowledgements This article first appeared in Atlas Copco Surface Drilling, First Edition, published in 2002. ■

DRILLING IN OPEN PIT MINING

iquique, chile

Winning Iodine from the Atacama Desert World’s Largest Located in the Atacama Desert region of Northern Chile, near the city of Iquique, DSM Minera S.C.M (Sociedad Contractual Minera) oper­ates what is claimed to be the world’s largest iodine production facility, processing over 400,000 t/month of ore. Here, two Atlas Copco ROC D7 hydraulic drillrigs, some of the first units of this type in South America, are being employed by contractor HIT as the main ­production drilling equipment.

Key Industry DSM Minera S.C.M. is one of the business units of DSM Fine Chemicals, which in turn is owned by DSM, the Dutch producer of special­ity chemicals. Ironically, the name DSM origi­nally stood for Dutch State Mines, a coal mining company founded by the Dutch gov­ernment in 1902. DSM first became involved in DSM Minera in 1991, when it acquired a 30% interest. The remaining 70% of the operating company was acquired in 1997, and in 1999 DSM installed its own management team. Present reserves stand at 7-10 years, although this figure is expected to increase, as the company owns mining rights in nearby areas, which still have to be ­developed. DSM Minera’s main activity is the produc­tion of iodine, which is used as a feedstock in the manufacture of iodine derivatives for a diverse range of applications, including disinfectants, agrochemicals, food and feed additives, heat stabilizers, and for X-ray diagnostic ­purposes. The global market for iodine is around 19,000 t/y. Chile is by far the largest producer, where it is normally extracted as a by-product or co-product associated with nat­ural nitrates. These days, the Chilean nitrate mining industry is relatively small, though in its heyday, more than a century ago, it com­pletely dominated the fertilizer DRILLING IN OPEN PIT MINING

industry, and vast fortunes were made. The remains of many of these old mines are still to be found, preserved in the dry desert air.

HIT has two ROC D7 drillrigs.

Effective Process The production process at DSM Minera is simple, consisting basically of drilling, blast­ing and leaching operations. The first part of this process, drilling and blasting, is carried out by Chilean contractor HIT, under a five-year contract signed with DSM Minera. Blasting, mainly with ANFO, is carried

Blowing out holes ready for charging.

67

Winning Iodine from the Atacama Desert

The ROC D7s drill out a “mancha” ready for blasting.

out to prepare the material located in each ‘mancha’, the Chilean name for the designated area to be drilled and blasted. Once HIT has drilled and blasted, the material is leached in-situ, draining to lower areas through pipes to specially-made canals leading to the recovery plants. This has been a very cost-effective method, in which the ore is irrigated with water for 6-8 months to produce Iodate solution. Within the plants, which are ISO 9002-certified facilities, a series of chemical processes are applied to the solution to obtain high purity iodine. DSM uses 40% of this iodine to make derivatives, and the rest is sold into international markets. DSM Minera operates several process plants, with a combined output of over 2,000 t/y of iodine. An additional new plant, with an output of 600 to 1,000 t/y, was recently com­missioned, facilitating an increased ore throughput from the current 400,000 to 700,000 t/month.

Tough Drilling The contract between DSM Minera and HIT specified 400,000 t/month of ore, for which the contractor had to drill 50,000 m/ month of rock. In order to satisfy this objective, HIT acquired two Atlas Copco ROC D7 tophammer hydraulic drillrigs. HIT, which is a family company run by father and son, Hernán Iribarren Torres, general manager and Alejandro Iribarren, operations manager, respectively, has been operat-ing for five years, and has a workforce of 22 people. The com­pany already had two ROC 203 pneumatic rigs, which it used 68

for secondary drilling on other contracts. This equipment was not powerful enough for primary drilling work, so the company decided to invest in new hydraulic rigs. The ROC D7 machine is one of the newest models in the Atlas Copco series of tophammer rigs, and the units employed at DSM Minera are some of the first of this type working in South America. Apart from Chile, the ROC D7 is also working in Mexico and Brazil. With a hole diameter range of 35-102 mm, the ROC D7 rig features a powerful engine, good flushing capacity and flexible booms with extra long reach. The machine comes with a COP 1800-series rock drill with a maximum impact power of 20 kW, a fuel-efficient Caterpillar engine delivering 149 kW, and an Atlas Copco screw type compres­sor with a working pressure of 10.5 bar (152 psi). In addition to the HIT ROC D7, Atlas Copco ROC L8DTH and F7 tophammer crawler drillrigs are operating in north Chile. The hydraulic winch on the ROC D7 makes drilling a lot easier in the rough terrain of the Atacama Desert, as it has more power and strength. One-man operation is also a major bonus on these new generation machines, which offer many advantages in capability and mobility. By increas­ing the drilling diameter from 63 mm to 76 mm, HIT has been able to eliminate 168 holes, or 437 m of drilling, to obtain the same ton­nage/month. Also, by changing the grid pattern, the explosive was found to perform more efficiently. The ROC D7 rigs are drilling between 60 and 70 m/h on each shift, with an availability of around 85%, while the operators familiarize themselves with the rigs. Atlas Copco Chilena has been instrumental in training the rig operators, using a full time technician. The company also has a maintenance contract with HIT, and supplies the Secoroc drill steel. HIT has taken delivery of a third ROC D7 unit to support DSM Minera’s plans to increase ore throughput to 700,000 t/month.

Acknowledgements Atlas Copco is grateful to DSM Minera and contractor HIT for their help and assistance in the production of this article which first appeared in Atlas Copco Surface Drilling, Second Edition, published in 2004. ■

DRILLING IN OPEN PIT MINING

shuichang, china

Replacing Rotary in Iron Ore Small is Beautiful The large Shuichang open pit iron ore mine is located near the Luan River, about 200 km east of the Chinese capital, Beijing. It is one of the major sources of raw materials for the Capital Iron & Steel Company, and was once the largest open iron mine in Asia, with an annual output around 15 million t of ore, and 45 million t waste stripped. Shuichang is a subsidiary of the Mining Company of Shougang Corporation, and is a state-owned enterprise. For some 30 years, large rotary rigs had formed the main drillrig fleet, when two Atlas Copco ROC F9 crawlers were introduced. To the great surprise of the local operators, they outperformed the rotary rigs, resolving presplitting problems in the very weathered rock, while creating a much safer loading and hauling ­environment.

Geology and Operations Shuichang started operation in the early 1970s, mining magnetite as the primary mineral in the ore, with martite as a secondary product. The natural ore deposit is composed of four constituents: magneti-tic quartzite, pyroxene-magnetitic quartzite, magnetitic pyroxenolite and hematitic quartzite. Mineral size in the ore is usually 0.0620.5 mm, with a moisture content generally between 0.10% and 0.20%, averaging 0.143%. The average porosity of the ore is 4.08%, and its average weight/unit volume is about 3.24 t/cu m. Shuichang Iron Mine is rated as a lowgrade iron deposit. The average geologic grade is 26.71%, and the average iron silicate content in the ore is 1.73%. From these data, the Fe grade is calculated to be about 28.44%. Geologic grade varies greatly with depth. The main associated gangue minerals are quartz and mussite, with hypersthene, hornblende, garnet and black mica as ­ secondary constituents. More than ten rotary drilling units have been used from time to time for presplitting and production work. The bench height is about 12 m, and the hole diameter drilled by the rotary rigs is about 310 mm. DRILLING IN OPEN PIT MINING

Two ROC F9-11 folding boom crawler rigs were delivered to the jobsite in November, 2002. These were equipped for drilling 115 mm holes to nearly 30 m depth.   At first sight, the mine staff had great difficulty in accepting that the ROC F9-11, which is physically a much smaller rig than the equivalent rotary machine, would be a suitable replacement. However, the new rigs soon proved their worth and, after six months operation, the customer was very satisfied with their flexibility and performance. The operators are very happy with the ergonomic layout of the cab, finding it comfortable, and making it easy for them to operate the rig. The management has expressed satisfaction with the high penetration rate, and the output of almost 400 m/day. They have also found the rigs to be very flexible, drilling at all angles to meet their presplit requirements. The dieseline consumption is also much lower than expected, leading to better overall costs. As a result, the company has taken delivery of a further two Atlas Copco ROC F9 rigs, and another five iron ore producers in the region have expressed interest in buying this type of rig in the near future.

Atlas Copco ROC F9 crawler rig, one of four working at Shuichang iron ore mine.

Acknowledgements This article first appeared in Mining & Construction No 2, 2003. ■ 69

kimberley and laverton, australia

Multiple Tasking in Western Australia

Drilling cablebolt holes at Argyle.

Diamonds and Gold According to official statistics, the annual export value of minerals and metals accounts for nearly 30% of the total exports of goods and ­ services from Australia. The remote Kimberley region of Western Australia makes a valuable contribution, with diamonds and gold high on the list, from open pit mines that have some of the toughest working conditions on earth.   In such difficult locations, the client places more reliance on manufacturers, not just to supply the most flexible, robust and reliable equipment, but to assist in commissioning, training, ongoing maintenance, and the resolution of any abnormal parts and service problems that may occur. Atlas Copco engineers and fitters regularly visit each mine, and the client can call them for advice at any time. They have demonstrated a high degree of product and industry knowledge, and are proving to be a valuable source of information, keeping the clients up to date on product developments. Access to such relevant expertise helps keep the machines working at their very best.

Rock Engineering at Argyle Australian company Rock Engineering specializes in the contract supply and installa tion of ground support products in 70

underground and open pit mines and civil construction applications, and is one of the first to offer this service. Rock Engineering has a large portfolio of projects, both in Australia and overseas. These include the ground support programme at the Argyle Diamond Mine, located 130 km south of Kununurra, in the isolated Kimberley region of Western Australia. The Rock Engineering fleet on site was strengthened by the addition of an Atlas Copco ROC F9 surface drillrig in May, 2002. As the first Atlas Copco machine to be used by the company, there was great interest in its performance! The Argyle mine was commissioned in 1985, following a long period of exploration that initially commenced in the Kimberley more than a decade earlier, in 1972. It now produces more diamonds than any other mine in the world, and is renowned for being the only source of the rare and valuable pink diamond. For what is now a large open pit mine, Argyle has relied on Rock Engineering to provide ground support and pre-splitting of the final walls for nearly four years. Currently eighteen months into the twoyear second phase of the ground support fixed-price contract, Rock Engineering has been on site for around three years in total, having completed Phase One prior to the current contract. Mine life for the open pit is predicted for another four years, with the potential to commence underground operations after that time. To perform its work on site, Rock Engineering owns and operates a fleet of underground and surface equipment.

Rugged and Reliable The ROC F9, along with all of the machines in the Atlas Copco Open Pit Series, has been designed for rugged conditions, with enough strength and flexibil­ity to handle the most demanding tasks. Thanks to its folding boom, the ROC F9 boasts the longest vertical and horizontal reach of any similar machine. It is also equipped with the most powerful top­hammer in its class. DRILLING IN OPEN PIT MINING

Multiple Tasking in Western Australia

The rig is powered by a 231 kW engine and an Atlas Copco screw compressor delivering 188 lit/sec. The design facilitates more holes per rig set-up, because less time is spent tramming, making more time available for drilling. Rock Engineering’s decision to purchase the ROC F9 was based heavily on its versatility, because the folding boom is suitable for both drilling cablebolt holes, and for pre-splitting. At Argyle, cablebolt holes are drilled at 89 mm-diameter to a depth of 23 m, while pre-splitting is carried out to a depth of 25 m. As well as these two main functions, the machine is also occasionally used for drilling blastholes, and pit holes for dewatering. The company appreciates this versatility, but has also found that the ROC F9 outperforms its predecessor on all functions. This is partly credited to the angling capability of the drillrig’s mast, which allows the operator to insert bolts quickly, and with minimal manoeuvring of the unit. The operators are also able to see all of the rods from the cab, which they report has led to more efficient drilling.

Good Company The ROC F9 drillrig is used at Argyle on a 10 h shift basis and, even in the site’s variable rock conditions, is meeting all requirements placed upon it. It was recently joined by a ROC L8, another machine from the current Atlas Copco series, which arrived on site during May, 2003. This latest addition is being used to drill 150 m-long dewatering holes at a 5-degree upward angle, and 200 m-deep vertical holes, although it is also capable of pre-split and production drilling. The rig uses a 5 in hammer, 89 mm drill pipes, and 140 mm bits, and the carousel has been modified to allow for re-load of pipes every 48 m. The Australian drilling contractor market has a reputation of being one of the most demanding in the world, with some of the toughest working conditions. In summertime, the operators face ambient temperatures above 55 degrees C in the pits. The rock stores the heat, and radiates it at night. The Atlas Copco rigs have been customized to handle these sorts of conditions, together with the contractors’ specific needs.   Widened application range, exception­ally low running cost, and enhanced reliability are the main reasons for the rapid acceptance of the ROC L8 in Australia. DRILLING IN OPEN PIT MINING

Fitted with a Caterpillar C12 317 kW engine, the ROC L8 provides powerful down-the-hole drilling with COP 44, 54 and 64 Gold hammers, which are among the fastest on the market. Combining manoeuvrability, strength and precision, the rig can drill accurately throughout a large range of angles. An optional electronic inclination instrument and depth controller ensures perfectly aligned and orientated holes to a preset depth. Heavy-duty tracks, a fuel-saving device, and a dust collector and pre-separator are among the many standard features of the unit. Many other options are available, including an electronic refuelling pump, engine pre-heater, and hydraulic support leg. The ROC L8 was purchased on its own merits, but Rock Engineering experience with the ROC F9 obviously had some influence on their decision. The ROC F9 has reported very few of the teething problems normally associated with the commissioning of a new machine, and achieves 90% availability.

Atlas Copco’s ROC L8 at work at Sunrise Dam open pit.

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Multiple Tasking in Western Australia

Air conditioned cab is essential at Sunrise Dam.

Multiple Tasking at Sunrise Dam The Sunrise Dam gold mine, located 50 km south of Laverton, Western Australia, has been operational since 1997. It has gone through numerous upgrades and expansions, and the open pit has now reached a depth of 460 m. Since 2000, conventional open pit mining has been carried out by Roche Mining, the mining division of Downer EDI, one of Australia’s major providers of mining services, and winner of the inaugural Gold Industry Supplier of the Year in 2003. Roche Mining introduced the new Atlas Copco ROC L8 crawler in November, 2002 to help rescue the steadily declining output. In early 2002, approximately 1.4-1.6 million bank cubic metres were mined per month, an output already declining with increasing pit depth and decreasing strip ratio. To obtain this output, Roche Mining operates a range of large trucks, excavators and drillrigs. Traditionally, separate machines have been required to perform the various drilling functions, particularly grade control drilling, where normal production rigs were unsuitable because of the requirement to blow air back up the drilltube. However, the revolutionary Atlas Copco ROC L8 DTH rig is designed to handle

72

reverse-circulation grade control, pre-split, and production drilling. With this in mind, Roche Mining took delivery of a new ROC L8 towards the end of 2002, proposing fast changeover times to enable their operators to fully utilize the multiple functions of the rig, without compromising on performance. The ROC L8, powered by a robust Cat 317 kW (430 hp) diesel engine, is compat­ ible with some of the fastest DTH rock drills on the market, including the COP 44, 54 and 64. Heavy-duty tracks with 18 degrees of oscillation, low centre of gravity, good weight distribution, and good ground clearance all contribute to the impressive terrain and tramming abilities of the ROC L8. During 2003, the ROC L8 is easily meeting the target figures, while satisfying initial expectations, and is achieving drilling rates equivalent to the outputs of Roche’s larger machines. The machine currently performs reverse circulation, blasthole and pre-split drilling, a flexibility of operation that is praised by the owner. A fast changeover time ensures that the multiple functions of the rig are used efficiently, and there is no compromise on performance.

Versatile Asset The ROC L8 at Sunrise Dam has proved to be a versatile asset that is meeting all requirements, and is building a reputation as a well-designed machine that facilitates multifunctional use in mining. During the first two months of operation, an Atlas Copco technician attended site full time, to ensure that everybody was at ease with the new arrival, and confident with its functions and use. Roche Mining now receives a weekly visit, to ensure that everything is working at its best. Based on the machine’s merits alone, the company is looking forward to including more units into its fleet in the near future.

Acknowledgements Atlas Copco is grateful to the management and contractors at Argyle and Sunrise mines for their inputs to this article, which first appeared in Atlas Copco Surface Drilling, Second Edition, published in 2004. ■

DRILLING IN OPEN PIT MINING

POSTMASBURG, SOUTH AFRICA

ROC L8 Outperforms in Assmang Iron Ore Testing Conditions Wherever the Atlas Copco ROC L8 DTH drill rig has been introduced, it has quickly earned a reputation for independence and flexibility. Capable of drilling large-diameter holes to great depth, the story has been the same in all applications: more holes for less money. At Assmang iron ore mine at Postmasburg in South Africa, a 250% increase in drilling output was registered by the ROC L8 under test conditions, and its new owners were so delighted with its performance that they ordered three more. Built-in reliability, combined with Atlas Copco service and spares support, is ensuring that this new generation of drill rigs is recording high levels of availability, even when drilling around the clock in remote situations.

Winning at Assmang When drilling contractor Booysen Bore secured a contract at Assmang, a mine with an iron content of 65% and a strength of 650 MPa, they purchased an Atlas Copco ROC L8.   The penetration rates and production capabilities of the ROC L8 quickly became apparent, causing Booysen Bore to order three more similar machines to replace their ageing fleet of waterwell rigs.   At Assmang, 165 mm holes are being drilled in bench heights varying from 8-13 m, and in different grades of ore. Bits need to be sharpened every metre when drilling into the top grade of iron ore, and every 6 m when drilling into waste. The ore:waste ratio in the pit is 80:20. Nevertheless, the ROC L8s, which are predominantly used for production drilling and some minor secondary drilling, are each achieving a net penetration of 33.8 m/h, with an overall average of 19 m/h for the four rigs.

Contractor’s Dream Booysen Bore drills 43,000 m/month, on a 24 h/day, 5 day/week cycle. Their ROC L8 rigs are equipped with 6 m-long tubes, Drilling in Open Pit Mining

so that most holes can be drilled with just two tubes, reducing the number of joints in the drill string and keeping tube changing to the bare minimum. Faster drilling rates and less tube changing means they require 60% less manpower to get the job done. The drillers are finding the rigs easier to operate than the old fleet, and really appreciate the comfortable cabin on cold nights.   The ROC L8 is versatile, with boom movements that are able to drill 30 degrees left and right for pre-splitting, and forward, if necessary. The onboard depth and inclination meter is a contractor’s dream for recording metres drilled. The rig is also equipped with an EMS that measures engine speed, temperatures, coolant levels, battery voltage and other useful information.   The company is very happy with the after sales service, consignment stock and training programme, all of which have assured 85% mechanical availability.

Three ROC L8s presplit drilling at Assmang, South Africa.

Acknowledgements Atlas Copco is grateful to Booysen Bore and the owners of Assmang Mine for assistance in the production of this article, which first appeared in Atlas Copco Surface Drilling, Second Edition, published in 2004. ■ 73

tANZANIA, gEITA GOLD MINE

Greater Geita Impressive performance The largest fleet of ROC L8 drill rigs anywhere in the world is hard at work in Tanzania at the Geita Gold Mine, one of Africa’s largest open pit gold operations. An astonishing 14 of these machines are employed in blast hole drilling while two other units, rented by the exploration contractor, are used in reverse circulation drilling. Being extremely flexible and reliable, particularly in adverse weather and rock conditions, this is yet another example of the ROC L8 Down-The-Hole crawler’s high success around the world.    And the Atlas Copco presence at Geita doesn’t stop there: Four CS1000 rigs complement the exploration drilling fleet and two Drilling Solutions DML rigs for large blast hole drilling will arrive shortly at the mine.

Gold Production Located in north central Tanzania, 1,200 km by road from Dar es Salaam, Geita Gold Mining Limited (GGML) is owned by giant miner AngloGold Ashanti. With an impressive production of 24 t/y of gold, Geita is the largest of AngloGold Ashanti’s 11 open pit gold mines, eight of which are located in Africa.    Since its inauguration in August 2000, Geita has shown an impressive performance, greatly exceeding expectations. The mine’s gold production record so far has been: • 176,836 oz in 2000 • 545,561 oz in 2001 • 570,043 oz in 2002 • 661,000 oz in 2003 • 692,000 oz in 2004

   Today these figures have increased to 8.4 Moz reserve with an average grade of 4.28 g/t, 12.7 Moz resource with a grade of 4.46 g/t, a 16 year life and a 6.3 Mt/y capacity plant.

Geita Gold Mine is the largest of AngloGold Ashanti´s 11 open pit gold mines.

Mining at Geita Mining operations at Geita (which has an ISO 14001 environmental certification and a NOSA 4 star safety certification), involves the stripping of over 20 million m3 of rock, using standard open pit mining methods, with drill and blast followed by hydraulic excavators loading into 100 t trucks. The first ROC L8 rig arrived at Geita December 2001. Some of the machines have now clocked up over 15, 000 hours of drilling but still work an average of 21 hours per 24 hours of work.

Geita has a forecast for well over 600,000 oz in 2005. This represents almost half of Tanzania’s annual gold production. Geita Gold Mine now contributes about 6% of the national GDP.    This growth pattern is also reflected in the company’s reserve base. When commissioned, Geita had a 4 Moz reserve, a 7 Moz resource, a 10 year life and a plant capacity of 4 Mt/y. 74

Drilling in open pit mining

tANZANIA, gEITA GOLD MINE

ROC L8´s at some cleaning up work of boulders from an old ramp.

Mr Gathuru Mburu is Atlas Copco´s Branch Manager in Tanzania.

Drilling in open pit mining

Production comes from several open pits; the Nyankanga pit (the largest and where about 30% of the pit production is sourced from, with an output of over 900,000 BCM’s (bank cubic metre) a month; Geita Hill (an interesting challenge as the area being mined is located above a network of old underground workings), Lone Cone (North, Central and South), Kukuluma and Matandani. Future pits to be mined are Chipaka, Area 3 West, Roberts, Ridge 8 and Star & Comet. The latter three pits will go into production in 2008 and will be located about 30 km from the processing plant.   The mining operation is vast and complex, with roads and other infrastructure, including a dam, waste dump, tailings dam, airstrip and numerous buildings spread over a large area.    In a change of strategic direction, from August 2005, AngloGold Ashanti has taken over direct responsibility for the mining operations at Geita, which were previously supplied by a contracting company.    Mr Ettiene Smuts is responsible for the mining department, where a team of mining engineers, supervisors, surveyors, mine geologists and other assistants work together to define the gold bearing ore, design and schedule the pits and waste dumps, and then mark out this information in the field.

   The fleet of drilling equipment comprises 14 Atlas Copco ROC L8 Down-TheHole drill rigs all of which are used for blast hole drilling. Blasting, using ANFO and emulsion, takes place every day. Most of the drill rigs are employed in the large Nyankanga pit and moved to the other working areas as and when needed.    GGM has ordered two Atlas Copco Drilling Solutions DML rigs which will be delivered at the end of 2005. These units will be used for large blast hole drilling in the Nyakanga pit as the cuts get back further, requiring more material to be removed.    Blasthole diameter is 130 mm but the drill pattern varies from pit to pit depending on the ground conditions and hardness. Current drilling patterns used are: • 4 m x 4.5 m x 10 m bench with a sub drill of 1 m • 4 m x 5 m x 10 m bench with a sub drill of 1 m • 5 m x 5 m x 6 m bench with a sub drill of 5 m in the softer areas.    The first ROC L8 rigs arrived at Geita in December 2001. As temperatures can get very high in this part of the country, the machines’ cooling system was modified with an extra cooler in order for the rigs to achieve optimum performance in the severe heat. 75

tANZANIA, gEITA GOLD MINE

Some of the machines have now clocked up over 15,000 hours of drilling but still work an average of 21 hours per 24 hours of work. Thanks to the Down-The-Hole method, these rigs are particularly good when drilling in the water areas around the pits. This method also helps keep the drill consumables cost to a minimum. The high air pressure delivered by the ROC L8s improves air flushing and consequently the penetration rate.    This large fleet of equipment needs constant back-up and technical support, mainly when considering that the machines are working in a remote area where one of the major problems is logistics. In conjunction with the engineering manager, Errol Drake, Atlas Copco Eastern Africa is further optimising the supply and stocking of parts and consumables. There is also a rebuild programme planned for the coming months with major components on the older rigs being replaced. Geita’s Purchasing Managers K. B. Wilson and Simon Dominic say: Because of logistics, supply can be a problem. However, unlike with other manufacturers, we do not have supply problems with Atlas Copco. The company’s local support is very good.”    A high emphasis is placed on machine availability and now that technical support is being provided directly by Atlas Copco 76

Eastern Africa, a new target has been set to increase the rigs’ average mechanical availability to well over 80% in the next 18 months. In order to reach the high monthly targets and keep a strong connection with the drilling team, Atlas Copco Eastern Africa is now responsible for training the personnel in the maintenance and drilling division.

Blasting notification at the Geita Airstrip.

Stanley Mining Services Stanley Mining Services, part of US-based Layne Christensen - one of the largest exploration drilling companies in the world

A high emphasis is placed on machine availability and the technical support is being provided directly by Atlas Copco Eastern Africa

Drilling in open pit mining

tANZANIA, gEITA GOLD MINE

Gold bullion processing.

AngloGold Ashanti continue to invest in new equipment.

- is responsible for exploration and grade control drilling at Geita.    Stanley has operated in Africa for nearly 10 years and apart from Tanzania, it has offices in Ghana, Guinea, Mali and Zambia. Geita mine was the location of the company’s first drilling programme in Tanzania, where difficult ground conditions make the work particularly challenging.    GGM awarded Stanley a contract starting in June 2001. One of their largest contracts, in terms of the work carried out – exploration and grade control - equipment deployed and number of people.    At Geita, Stanley has a workforce of 115 people and has its own facilities, including a workshop, store, training room and a large fleet of equipment on site. This fleet includes four Atlas Copco CS1000, skid mounted rigs and two Atlas Copco ROC L8 rigs. The ROC L8s are on rental from Atlas Copco Eastern Africa.   Stanley’s fleet in Tanzania comprises 15 Atlas Copco Christensen surface core drilling rigs (model CS 1500, CS 3000 and CS 4000 using Craelius diamond bits and Craelius reaming shells), 10 RC drilling rigs and a number of Atlas Copco compressors.    Stanley’s ROC L8 RC rigs are allocated to grade control drilling in the pits. They are fitted with RC drill rods and face sampling Down-The-Hole hammers. For grade control (which is undertaken every 20 m), the machines drill 11 m holes at 60° angle. The choice of ROC L8 was influenced by the fact that the mine already had a large fleet of these machines. Atlas Copco has a team of service engineers on site to provide 24-hour support to Geita’s and Stanley’s fleet of ROC L8 rigs.    With a 2005 budget of US$5.6 million, exploration at Geita is carried out to generate replacement resources at an equivalent rate to which they are depleted by mining operations. The core drilling rigs are used

Mr Greg Kelly is the Drill & Blast Superintendent at Geita Gold Mines

for exploration (core samples) in the field and the RC equipment is used both for exploration in the field and for grade control in the pit. Based on the outcome of the exploration with the RC rigs, the diamond rigs can be deployed to obtain an exact replication of the ground conditions with a solid core sample. This information is given to the mine for the modelling. Diamond drill holes are normally between 300 and 500 m.

Atlas Copco Eastern Africa With a presence in Nairobi, Kenya since 1936, Atlas Copco has its own sales, logistics and aftermarket support customer centre in this country. This centre is also the Group’s Regional Headquarters for East Africa, covering Tanzania, Uganda, Ethiopia, Eritrea, Sudan, Mauritius, Madagascar, Somalia and Djibouti. These markets are supported via a group of skilled sales, logistics and service personnel, trained at factory level to market and service all of the Atlas Copco products and support the distribution network.    In order to extend its service to customers, a new Atlas Copco branch was established in January 2003 in Mwanza, Tanzania, with the aim of strengthening the support to mining, construction and industrial customers in the Lake Victoria region.

Acknowledgement This article was prepared for the Atlas Copco press lunch in London, December 2005. ■ Drilling in open pit mining

77

navachab, namibia

DTH Choice Cuts Costs at Navachab

The extended main pit at Navachab: Mining is carried out on 5 m-high benches.

Reducing Operational Costs The Navachab gold mine in Namibia has the potential to reduce its operational costs with the introduction of down-the-hole drilling. The mine is aiming for a higher ore-to-waste ratio and substantial savings in loading and haulage.

Substantial Savings

“The full service contract gives us the availability we need to achieve our targets” Angula Kalili, Pit Superintendent.

78

AngloGold Ashanti is proving that substantial savings can be achieved by moving from contractor mining to owner mining.   In 1998–99, AngloGold Ashanti had planned a pit extension programme at its Navachab gold mine that would support production until 2013. At that time, the plant treatment capacity was 170 tonnes per hour, with an ore throughput of 1.4 million tonnes per year, averaging 1.55 grams of gold per tonne.   The low price of gold at that time persuaded the company not to proceed. But after a feasibility study, Navachab approved the Western Pushback, which made up half of the original expansion project. This extension of the main pit from 2000 to 2001 extended the life of the mine (LOM) from 2003 to 2005. In 2002–3, another feasibility project was launched to mine the Eastern Pushback. Through reduced costs and a strong gold price, this project was approved and it increased the LOM to the current 2013.   In 2003, the mine decided not to renew

the mining contractor’s contract and to convert all mining operations to owner mining. This involved the purchase of new mining equipment, including three ROC L8 drill rigs with DTH hammers.   Pit Superintendent Angula Kalili explains: “The aim of selecting DTH drilling was to make the drilling process more accurate, to gain better control of the amount of ore/waste, and to reduce the costs of loading and hauling through better fragmentation.”   Once the Western Pushback (main pit) is complete, it will be 900 m long (extended by 85 m), 375 m wide and 220 m deep (extended by 40 m). Mining of the Eastern Pushback started at the beginning of 2006 and is expected to continue to 2013. All mining blocks (ore and waste) in the main pit are mined out on 5 m high benches. This interval will be the same for ore blocks on the Eastern Pushback but here, waste blocks will be increased to 10 m benches.   The rock is classified as soft, hard and very hard, and each mining block amounts to about 12,000 m3. A dedicated diamond drilling rig works ahead of mining to define the mineralization zones and maximize ore definition. Navachab also operates a comprehensive geotechnical programme including in-pit mapping of structural data to ensure slope stability and provide a safe working environment in terms of geotec wall stability.   Blasting is done with megamite explosives for the pre-split holes and emulsion (High Energy Fuel HEF) for production blast holes, using a powder factor of 0.7 kg/bank m3 in hard rock. Non-electric detonators are used but electronic detonators are being tested for slope stability and vibration control.

Achieving the Objective As a key factor in the switch to DTH drilling, Navachab selected three Atlas Copco ROC L8 drilling rigs equipped with COP 44 hammers for ore drilling and COP 54 hammers for the bigger diameter holes in the waste. These rigs provided exactly the capability Navachab was looking for – high Drilling in Open Pit Mining

DTH choice cuts costs at Navachab

precision drilling, flexibility in feed positioning and a high degree of mobility on the pit’s narrow benches. Kalili explains that the main reason for choosing DTH was to achieve straighter, parallel pre-split holes drilled at the angles required (65–80 degrees) to optimize the slopes. Other factors included good penetration rate and low cost-per-metre.   The rigs have not only achieved those objectives but have also significantly reduced the proportion of blastholes that needed re-drilling prior to blasting, from the 20 per cent previously recorded using top hammer drilling to only five per cent with DTH.   The rigs drill pre-split holes on a 1.2 m spacing, using the COP 44 DTH hammer and 115 mm Secoroc ballistic Speedbits. In waste, the diameter is increased to 140 mm using COP 54 with a 3.5 m x 3.5 m spacing/burden pattern. The benches are drilled with 1 m sub-drill. The daily target drilling rate for all three rigs is set at about 1,000 m corresponding to 20,000–21,000 m/month. Penetration rate has averaged 35 m/hr, mainly with the COP 44 in soft to hard rock. Overall, Navachab has found that the ballistic cone-shaped button bit (Speedbit) performs best in the prevailing conditions. The on-site team regrinds the bits using an Atlas Copco Grind Matic and the bit service life is about 600 m. Atlas Copco supplies the drilling consumables on a contractual basis and is compensated per drill metre in three different rock categories.

Focusing on Full Service The mine emphasizes the importance of full service and easy maintenance. The rigs arrived in April–May 2004 and training was conducted with nine operators. The Atlas Copco service team maintained the rigs for the first year on a full service contract. Mechanics check the oil levels at the start and end of each shift and carry out scheduled workshop services.   “As drilling is crucial for the whole downstream operation, the full service contract gives us the availability we need to achieve our targets,” says Angula Kalili. Experience has shown that it is possible to deliver the mine’s planned production rate using only two of the three units for blasthole drilling, and Kalili would like to see this become routine, freeing the third rig for pre-split drilling and back-up duties. Drilling in Open Pit Mining

Keeping up the good work: During their first year, the ROC L8s were maintained with an Atlas Copco full service contract.

The drilling team: from left, H Nel, Site Foreman, R Rust, Product Support, J Pietersen, Mechanic (all from Atlas Copco), D Stini and M Beukes, Navachab operators and Mathues Pointer, Navachab.

Acknowledgements This article first appeared in Mining & Construction No 2, 2006. ■

DTH drilling under way: The ROC L8s being used for pre-split drilling on a 1.2 m spacing.

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Eisenerz, Austria

Iron Ore From Erzberg Mountain Roman Origins The Erzberg mountain in the Austrian Alps has a history of iron ore mining that dates back to Roman times. The current open pit operation at Eisenerz was started more than a century ago, with 40 benches, each 12 m in height. It survived to become the only iron ore mine still operating in Austria, with probable reserves in excess of 100 million t. Today, the benches are 24 m-high, and the mine consistently produces around 2 million t/year working three, 8 h shifts/day. For production drilling, just a single drillrig is needed. This is a ROC L8 from Atlas Copco.

Improved Capacity

Atlas Copco ROC L8 drilling at Erzberg.

Sampling device fitted to the dust precleaner of the ROC L8.

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The ore at Eisenerz has an iron content of 33.6% and a manganese content of 2%. Recovery rate is 45%, and the beneficiated ore is shipped by rail to the nearby Donawitz and Linz steelworks, where self-fluxing sinter averaging 50% iron and 3% manganese is produced. The operation at the open pit is impressive by any measure, and much of its success can be attributed to clever choice of drilling equipment, perfectly matched to the job. The ROC L8 is used for just one shift/ day, and performs so well that only occasionally, due to quality variations, is there need for an extra shift of drilling. The rig capacity is 40,000 m/year, corresponding to an annual production of 4.4 million t. Prior to investing in the ROC L8, mine owner Voest Alpine Erzberg GmbH used several other rigs. However, the ROC L8 has increased nett drilling capacity at the mine by 100%, up to 50 m/hour. Fuel consumption during operations, including both drilling and tramming up to 2 km/shift, is 40 lit/h. Rig planned maintenance is carried out by mine personnel at the regular service intervals. This is supplemented by an inspection and service by the operator at the start of each shift. This keeps rig availability at 95%. Drilling in Open Pit Mining

Iron Ore From Erzberg Mountain

Erzberg open pit with its 24 m-high benches.

When the ROC L8 was first put to work at the site in 2002, it was equipped with a 6 in DTH hammer, 165 mm bits and 140 mm drill pipes. However, due to the mixed rock conditions, the drillers ran into difficulties, both with flushing of the holes and with the drill string getting stuck. In co-operation with Atlas Copco, the miners switched to a Secoroc COP 54 DTH hammer with 152 mm bit and 127 mm pipes, and the situation improved due to increased air velocity. In addition, Atlas Copco modified the feed of the ROC L8. A more powerful rotation unit, the DHR 48H68, was fitted, giving a maximum torque of 3,600 Nm, together with an upgraded feed motor with a pullout force of up to 5.5 t.

Computerized Planning Every drill hole is planned on computer and the basic drill pattern has a burden and spacing of 6.5 x 6.5 m. Depending on the geology and ground conditions, this is changed from a minimum of 6 m, up to a maximum of 7 m. Hole inclination is 22 degrees off Drilling in Open Pit Mining

vertical and the hole depth, when drilling 24 m-high benches, is 28-29 m. No toe holes are required. The 152 mm bits with ballistic but¬tons are used without regrinding, and have an average life of more than 5,000 m. In homogenous rock, drilling at the rate of 1 m/min is carried out at an air pressure of 25 bar. In mixed ground, the air pressure is reduced to 21 bar to obtain a better balance between penetration rate and flushing capacity. A sampling device fitted to the dust precleaner on the ROC L8 collects powdered iron ore for quality analysis, giving the management an early indication of the expected grade from each hole. The modern miners at Erzberg have since pushed their productivity levels even higher, with Atlas Copco's latest DTH hammer, the COP 54 Gold Express.

Acknowledgements This article first appeared in Mining & Construction, No 3, 2004. ■

81

glentaggart, scotland

More Than a Match for Scotland’s Coal

On site at Scottish Coal’s Glentaggart operation: The versatile ROC L6H.

Exceeding Expectations In the difficult terrain of Scottish Coal’s 150-year-old Glentaggart open cast coal mine, an Atlas Copco ROC L6H is proving more than a match for the larger rotary drill rigs the company operates at its other mines.

Drilling in Sandstone Formerly a room-and-pillar mine, Glentaggart is now recovering remnants of deep mines along its outcrop at a rate of 500,000 tonnes per year. There are some 20 seams here, some of which have been extensively worked, while others are untouched. Proven reserves stand at seven million tonnes. 82

  The drilling is carried out by an Atlas Copco ROC L6H crawler rig with a 25 bar compressor producing 24 m3/m. And this unit, equipped with a COP 54 DTH hammer, a Secoroc 146 mm ballistic bit and using 5mlong drill tubes, produces good results.   The rig is owned by Castlebridge Plant, Scottish Coal’s sister company, which purchases and maintains all of the equipment at the mine and hires it to Scottish Coal.   The rock at Glentaggart consists mostly of sandstone and mudstone. The sandstone is coarse-grained, open-jointed and hard to very hard, making drilling a challenge since fast penetration is accompanied by high abrasion.   But the rig’s large compressed air output, combined with a reduction in tube diameter from 102 mm to 89 mm, has increased tube life and dust collection by slowing the uphole velocity of the drill cuttings caused by high penetration rates in the different rock types.   Depending on whether the rig is drilling in sandstone or mudstone, it achieves a penetration rate of 0.9m/min and 3.5 m/ min. Holes are generally drilled on a 6 m x 6 m pattern.   The relatively small size of the ROC L6H, compared to the rotary rigs at Scottish Coal’s other mines, is appreciated for its vertical, horizontal and angle drilling flexibility.   “It’s a good rig compared to some of the others I have operated,” says its operator, Dean Houston. “It will go places the other rigs simply will not go.”

Good Operational Economy The boom and the feed arrangement can be readily positioned to drill in various directions from vertical to horizontal. The single-section boom design also permits the operator to position the feed from transport mode to drilling in a few minutes without re-pinning.   Toe-holes are simply drilled with the standard boom articulation. Electronic hole inclination and depth control instruments ensure that all blast holes are accurately Drilling in Open Pit Mining

More than a match for Scotland's Coal

aligned and drilled to the predetermined hole depth.   As a result, the operational economy of the ROC L6H at the site has been high. “We get more production out of it,” confirms the mine’s Drilling and Blasting Supervisor, Colin Robb. “That’s the main factor. We can drill more holes in less time.” The mine estimates that the rig averages 40 per cent more production per shift than Scottish Coal’s rotary drill rigs, making it 22 per cent cheaper to run. In addition, fuel consumption is less than 1 litre per metre, making it as fuel efficient as a top hammer rig.   “I know both Scottish Coal and Castlebridge Plant are very happy with this rig,” Mr Robb says. “It has been meeting and exceeding expectations.”   Furthermore, the ROC L6H rig is equipped with a ROPS/FOPS cabin for rollover and falling object protection. This suits the requirements of Scottish Coal which has earned five gold awards in the past six years for health and safety from the UK’s Royal Society for the Prevention of Accidents.   Castlebridge also acquired a second L6H in October for Scottish Coal’s Broken Cross mine on another part of the same coal field.   “We place a lot of importance on safety,” Mr Robb comments. “Besides the cabin, the manoeuvrability of the rig has also made a positive difference especially when working on the slopes. Therefore we can position the rig more safely.

The remote Glentaggart coal field, about 65 kilometres south of Glasgow.

Discussing the day’s performance of the ROC L6H: From left, Dean Houston and Steve Griffiths of Scottish Coal with (right) Atlas Copco’s Mike Wilson.

Acknowledgements This article first appeared in Mining & Construction, No 3, 2004. ■

Drilling in Open Pit Mining

83

Siilinjärvi, finland

Apatite for Extraction Coprod Solution for Siilinjärvi High Productivity The Siilinjärvi open pit mine is the biggest in Finland, extracting almost eleven million tons of apatite a year. Excavation began at the site in 1979 at what is the European Union’s only apatite mine. Today the mine has grown to three kilometres in length, is between 200 and 600 metres wide, and 130 metres deep. According to the owner of the pit, Kemira GrowHow – a leading producer of agricultural fertilizer, there is enough apatite ore at the site to last 40 years.   Siilinjärvi though, has the lowest grade of mineable apatite ore in the world (ten percent apatite in a mineral composition), therefore the need for ultra-efficient extraction is critical to the viability of the operation.

Comparing Drill Rigs

The ROC L740CR drilling 15.5 m deep holes has increased the drilling output by double figures.

Low Grade Apatite Ore When drilling contractor Hartikainen Oy sought a new drill rig fleet for the Siilinjärvi mine, Finland, they had very specific demands. High productivity, reliability, mobility, efficiency and the ability to drill larger, more accurate holes all featured high on the priority list.

84

One of the most important things for the contractor was to find a drill rig that could produce larger diameter holes than most of the other rigs on the market. The need for larger holes is due to the blasting method used at the site: The bench height is typically 14 metres, and the total blast hole depth is 15.5 metres. Waste rock is used to level the uneven surface of the pit so when the drill rig moves to drill the next hole, it first has to drill through 1.5 metres of broken rock. This softer, relatively loose rock demands larger holes in order to remain stable and open for charging.   Minimizing in-hole deviation was another important factor for Hartikainen when se-lecting the drill rigs, for without high drilling and blasting efficiencies, the extraction could become unprofitable. There is a tendancy for in-hole deviation caused by the nature of the rock. The predominant geology of the mine is carbonititic apatite ore and diabase, distributed in veins.   After comparing different manufacturer’s drill rigs and then trying a ROC L740CR onsite for a year, the company knew they had found the ideal rig. Drilling in Open Pit Mining

Apatite for extraction Coprod solution for Siilinjärvi

  The Coprod drilling system used on the ROC L740CR had increased the drilling output by double figures when compared to traditional tophammer and down-the-hole drilling systems. The improvement recorded at the site quickly led to the Siilinjärvi mine becoming first in the world to take delivery of the upgraded Atlas Copco ROC L740CR.   Tuomo Tuohino, Mining Engineer and Project Manager of Kemira GrowHow sums up the performance of the equipment: “The Coprod system, in combination with the overall effectiveness of the drill rig, provides us with exactly what we are looking for.”

Coprod Solution COPROD can make larger holes than traditional tophammer drill rigs, and also produces exceptional hole quality. The upgraded ROC L740CR is equipped with stage3/Tier III engine which meets all the new exhaust emission limits.   The rigs deliver exactly the power needed in each phase of the operation, which considerably reduces fuel consumption. The ROC L740CR also comes with a large fuel tank, enough to allow 12 hours of continuous operation and dependable start-up thanks to the heavy-duty generator and batteries.   The new cabin layout increases cockpit visibility, driver space and comfort, something that has been much appreciated by the crew at Siilinjärvi. Tuomo Tuohino says: “As well as drilling performance, the new ROC L740CR delivers superb operator comfort, a factor that is also plays a part in overall productivity.”   Expanding the mine is much easier now with the diesel driven ROC L740CR, than with the old electric driven non Atlas Copco rigs used previously; the mobility of the new rigs making a significant impact to efficiency of the operation.   The upgraded version of ROC L740CR has compared to its forerunner a bigger engine (328 kW vs 272 kW), more powerful rock drill effect (40 kW vs 30 kW), bigger compressor (254 l/s vs 228 l/s) and can drill larger holes (180 mm vs 165 mm). ROC L740CR. is optimized for difficult rock conditions and therefore ideally suited to the Siilinjärvi mine.   Both mine owner and contractor were very satisfied with the ROC L740CR they Drilling in Open Pit Mining

The Coprod drilling system proved its efficiency when drilling through the 1.5 m deep upper layer of broken rock.

85

Apatite for extraction Coprod solution for Siilinjärvi

From left: Ensio Hartikainen, Arto Hartikainen, Ilkka Eskola, General Manager Oy Atlas Copco Louhintatekniikka AB, and Kari Tiikkaja, Manager of Mining and Construction, Hartikainen.

had rented for a year and therefore have decided to buy two additional units.   Hartikainen place enormous focus on productivity, and the goal for 2007 is to achieve 260,000 drilled meters and 4.3 million cubic meters of extracted material using just three drill rigs. The rigs therefore, have to be very reliable, operating two shifts a day, five days a week.   In order to ensure the proper maintenance of the drill rigs a service and maintenance agreement with Atlas Copco was selected. The agreement, according to Tuomo Tuohino helps to ensure that the demanding pace of production is met: “Our production schedule in drilling and blasting is very demanding, but so far, availability of the drill rigs has been excellent.”

Apatite Apatite is a phosphate mineral and the largest apatite deposits are associated with sedimentary deposits. The mineral is an essential ingredient in phosphate fertilizers, and is also used in the chemical and pharmaceutical industries.

Acknowledgements This article first appeared in Mining & Construction, No 3, 2006. ■

The Siilinjärvi open pit mine is the biggest in Finland.

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Drilling in Open Pit Mining

How to spend less on Secoroc products

The way we figure it is this: If you spend your hard-earned money on drill bits that have to be constantly replaced, then sooner or later you’ll start wondering if you can’t get better value elsewhere. In our case, the answer to this problem was to design a comprehensive range of grinding equipment. It really doesn’t matter what kind of drilling you’re into. We have grinding machines for fixed installations and field operations. We can handle tapered, threaded and DTH button bits as well as integrals with chisel inserts. We also have an ace up our sleeve – a patented diamond grinding wheel. It’s the only one that can give your worn spherical and ballistic buttons a new perfect finish. To start saving money, call your local Atlas Copco representatives today. They may advise you to invest a little first – but hey, we’ve got to make a living too. Atlas Copco Secoroc AB Box 521, SE-737 25 Fagersta, Sweden Phone: +46 223 461 00 E-mail: [email protected] www.atlascopco.com

DRILLING METHOD GUIDE

Drilling method guide Different applications need different kind of drilling equipment and performance. The choice of drilling method is normally already made since long. A well proven technique is very seldom considered to be replaced with a new method. This diagram and table is an attempt to start a discussion around what method and equipment that might be the ultimate solution for an application. This comparison presents our drilling methods and their advantages.

The tophammer method

The classic tophammer method is renowned for high penetration rates in good drilling conditions. Atlas Copco is developing the method continuously. Exhaustive research into how impact energy can be transmitted into the drill bit in the most efficient way, with the least possible stress, has resulted in a new generation of rock drills. Development has been focused on the key component in the rock drill – the piston. The piston length, mass, and geometry have resulted in even faster penetration. The effect is that more rock is crushed with each blow from the piston. Moreover, a double damping system reduces the load on components to give long service life, at the same time as drillsteel wear is reduced. In other words, the positive results of faster drilling are not counteracted by higher drillsteel costs. An extractor unit is available as a useful accessory for poor rock conditions.

Principle: As the name ”tophammer” implies, the rock drill is situated on the rig and works on top of the drillstring. The impact energy of the rockdrill piston is transmitted to the drill bit in the form of shock waves. The method is fast in good rock conditions.

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The down-the-hole method

The down-the-hole method is a reliable way to drill both difficult and easy rock. The rockdrill piston strikes the drill bit directly, while the hammer casing gives straight and stable guidance of the drill bit. This results in minimal deviation and greater holewall stability, even in fissured or otherwise demanding rock. Since the annulus between the drill pipes and the hole wall is comparatively small, a high flushing velocity is maintained, which contributes further to hole quality. Good hole quality enables the burden and spacing to be increased, which saves time and money. Straight holes make charging easier and enable the amount of explosive to be reduced. The reliable DTH method is an easy way to produce deep, straight holes. From an environmental point of view, the noise emissions and vibration from DTH drilling are comparatively low. This is of particular advantage when drilling in densely populated areas.

Principle: The rock drill is situated down the hole in direct contact with the drill bit. This means that power losses are minimal. The hammer’s closeness to the drill bit gives stable guidance and minimal hole deviation.

The COPROD® system

The COPROD system combines the speed of tophammer drilling with the precision and long service life of the down-the-hole method. Inside each rigid, threaded pipe section is an impact rod. It is furnished with stop lugs to hold it in place inside the pipe section. The COPROD sections are joined together via the drill pipes. Since the drill pipes transmit rotation force only, stress to the threads is minimal and their service life very long. All negative effects of the transmission of impact energy through the threads are eliminated entirely. The result is high impact power with minimal wear. Since the outer pipes are smooth and flush along the entire length of the drillstring, it is almost impossible for jamming to occur. Practical experience with COPROD has been exceptionally good. The method gives good overall economy, particularly in large scale production drilling and when drilling in fissured or otherwise demanding rock conditions.

Principle: The rock drill is situated on the feed beam on the rig and impact energy is imparted from above. Threadless impact rods are stacked inside the threaded drill pipes. The impact rods are used solely to transmit impact energy and feed force, while the drill pipes transmit rotation. COPROD combines the speed of tophammer drilling with the hole straightness of the down-the-hole method.

Drilling in open pit mining

DRILLING METHOD GUIDE

Rotary drilling methods

The prime difference from other drilling methods is the absence of percussion. Rotary cutting, using fixed type claw or drag bits, is mainly used for soft rock which is cut by shearing. Rotary crushing uses tricone bits relying on crushing and spalling the rock. This is accomplished by transferring downforce, known as pulldown, to the bit while rotating in order to drive the teeth (commonly tungsten carbide type) into the hole bottom as the three cones rotate around their respective axis. The softer the rock the higher the rotation speed. The drill rigs need to be heavy to avoid lifting off the jacks, which means that they are less flexible and not suited for drilling at different angles. Generally, drilling below 152 mm (6 inches) is best accomplished by percussive drilling unless prevailing rock conditions are suited for rotary cutting. Rotary crushing is the prime choice for large diameter holes, above 254 mm (10 inches) in open pit mining, overburden stripping at coal mines, and deep well drilling.

Drilling Method

Tophammer

DTH

COPROD

Penetration rate Straight holes Hole depth Production capacity (tonnes/shift) Low fuel consumption (lit/drillm.) Economic drill string life Low investment for drill string

TONS

Suitability, difficult drilling conditions

Principle: Rotation is provided by a hydraulic or electric motor driven gearbox, called a rotary head that moves up and down the tower via a feed system, generating the pulldown required to give sufficient weight on the bit. Flushing of drill cuttings between the wall of the hole and the drill rods is normally made with compressed air.

Drilling in open pit mining

Suitability, good drilling conditions Operator friendly Flushing flexibility Fair

Unbeatable in good drilling conditions Low fuel consumption Low investment in drillstring

Good

Straight holes Deep holes Simplicity for the operator

Very good

Unbeatable in difficult drilling conditions High productivity Good penetration rate Visit www.surfacedrilling.com for more information

89

TOPHAMMER DRILL RIG SPECIFICATION

SmartRig™ ROC D7C/D9C Main specifications Recommended hole range D7C T38, T45, T51 Max hole depth, approx Recommended hole range D9C T45, T51 Hole depth Hydraulic rock drill COP 1840-series (ROC D7C) Impact power

The new ROC D7C/D9C crawler drill combines the power and flexibility of the popular ROC D7 with the intelligence of RCS – computerized Rig Control System. RCS adjusts impact and feed to the rock conditions so as to achieve smoother drilling and less wear in the drill steel. Designed both for construction and quarrying work, the ROC D7C/ D9C has a true 102 mm tophammer capability. For bench heights up to 28 m. Fuel efficient diesel engine delivers the power needed for quick penetration and efficient flushing.

Standard equipment

Rig Control System RCS, Operator’s cabin (ROPS and FOPS approved), RHS mechanized rod handlling, Aluminium feed, Double drill-steel support, Angle and hole depth instrument, Fuel saving device, Two-speed traction motors, Dust collector and pre-separator, Feed extension, Air flow control switch, Anti-jamming system, Valves for reduced percussion and air pressures for collaring, Retractable dust hood, Heavy duty tracks, Work lights, Electric refuelling pump

64-115 mm 28 m

2½"-4½" 92'

76-115 mm 28 m

3" - 4½" approx. 92'

18 kW

24.5 HP

COP 2160 (ROC D9C) Impact power, max. 21 kW 28 HP Atlas Copco C 106 screw type compressor ROC D7C Working pressure, max 10.5 bar 152 psi FAD 127 l/s 270 cfm ROC D9C 152 psi Working pressure, max 10.5 bar FAD 136 l/s 288 cfm Engine ROC D7C/D9C Caterpillar water-cooled diesel engine Stage 3/Tier III CAT C7 Rating at 2200 rpm 168 kW 225 HP Boom variants -11, folding boom Fuel tank Capacity 370 l 98 US gal. Feed 23'5" Feed length, total 7135 mm Travel length 4240 mm 15' Feed extension 1400 mm 4'3" Feed rate max. 0.92 m/s 180 ft/min Feed force, max. 20 kN 4400 lbf Coverage area, approx 12 m² 130 sqft Tramming Tramming speed, max. 3.1 km/h 2.0 mph Traction force 115 kN 25760 lbf Hill climbing ability, 20° (30° with winch) Track oscillation ± 12° Ground clearance 455 mm 17½" Transport dimensions Weight, excl. options -11 Folding boom 13600 kg 30000 lb Width 2370 mm 7'10" Length 11610 mm 38'1" Height 3200 mm 10'2"

Optional equipment

Automatic feed alignment, Laser plane receiver, Automatic rod adding system, Hydraulic winch, ROC Manager – MWD, Measure While Drilling, Toe-hole drilling kit, Hydraulic support leg, Silencing kit, Hole Navigation System

25°

3100

25°

4780

2755 5500

90

Drilling in open pit mining

TOPHAMMER DRILL RIG SPECIFICATION

ECM 660 Main specifications

This high performing crawler drill is equipped with a 21 kW reverse percussion hydraulic drifter (HC158) and auto drilling system that offers the combination of high penetration rate, straight holes and long life for consumables. The extendable boom provides for easy and precise hole positioning, and the air conditioned cab for operator’s comfort. The ECM can be used for the hole range 76  -115 mm with T45 or T51 rod in both quarry and construction applications.

Recommended hole range T45, T51 Hole depth, Hydraulic rock drills Montabert/HC158 Impact power, max. Compressor Working pressure, max. FAD Engine Cummins/QSC 8.3 Rating at 2200 rpm Boom variant Type Fuel tank Capacity Feed Feed length, total Travel length Feed extension Feed rate max. Feed force, max. Pull force max. Tramming Tramming speed, max. Traction force, max Hill climbing ability Track oscillation Ground clearance Transport dimensions Weight, excl. o.e Width Length Height

76 -115 mm 25 m

3"- 4½" approx, 82'

21 kW

28 HP

10 bar 167 l/s

140 psi 350 cfm

194 kW

260 HP

Extendable 400 l

106 US gal.

7660 mm 4250 mm 1500 mm 0.7 m/s 19.6 kN 19.6 kN

25' 14' 4'11" 132 ft/min 4400 lbf 4400 lbf

3.4 km/h 89.6 kN 30º ± 9º 420 mm

2.1 mph 20000 lbf

13 tonnes 2.47 m 9.98 m 2.87 m

28660 lb 8'2" 32'9" 9'5"

16'5"

Standard equipment

50 hour element kit, 90 deg. Indexed drill guide, ARC T51 X 12’ X 6 for 72 mm coupling, Auto drilling system (montabert), Auto rod thread greaser, Back mirror, Back up alarm, Drifter hour meter, Dust collector with vertical sliding hood, Engine auto throttle, Full length track guard, HC158 reverse percussion hydraulic drifter, JIC hose fittings, Low level indicator for fuel & hyd. oil, One lever ARC control, Safety shutdown device on drill guide, Standard tool set, Three sets manuals and parts books, Triple grouser shoe pads, Two lever drilling controls, Two speed traction motor, Warning horn, Working lights (F:3/R:1), Limited ambient temperature: 52 deg. C.

Selection of Optional equipment

Accumulator charge kit, Angle indicator 2-d Lim, Angle indicator 3-d lim, Anti freezing system, Arc lockout system, Arc T45 X 12’ X 6 for 63 mm coupling, Arc T45 X 12’ X 6 For 66 mm coupling, Cold wether kit, Extra parts book, Hyd. pressure test kit, Pre skimmer, Single grouser shoe pads, T51 / 77 mm centralizer, Vaposol (less tank), Vaposol tank (asme)

Visit www.surfacedrilling.com for more information

Drilling in open pit mining

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TOPHAMMER DRILL RIG SPECIFICATION

ROC F7 Main specifications

The ROC F7 is available in two versions: a single boom version ideal for quarries; and a folding boom model versatile enough for all manner of construction sites. The ROC F7 is equipped with a double drill steel support and an ergonomically designed cabin.

Standard equipment

Reduced impact pressure mechanism, Anti-jamming system, Automatic feed-force control (RPC), Fuel saving device, Two-speed traction, Dust collector and pre-separator, Double hydraulic drill steel support, Rod handling system (7+1 rods), Feed extension, Heavy duty tracks, Operator’s cabin, ROPS and FOPS approved, Air flow control switch

Recommended hole range T45, T51 76-115 mm Hole depth 28 m Hydraulic rock drill COP 2160 Impact power 21 kW Atlas Copco XAH2 screw compressor Working pressure 10.5 bar 148 l/s FAD Engine Caterpillar Diesel CAT 3126B Rating at 2000 rpm 186 kW Boom variants -10, single boom -11, folding boom Fuel tank Capacity 400 l Feed Feed length, total 8100 mm Travel length 4770 mm Feed rate max. 0.92 m/s Feed force, max. 20 kN Tramming Travel speed, max. 3.6 km/h Traction force 112 kN Hill climbing ability, without winch 20° Hill climbing ability, with winch 35º Track oscillation ± 10º Ground clearance 405 mm Transport dimensions Length folding boom version 13000 mm Length single boom version 12300 mm Width 2490 mm 3200 mm Height folding boom version Height single boom version 3200 mm Weight, optional equipment excluded folding boom version 15700 kg single boom version 15100 kg

3" - 4½" approx. 92'

28.1 HP 152 psi 308 cfm

253 HP

100 US gal. 26'7" 15'8" 180 ft/min 4500 lbf 2.2 mph 25200 lbf 20º 35º ± 10º 16" 42'8" 40'4" 8'2" 10'6" 10'6" 34600 lb 33300 lb

Optional equipment

Hydraulic winch, Hydraulic support leg, Electric refuelling pump, Anti-freeze equipment for compressed air, Air conditioner, heater, Electronic hole depth and inclination instrument, Central lubrication system, Water mist system, TAC tube guides for precision drilling, Thread greasing device

25°

2610

25° 3490

2440 4815

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Drilling in open pit mining

TOPHAMMER DRILL RIG SPECIFICATION

ROC F9/F9LF Main specifications

The ROC F9 crawler drill rig is very powerful in its class, with true 127 mm tophammer capability, and is available with single or folding boom for quarrying and construction. Features the 25 kW COP 2560 rock drill with T51 drill steel for fast penetration and perfect flushing, powered by a fuel-efficient diesel engine.

Standard equipment

Air conditioner, Reduced impact pressure mechanism, Anti-jamming system, Automatic feed-force control, Fuel saving device, Two-speed traction motors, Dust collector and pre-separator, Double hydraulic drillsteel support, Rod-handling system, Feed extension, Heavy-duty tracks, Operator’s cabin, ECM, ROPS and FOPS approved, Air-flow control switch, Water mist system excl. tank, Toe-hole drilling kit, Inclination/depth instrument

Optional equipment

Hydraulic winch, Hydraulic support leg, Electric refuelling pump, Central lubrication system, TAC tube guides for precision drilling, Thread-greasing device, Rock drill extractor, Heater for cabin

Recommended hole range T51 Hole depth Hydraulic rock drill COP 2560 Impact power, max. Atlas Copco screw compressor Working pressure FAD Engine Caterpillar Diesel Stage 3/Tier III Rating at 2000 rpm Boom variants -10, single boom -11, folding boom Fuel tank Capacity Feed Feed length, total -10 and -11 -LF Travel length -10 and -11 -LF Feed extension Feed rate max. Feed force, max. Tramming Tramming speed, max. Traction force Hill climbing ability, Track oscillation Ground clearance Transport dimensions Weight, excl. options ROC F9-10 approx. ROC F9-11 approx. ROC F9LF Width Length -10 and -11 -LF Height

89-127 mm 30 m

3½"-5" 98'

25 kW

33.5 HP

12 bar 213 l/s

175 psi 450 cfm

CAT C9 224 kW

304 HP

400 l

106 US gal.

8100 mm 11230 mm

26'7" 36'10"

4770 mm 7830 mm 1300 mm 0.92 m/s 20 kN

15'8" 25'8" 4'3" 180 ft/min 4500 lbf

3.6 km/h 2.2 mph 112 kN 25200 lbf 20° without winch ± 10º 405 mm 16"

15600 kg 16200 kg 16600 kg 2490 mm

34000 lb 37500 lb 36600 lb 8'2"

12300 mm 11300 mm 3200 mm

40'4" 37' 10'6"

ROC F9LF – For selective mining and single pass drilling Maximize drill time. Minimize inproductive rod changing time. The ROC F9 features a drill feed system for 6.1 m (20 foot) drill rods, with a maximum hole depth of 36 m (118 feet).

25°

2610

25° 3490

2440 4815

Drilling in open pit mining

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TOPHAMMER DRILL RIG SPECIFICATION

SmartRig™ ROC F9C Main specifications

The new ROC F9C crawler drill combines the power and flexibility of the popular ROC F9 with the intelligence of RCS – the computerized Rig Control System. RCS adjusts impact and feed to the rock conditions so as to achieve smoother drilling and less wear in the drill steel. Designed both for construction and quarrying work. Features the 25 kW COP 2560 rock drill with T51 drill steel for fast penetration and perfect flushing, powered by a fuelefficient diesel engine.

Standard equipment

Air conditioner, Reduced impact pressure mechanism, Anti-jamming system, Automatic feed-force control, Fuel saving device, Two-speed traction motors, Dust collector and pre-separator, Double hydraulic drill-steel support, Rod-handling system, Feed extension, Heavy-duty tracks, Operator’s cabin, ECM, ROPS and FOPS approved, Airflow control switch, Water mist system excl. tank, Toehole drilling kit, Inclination/depth instrument

Recommended hole range T51 Hole depth Hydraulic rock drill COP 2560 Impact power, max. Atlas Copco screw compressor Working pressure FAD Engine Caterpillar Diesel Stage 3/Tier III Rating at 2000 rpm Boom variants -10, single boom -11, folding boom Fuel tank Capacity Feed Feed length, total Travel length Feed extension Feed rate max. Feed force, max. Tramming Tramming speed, max. Traction force Hill climbing ability, Track oscillation Ground clearance Transport dimensions Weight, excl. options ROC F9C-10 approx. ROC F9C-11 approx. Width Length Height

89-127 mm 28 m

3½"-5" 92'

25 kW

33.5 HP

12 bar 213 l/s

175 psi 450 cfm

CAT C9 224 kW

304 HP

400 l

106 US gal.

8100 mm 4770 mm 1300 mm 0.92 m/s 20 kN

26'7" 15'8" 4'3" 180 ft/min 4500 lbf

3.6 km/h 2.2 mph 112 kN 25200 lbf 20° without winch ± 10º 405 mm 16"

15600 kg 16200 kg 2490 mm 12300 mm 3200 mm

34000 lb 37500 lb 8'2" 40'4" 10'6"

Selection of optional equipment

Automatic feed alignment, Automatic rod adding system, Hydraulic winch, Hydraulic support leg, Thread greasing device, Heater for cabin, Hole Navigation System

Visit www.surfacedrilling.com for more information

25°

2610

25° 3490

2440 4815

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Drilling in open pit mining

TOPHAMMER DRILL RIG SPECIFICATION

ECM 720 Main specifications

ECM 720 provides a perfect balance of high productivity and cost efficiency. The combination of powerful HC 200A rock drill and the Strata Sense drilling control system allows you to drill through various rock conditions with high penetration rate and yet drilling straight holes. The extension boom helps quick and accurate collaring. Like the rest of the 700 series, simplicity of the 720 makes it easy to operate and easy to maintain.

Standard equipment

115 - 140 mm 29.5 m

4½"- 5½" 97'

26 kW

35 HP

10.3 bar 226 l/s

150 psi 480 cfm

287 kW

385 HP

Telescopic 587 l

~155 US gal.

8788 mm 5182 mm 1524 mm 0.96 m/s 33.8 kN 33.8 kN

28'10" 17' 5' 190 ft/min 7600 lbf 7600 lbf

3.2 km/h 125.4 kN 30° ± 10° 432 mm

2.0 mph 28192 lbf

20.5 tonnes 2.57 m

45300 lb 8'5"

10.72 m 3.94 m

35'2" 12.11"

12.17m 3.33 m

39'11" 10'11"

17"

-6°

22°

94°

Mechanized rod handling, Automatic throttle, AntiJamming, Load sense progressive anti jamming system (Strata Sense), Central hydraulic system test port, Variable speed cooling fan control, Tier III emission compliance, 2D electronic angle indicator, Boom extension, Feed extension, Dual pinning for L/R horizontal drilling, Water mist system preplumbed for tank, Preseparator, Dust collector, Retractable dust hood, Hydraulic centralizer, Thread greasing device, FOPS and ROPS operator safety cab, Cab air-conditioning, Working lights, Back up alarm, Heavy duty tracks with full length rock guards, Track oscillation

Recommended hole range Hole range Hole depth Hydraulic rock drill HC200A Impact power, max. Compressor Working pressure, max FAD Engine CAT C11 Rating at 1800 rpm Boom variants Type Fuel tank Capacity Feed Feed length, total Travel length Feed extension Feed rate max. Feed force, max. Pull force, max. Tramming Tramming speed, max. Traction force Hill climbing ability, Track oscillation Ground clearance Transport dimensions Weight, excl. o.e Width Reaching shortest length Length Height Reaching lowest height Height Height lowest

Selection of optional equipment

Visit www.surfacedrilling.com for more information -6°

3D angle indicator, 3D angle indicator with speed and depth, Central lubrication system, 14’ rod changer group, High capacity dust collector, Hydraulic system test kit, Conversion kit T51/T60, Pressurized water mist tank 80 gal, Pressurized water mist tank 120 gal instead of DCT, Cold ambient kits 90°

22°

94°

30°

14°

90°

30°

Drilling in open pit mining

14°

95

TOPHAMMER DRILL RIG SPECIFICATION

ROC L7 Main specifications

The new ROC L7 drill rig offers an economic alternative with an extraordinary performance in its hole range. Large scale work sites, and quarries with high demand on productivity, are in focus. The standard drill rig is designed to operate within the most demanding production environment. We also provide the short feed version for the contract drilling and more difficult operating environments.

Standard equipment

Recommended hole range T51 Hole depth Hydraulic rock drill COP 4050 Impact power, max. Atlas Copco screw compressor Working pressure FAD Engine Caterpillar Diesel Stage 3/Tier III Rating at 2000 rpm Boom variants Single boom Fuel tank Capacity Feed Feed length, total Travel length Feed extension Feed rate max. Feed force, max. Tramming Tramming speed, max. Traction force Hill climbing ability, Track oscillation Ground clearance Transport dimensions Weight, excl. options Width Length Height

89-127 mm 36 m

4"- 5" 120'

40 kW

54 HP

12 bar 254 l/s

171 psi 540 cfm

CAT C13 328 kW

417 HP

760 l

201 US gal.

11400 mm 7500 mm 1150 mm 0.9 m/s 40 kN

37' 25' 59" 177 ft/min 8992 lbf

1.7/3.5 km/h 124/49 kN

1.2/2.2 mph 27876/ 11016 lbf

20° + 10º/-8 405 mm

16"

23700 kg 2500 mm 11500 mm 3500 mm

52250 lb 8'2" 39'4" 11'6"

RHS 102 Rod magazine, Stroke length selection in cabin, Engine monitoring, hole inclination and drill depth instrument, Dust collector and pre-separator , Automatic cleaning system, 12 hours fuel capacity, Fuel tank in steel, Hydraulic oil - Mineral, Manual Hydraulic oil filling system, Stepless flushing regulation in cabin, Triple track chain grouser pads, Electrical outlet 12VDC, Feed lightening

Optional equipment

Visit www.surfacedrilling.com for more information

Short feed

A

B

96

2440 2140

2140

2440

25º

13º

21º

Long feed

25º

Service winch on feed, Thread greasing device , Diesel driven cabin heater, Sun shade kit for cab, Reversing camera, Compressor regulation heating kit, Fire suppression system Manual / Automatic, Central lubrication system

A Long feed 582 Short feed 1040 B Long feed 2277 Short feed 2659

Drilling in open pit mining

TOPHAMMER ROCK DRILL SPECIFICATIONS

Hydraulic rock drills

COP 2160/2560

Top hammer rock drills for hole diameter range 89-127 mm Updated hydraulic rockdrills COP 2160 and COP 2560 are among the most powerful rock drills on the market. The main differences from the earlier COP 2150/2550 series are a 10 mm bigger adapter, increased bearing surface, larger driver and an impact piston with a greater diameter at the striking end. The reason for the changes is to give even better impact tolerance for really heavy production work. But there’s another important point: COP 2560 can be used not only with the T51 drill steel but also with the ThunderRod T60 for hole diameters of 102 mm and above. This drill steel has a 40 percent larger cross sectional area than the T51 and is therefore considerably more rigid. The resulting reduced hole deviation allows less dense hole planning and gives rise to significant savings in drilling time. Both models can be delivered with inbuilt extractors, identified by the suffix EX.

COP 2560

COP 2160EX

COP 2560

Technical data

Weight Length Impact power, max Impact rate Hydraulic pressure, max Rotation speed range, max Rotation pressure, max Rotation motor size (OMS 315) Drill steel torque, max Flushing air pressure Lubricating air consump. at 2 bar Shank adapter

Drilling in open pit mining

COP 2160

187 kg 1138 mm 21 kW 36 Hz 210 bar 0-110 rpm 200 bar -10 1810 Nm 12 bar 5 l/s T45,T51

COP 2160EX

249 kg 1336 mm 21 kW 36 Hz 210 bar 0-110 rpm 200 bar -10 1810 Nm 12 bar 5 l/s T45,T51

COP 2560

187 kg 1138 mm 25 kW 44 Hz 230 bar 0-110 rpm 200 bar -10 1810 Nm 12 bar 5 l/s T51,T60

COP 2560EX

249 kg 1336 mm 25 kW 44 Hz 230 bar 0-110 rpm 200 bar -10 1810 Nm 12 bar 5 l/s T51,T60

97

TOPHAMMER ROCK DRILL SPECIFICATIONS

COP 1838HE

Top hammer rock drill for hole diameter range 76 – 115 mm

COP 1838HE is specially suitable for medium to large hole sizes. Adjustable stroke length makes it possible to adjust impact rate and energy to actual rock conditions and hole size. Powerful, stepless variable and reversible rotation motor gives high torque and excellent speed control. The efficient reflex damping system of the COP 1800 series is called “dual damping” due to its high

efficiency and double acting function. As the feed and the boom are not subjected to unnecessary strain, the entire drill string will give you longer service life. The automatic tightening system of the drill string results in straighter holes and optimum penetration. COP 1838HE can also be supplied with built-in hydraulic extractor. Technical data COP 1838HE COP 1838HEX Weight 174 kg 226 kg Length 1098 mm 1296 mm Impact power, max 19 kW 19 kW Impact rate 42-50 Hz 42-50 Hz Hydraulic pressure, max 230 bar 230 bar 0-130 rpm 0-130 rpm Rotation speed range, max Rotation pressure, max 200 bar 200 bar Rotation motor size (OMS 250) -09 -09 Drill steel torque, max 1500 Nm 1500 Nm Flushing air pressure 10 bar 10 bar Lubricating air consump. at 2 bar 6 l/s 6 l/s Shank adapter        T45, T51

COP 1840HE Top hammer rock drill for hole diameter range 76 – 115 mm COP 1840HE is specially suitable for heavy duty drilling, e.g. when using TDS-type guide tubes to obtain straighter holes. Adjustable stroke length makes it possible to adjust impact rate and energy to actual rock conditions and hole size. Powerful, stepless variable and reversible rotation motor gives high torque and excellent speed control. The efficient reflex damping system of the COP

1800 series is called “dual damping” due to its high efficiency and double acting function. As the feed and the boom are not subjected to unnecessary strain, the entire drill string will give you longer service life. The automatic tightening system of the drill string results in straighter holes and optimum penetration. COP 1840HE can also be supplied with built-in hydraulic extractor. Technical data COP 1840HE COP 1840HEX Weight 184 kg 244 kg Length 1138 mm 1336 mm Impact power, max 19 kW 19 kW Impact rate 42-50 Hz 42-50 Hz Hydraulic pressure, max 230 bar 230 bar 0-130 rpm 0-130 rpm Rotation speed range, max Rotation pressure, max 200 bar 200 bar -09 -09 Rotation motor size (OMS 250) Drill steel torque, max 1500 Nm 1500 Nm Flushing air pressure 10 bar 10 bar Lubricating air consump. at 2 bar 6 l/s 6 l/s Shank adapter        T45, T51

COP 4050ME

Top hammer rock drill for hole diameter range 89 – 127 mm

A heavy-sized hydraulic top hammer with an impact output of up to 40 kW. It is specially designed for continuous, heavy duty bench drilling. It is equipped with two powerful hydraulic rotation motors which minimizes the risk of jamming. Impact and power levels are easily adjustable to prevailing rock conditions for achieving good hole quality, long drill steel life and an overall high productivity.

COP 4050ME can also be supplied with a built in extractor device (COP 4050MEX), which further improves drilling capacity and economy by practically eliminating the risk of losing the drill string if it gets stuck. It is obvious that the extractor is an investment which soon pays for itself in difficult ground conditions through fewer disruptions, better hole quality and increased steel life. Technical data COP 4050ME Weight, (incl.adapter) 390 kg Length, (without adapter) 1293 mm Impact power, max 40 kW Impact rate 40-60 Hz Hydraulic pressure, max 230 bar 0-110 rpm Rotation speed range, max Rotation pressure, max 200 bar Rotation motor size (OMS 250) 2× -09 Rotation torque, max 3500 Nm Flushing air pressure 8 bar Lubricating air 4 bar Shank adapter, male           T51

98

COP 4050MEX

420 kg 1546 mm 40 kW 40-60 Hz 230 bar 0-110 rpm 200 bar 2× -09 3500 Nm 8 bar 4 bar

Drilling in open pit mining

TOPHAMMER DRILLING TOOLS

Bench and production drilling

Drilling in open pit mining

99

TOPHAMMER DRILLING TOOLS

Bench and production drilling

100

R/  T38 (1 1⁄2")

Drilling in open pit mining

TOPHAMMER DRILLING TOOLS

Bench and production drilling

Drilling in open pit mining

R/  T38 (1 1⁄2")

101

TOPHAMMER DRILLING TOOLS

Bench and production drilling

102

R/  T38 (1 1⁄2")

Drilling in open pit mining

TOPHAMMER DRILLING TOOLS

Bench and production drilling

Drilling in open pit mining

T45 (1 3⁄4")

103

TOPHAMMER DRILLING TOOLS

Bench and production drilling

104

T45 (1 3⁄4")

Drilling in open pit mining

TOPHAMMER DRILLING TOOLS

Bench and production drilling

Drilling in open pit mining

T45 (1 3⁄4")

105

TOPHAMMER DRILLING TOOLS

Bench and production drilling

106

T51 (2")

Drilling in open pit mining

TOPHAMMER DRILLING TOOLS

Bench and production drilling

Drilling in open pit mining

T51 (2 ")

107

TOPHAMMER DRILLING TOOLS

Bench and production drilling

T51 (2")

A bit of evolution

108

Drilling in open pit mining

TOPHAMMER DRILLING TOOLS

Bench and production drilling

Drilling in open pit mining

T60 (2 3⁄8")

109

COPROD DRILL RIG SPECIFICATION

COPROD ® System Straight and fast drilling in demanding rock used to be a ­ production planner’s dream. However, with the advent of COPROD, the patented tophammer drilling system developed by Atlas Copco, the dream has been translated into reality. COPROD provides a drill string that combines the hole straight­ness of downthe-hole drilling with the speed of the tophammer system. The COPROD drill string is a combination of impact rods and drill pipes: the impact rods transmit impact energy and feed force only, while the drill pipes transmit ­ rotational torque and flushing.

COP 2000CR series rock drills are designed for the 90 -127 mm hole range.

through the threads are eliminated, resulting in high impact power with minimal wear. Since the outer pipes are smooth and flush along the entire length of the drillstring, it is almost impossible for jamming to occur.

Impact Rods Inside each COPROD section is a floating impact rod. These have no threads, which means that the impact shock waves from the rock drill are transmitted directly down to the drill bit, with no energy losses. Each impact rod is fur­nished with stop Iugs to hold it in place inside the pipe section. The rock drill is mounted on the feed beam of the rig, and impact energy is imparted from above.

Straight Holes

Atlas Copco ROC F9CR production drill rig is fitted with the COPROD system.

Drill Pipes The COPROD sections are joined to­gether via the drill pipes. Since the drill pipes transmit rotation force only, stress to the threads is mini­mal, and their service life is very long. The normal effects of the transmis­sion of impact energy

The benefits of straight holes include: a more widely spaced drilling pattern with fewer holes, saving time and money; trouble-free charging with ­dramatically reduced explosives consumption; more evenly distributed charges, reducing ground vibration, blasting noise, and risk of flyrock; more regular fragmentation, avoiding the costly ­ secondary blasting needed to pop oversize boulders; smoother bench floors, requiring less extra work; and fewer stuck drill rods, decreasing the time required to remove rods from the hole.

Business end of the ROC F7CR, an engineering masterpiece.

Production Economy For total production economy, the speed and precision of drilling, combined with the long service life of its components, makes the COPROD system an unbeatable combination. Practical experience with COPROD drilling has confirmed the theoretical benefits. The method gives good overall economy, particularly in large-scale production drilling, and when drill­ing in fissured or otherwise demanding rock conditions.

Section of COPROD drill string shows the floating impact rod within the drill pipe.

110

Drilling in open pit mining

COPROD DRILL RIG SPECIFICATION

ROC F7CR Main specifications

The ROC F7CR is available with a single boom ideal for quarrie. The ROC F7CR is equipped with a double drill pipe support and an ergonomically designed cabin.

Standard equipment

Reduced impact pressure mechanism, Antijamming system, Automatic feed-force control (RPC-F), Fuel saving device, Two-speed traction, Dust collector and pre-separator, Double hydraulic drill pipe support, with break-out table, Rod handling system (7+1 sections), Feed extension, Heavy duty tracks, Operator’s cabin, ROPS and FOPS approved, Air flow control switch, Air conditioner

Recommended hole range CR76, CR89 90-127 mm Hole depth 28 m Hydraulic rock drill COP 2150CR Impact power 21 kW Atlas Copco XAH2 screw compressor Working pressure 10.5 bar FAD 148 l/s Engine Caterpillar Diesel CAT 3126B Rating at 2000 rpm 186 kW Boom variants single boom Fuel tank Capacity 400 l Feed Feed length, total 8100 mm Travel length 4770 mm Feed rate max. 0.92 m/s Feed force, max. 20 kN Tramming Travel speed, max. 3.6 km/h Traction force 112 kN Hill climbing ability, without winch 20° Hill climbing ability, with winch 35º Track oscillation ± 10º Ground clearance 405 mm Transport dimensions Length 12300 mm Width 2490 mm Height 3200 mm Weight, optional equipment excl. 15800 kg

3½" - 5" approx. 92'

28.1 HP 152 psi 314 cfm

253 HP

100 US gal. 26'7" 15'8" 180 ft/min 4500 lbf 2.2 mph 25200 lbf 20º 35º ± 10º 16" 40'4" 8'2" 10'6" 34800 lb

Optional Equipment

Hydraulic winch, Hydraulic support leg, Electric refuelling pump, Anti-freeze equipment for compressed air, heater, Electronic hole depth and inclination in-strument, Central lubrication system, Water mist system

Visit www.surfacedrilling.com for more information

25°

1 090 mm

25° 2 560 mm

A B

Drilling in open pit mining

111

COPROD DRILL RIG SPECIFICATION

ROC F9CR Main specifications

The ROC F9CR crawler drill rig is very powerful in its class, with true 127 mm tophammer capability, and is available with single boom for quarrying. Features the 25 kW COP 2550 rock drill with COPROD drill steel for fast penetration and perfect flushing, powered by a fuelefficient diesel engine.

Standard equipment

Air conditioner, Reduced impact pressure mechanism, Anti-jamming system, Automatic feed-force control, Fuel saving device, Two-speed traction motors, Dust collector and pre-separator, Double hydraulic drillpipe support, Rod-handling system, Feed extension, Heavy-duty tracks, Operator’s cabin, ECM, ROPS and FOPS approved, Airflow control switch, Water mist system excl. tank, Toehole drilling kit, Inclination/depth instrument

Recommended hole range CR76, CR89 Hole depth Hydraulic rock drill COP 2550CR Impact power, max. Atlas Copco screw compressor Working pressure FAD Engine Caterpillar Diesel Stage 3/Tier III Rating at 2000 rpm Boom variants Single boom Fuel tank Capacity Feed Feed length, total Travel length Feed extension Feed rate max. Feed force, max. Tramming Tramming speed, max. Traction force Hill climbing ability, Track oscillation Ground clearance Transport dimensions Weight, excl. options Width Length Height

90-127 mm 28 m

3½"-5" 92'

25 kW

33.5 HP

12 bar 210 l/s

175 psi 450 cfm

CAT C9 224 kW

304 HP

400 l

106 US gal.

8100 mm 4770 mm 1300 mm 0.92 m/s 20 kN

26'7" 15'8" 4'3" 180 ft/min 4500 lbf

3.6 km/h 2.2 mph 112 kN 25200 lbf 20° without winch ± 10º 405 mm 16" 17300 kg 2490 mm 12300 mm 3200 mm

38100 lb 8'2" 40'4" 10'6"

Optional equipment

Hydraulic winch, Hydraulic support leg, Electric refuelling pump, Central lubrication system Visit www.surfacedrilling.com for more information

25°

1 090 mm

25° 2 560 mm

A B

112

Drilling in open pit mining

COPROD DRILL RIG SPECIFICATION

ROC L7CR Main specifications Recommended hole range CR89, CR102, CR127, CR140 Hole depth, max. Hydraulic rock drill COP 4050CR Impact power, max. Atlas Copco screw compressor Working pressure FAD Engine Caterpillar Diesel stage 3/Tier III Rating at 2000 rpm Boom variants single boom Fuel tank Capacity Feed Feed length, total Travel length Feed extension Feed rate max. Feed force, max. Tramming Tramming speed, max. Traction force

The ROC L7CR drill rig offers an economic alternative with an extraordinary performance in its hole range. Large scale work sites, and quarries with high demand on productivity, are in focus. The standard drill rig is designed to operate within the most demanding production environment. We also provide the short feed version for contract drilling.

Hill climbing ability Track oscillation Ground clearance Transport dimensions Weight, excl. options Width Length Height

Standard equipment

RHS 102 Rod magazine, Engine monitoring, Hole inclination and drill depth instrument, Dust collector and pre-separator, Automatic cleaning system, 12 hours fuel capacity, Fuel tank in steel, Hydraulic oil - Mineral, Manual hydraulic oil filling system, Stepless flushing regulation in cabin, Triple track chain grouser pads, Electrical outlet 12VDC, Feed lightening

105 -180 mm 36 m

4"- 7" 120'

40 kW

54 HP

12 bar 254 l/s

171 psi 540 cfm

CAT C13 328 kW

417 HP

760 l

201 US gal.

12200 mm 7500 mm 1150 mm 0.9 m/s 40 kN

40' 25' 59" 177 ft/min 8992 lbf

1.7/3.5 km/h 124/49 kN

1.2/2.2 mph 27876/ 11016 lbf

20° + 10º/-8 405 mm 24600 kg 2500 mm 12200 mm 3500 mm

16" 54230 lb 8'2" 40' 11'6"

Optional equipment

Gas charging equipment, Extractor, Service winch on feed, Rock drill stroke length selection in cabin, Diesel driven cabin heater, Cab windows tinted, Cab windows laminated, Wind shield dryer for right window, Sun shade kit for cab, Electrical heated operators seat, Reversing camera, Radio/ CD, Canopy lighting, Safety rails on canopy, Beacon, ProCOM, Engine monitoring, Hole inclination and drill depth instrument with laser receiver, Compressor regulation heating kit, Hydraulic oil - Tropical/ Artic/Bio oil, Statoil Hydraway, Bio Pa 46, Diesel driven engine pre-heater, Ether start for engine, Fire suppression system Manual/ Automatic, Central lubrication system, Service lamp inside canopy, Water mist - Pre-plumed, Water mist - 225l pressurised tank, Water mist - 400l non pressurised tank

Visit www.surfacedrilling.com for more information

A

B

Drilling in open pit mining

2140

2440

25º 2140

2440

25º

Short feed

13º

21º

Long feed

A Long feed 582 Short feed 1040 B Long feed 2277 Short feed 2659

113

COPROD ROCK DRILL SPECIFICATIONS

Hydraulic rock drills COP 2150CR, COP 2550CR

Top hammer rock drill for hole diameter range 90 – 127 mm The COP 2150CR and COP 2550CR together with their respective COPROD® drillstrings provide a fast and reliable means of working in demanding rock formations. These rock drills are equipped with two hydraulic rotation motors with a torque output well suited to their respective hole diameter ranges. High torque reduces the risk of jamming and gives smooth rotary action that

eases stress to the equipment. Success of the original COPROD system has stimulated the development of rock drills and additional drillstrings. COP 2150CR is used in the hole range 90 -115 mm in combination with the COPROD 76 or 89 drillstrings. In the hole range 90 -127 mm COP 2550CR rock drill with COPROD 89 is recommended. Technical data COP 2150CR COP 2550CR Weight, (incl. adapter) 242 kg 242 kg Length, (with adapter) 1661 mm 1661 mm Impact power, max 21 kW 25 kW Impact rate 36 Hz 44 Hz Hydraulic pressure, max 210 bar 230 bar Rotation speed range, max 0-100 rpm 0-100 rpm Rotation pressure, max 200 bar 200 bar 2• -10 2• -10 Rotation motor size (OMS 315) Drill steel torque, max 4000 Nm 4000 Nm Flushing air pressure 12 bar 12 bar Lubricating air 3 bar 6 bar Shank adapter      CR 76, CR 89

COP 4050CR

Top hammer rock drill for hole diameter range 105 – 180 mm COP 4050ME-CR and COP 4050HE-CR together with their respective COPROD® drillstrings provide a fast and reliable means of working in demanding rock formations. These rock drills are equipped with two hydraulic rotation motors with a torque output well suited to their respective hole diameter ranges. High torque reduces the risk of jamming and gives smooth rotary action that eases stress to the equipment. Success of the original COPROD system has stimulated the development of rock drills and additional drillstrings. COP 4050ME-CR is used in the hole range 105-140 mm in combination with the COPROD 89 and 102 drillstrings. In the hole range 140-180 mm COP 4050HE-CR and 127 and 140 is recommended.

Technical data

COP 4050ME-CR COP 4050HE-CR

Weight, (incl. adapter) 435 kg 435 kg Length, (without adapter) 1780 mm 1780 mm Impact power, max 40 kW 40 kW Impact rate 40-60 Hz 40-60 Hz Hydraulic pressure, max 230 bar 230 bar Rotation speed range 0-95 rpm 0-95 rpm 200 bar Rotation pressure, max 200 bar Rotation motor size (OMS 315) 2• -10 2• -10 Drill steel torque, max 4200 Nm 4200 Nm Flushing air pressure, max 8 bar 8 bar Lubricating air 4 bar 4 bar Tube adapter, male CR 89, CR 102, CR 127, CR140

CIAA AB

114

Drilling in open pit mining

COPROD DRILLING TOOLS

COPROD

Drilling in open pit mining

COPROD 76 and 89 for COP 1838CR, 1850CR, 2150CR, 2550CR

115

COPROD DRILLING TOOLS

COPROD

116

COPROD 89, 102 and 127 for COP 4050CR

Drilling in open pit mining

COPROD DRILLING TOOLS

COPROD

Drilling in open pit mining

Drill bits

117

DTH DRILL RIG SPECIFICATION

CM 760D Technical data

The CM 760D offers excellent performance and low operating costs when drilling with 4” DTH hammers. A single joystick handles the drill tube changer, and another joystick controls tramming. Operators particularey like the excellent visibility during drilling and tramming. Routine service items are located for ground level service

Standard equipment

110 -130 mm 102 -140 mm 102 -127 mm 76/89/102 mm 4 m 30 m

Compressor Type Working pressure FAD

2-stage Rotary Screw 24 bar 350 psi 297 l/s 630 cfm

Engine Caterpillar Diesel Rating at 1800 rpm

CAT C11 Tier III Compliant 287 kW 385 HP

Fuel tank Total capacity

587 l

155 US gal.

Feed Feed length, total Travel length Feed extension Feed rate, max. Feed force, max.

6579 mm 4293 mm 1219 mm 0.76 m/s 43.6 kN

21'7" 14'1" 4' 149 ft/min 9800 lbf

Tramming Tramming speed, max. Traction force Hill climbing ability Track oscillation Ground clearance

3.2 km/h 125.4 kN 30° ± 10º 432 mm

2 mph 28192 lbf

Hydraulic Rotation unit Max speed Torque max, drilling Max torque

0 - 120 rpm 2820 Nm 4067 Nm

2080 ft.lbf 3000 ft.lbf

22200 kg 2570 mm

49000 lbs 8'5"

10680 mm 3300 mm

35'½" 10'8"

10820 mm 3070 mm

35'6" 10'1"

Transport dimensions Weight, excl. options Width Reaching shortest length Length Height Reaching lowest height Length Height

45⁄16" - 51⁄8" 4" - 51⁄2" 4" - 5" 3" - 4" 13', 1½" 98.5 ft

17"

98.25

101.25

22°

90°

Mechanized pipe handling, Automatic throttle, Central hydraulic system test port, Variable speed cooling fan control, Max engine rpm control, Tier III emission compliance, 2D electronic angle indicator, Feed extension, Dual pinning for L/R horizontal drilling, Water mist system preplumbed for tank, Preseparator, Dust collector, Retractable dust hood, Tread greasing device, FOPS and ROPS operator safety cab, Cab air-conditioning, Working lights, Back up alarm, Heavy duty tracks with full length rock guards, Track oscillation, Variable air volume control for collaring , DTH hammer lubricator device (pneumatic)

Recommended hole range Recommended Optional DTH Hammer Drill tube diam. Drill tube length Hole depth, max.

Optional Equipment

3D angle indicator, 3D angle indicator with speed and depth, Central lubrication system, Auxiliary winch for loading pipes, High capacity dust collector, Hydraulic system test kit, Wrenches, Non-pressurized water mist tank 80 gal, Non-pressurized water mist tank 120 gal instead of DCT, Cold ambient kits, DTH hammer lubricator device (electric) 90°

8°

Visit www.surfacedrilling.com for more information 8° 90° 22°

90°

30°

14°



98.25 30°

118

14°

101.25

Drilling in open pit mining

DTH DRILL RIG SPECIFICATION

ROC L6 Technical data

ROC L6 is a high-capacity down-the-hole crawler for quarry drilling in soft, medium and hard rock, with a power unit that delivers compressed air at a full 25 bar. With the powerful CAT C11 diesel engine the ROC L6 not only provides power but economy.

Standard equipment

Air conditioning, Tube handling system (capacity of 8 tubes), Fuel saving device, Two-speed traction motors, Dust collector and pre-separator, Feed extension, Operator’s cabin (ROPS and FOPS approved), Atlas Copco electronic hole depth/inclination instrument, Reduced air pressure for collaring, Break-out table, Retractable suction hood, Track chains with triple grouser pads, Hydraulic support leg, Toe hole drilling kit

Optional equipment

Central lubrication system, Electric refuelling pump, Water mist systems, Track chains with single grouser pads, Hydraulic support leg, Heavy duty air intake filters for engine and compressor, Cold weather kits including engine heater, Heating system for cabin, Cab windows laminated, Cab windows tinted, Radio and CD player, Sun shades for cab windows, Electric heated operator’s seat

Recommended hole range COP 34/34Q COP 44/44Q COP 54 COP 54HD Drill tube diam. Drill tube length Hole depth, max.

90 -105 mm 110 -130 mm 134 -152 mm 140 -152 mm 76/89/102 mm 5 m 45 m

Compressor Atlas Copco Working pressure, max. FAD

XRV 9 screw compressor 25 bar 363 psi 295 l/s 625 cfm

Diesel Engine Caterpillar Rating at 2000 rpm

CAT C11 Tier III Compliant 287 kW 385 HP

Fuel tank Capacity

780 l

206 US gal.

Feed Feed length, total Travel length Feed extension Feed rate, max. Feed force, max. Tractive pull, max.

8760 mm 5420 mm 1300 mm 0.92 m/s 20 kN 30 kN

28'9" 17'9" 4'3" 180 ft/min 4496 lbf 6749 lbf

Tramming Tramming speed, max. Traction force Hill climbing ability Track oscillation Ground clearance

3.4 km/h 120 kN 20° +10º - 8° 405 mm

2.1 mph 26980 lbf 16"

Hydraulic Rotation unit DHR 48H45 Max speed (rpm)1 112 Max torque (Nm)2 1800 Max flow (l/min) 123 1 Not in combination with max torque 2 at max pressure at 125 bar (1812 psi) Transport dimensions Weight approx. excl. options Width Length* Height* Length** Height** *feed in forward position **feed dumped on canopy

39/16" - 41/8" 45/16" - 51/8" 51/4" - 6" 51/2" - 6" 3"/3½"/4" 16'5" 148'

1330 lbf/ft 260 cfm

19000 kg 2500 mm 13600 mm 3110 mm 10650 mm 4075 mm

41900 lb 8'2" 44'7" 10'2" 34'11" 13'37"

Visit www.surfacedrilling.com for more information

35°

14° 36°

25°

25°

95°

2440 2140 8760

3030

ROC L6

2820 3550

1900

5450

Drilling in open pit mining

119

DTH DRILL RIG SPECIFICATION

ROC L6H Technical data

ROC L6H is a high-capacity down-the-hole crawler for quarry drilling in soft, medium and hard rock, with a power unit that delivers compressed air at a full 25 bar. With the powerful CAT C13 diesel engine, the ROC L6H provides sufficient power for the most demanding drilling conditions.

Standard equipment

Air conditioning, Tube handling system (capacity of 8 tubes), Fuel saving device, Two-speed traction motors, Dust collector and pre-separator, Feed extension, Operator’s cabin (ROPS and FOPS approved), Atlas Copco electronic hole depth/inclination instrument, Reduced air pressure for collaring, Break-out table, Retractable suction hood, Track chains with triple grouser pads, Hydraulic support leg, Toe hole drilling kit

Optional equipment

Central lubrication system, Electric refuelling pump, Water mist systems, Track chains with single grouser pads, Heavy duty air intake filters for engine and compressor, Cold weather kits including engine heater, Heating system for cabin, Cab windows laminated, Cab windows tinted, Radio and CD player, Sun shades for cab windows, Electric heated operator’s seat

Recommended hole range COP 44/44Q COP 54 COP 54HD Drill tube diam. Drill tube length Hole depth, max.

110 -130 mm 134 -152 mm 140 -152 mm 76/89/102 mm 5 m 45 m

Compressor Atlas Copco Working pressure, max. FAD

XRV 9 screw compressor 25 bar 363 psi 405 l/s 858 cfm

Diesel Engine Caterpillar Rating at 2000 rpm

CAT C13 Tier III Compliant 328 kW 440 HP

Fuel tank Capacity

780 l

206 US gal.

Feed Feed length, total Travel length Feed extension Feed rate, max. Feed force, max. Tractive pull, max.

8760 mm 5420 mm 1300 mm 0.92 m/s 20 kN 30 kN

28'9" 17'9" 4'3" 180 ft/min 4496 lbf 6749 lbf

Tramming Tramming speed, max. Traction force Hill climbing ability Track oscillation Ground clearance

3.4 km/h 120 kN 20° +10º -8° 405 mm

2.1 mph 26980 lbf 16"

Hydraulic rotation unit DHR 48H45 Max speed (rpm)1 112 Max torque (Nm)2 1800 Max flow (l/min) 123 1 Not in combination with max torque 2 at max pressure at 125 bar (1812 psi) Transport dimensions Weight approx. excl. options Width Length* Height* Length** Height** *feed in forward position **feed dumped on canopy

45/16" - 51/8" 51/4" - 6" 51/2" - 6" 3"⁄     3½"⁄4" 16'5" 148'

1330 lbf/ft 260 cfm

19000 kg 2500 mm 13600 mm 3110 mm 10650 mm 4075 mm

41900 lb 8'2" 44'7" 10'2" 34'11" 13'37"

Visit www.surfacedrilling.com for more information

35°

14° 36°

25°

25°

95°

2440 2140 8760

3030

ROC L6

2820 3550 5450

120

1900

Drilling in open pit mining

DTH DRILL RIG SPECIFICATION

CM 780D Technical data Recommended hole range Recommended Optional DTH hammer Drill tube diam. Drill tube length Hole depth, max.

115 -152 mm 85 -152 mm 102 - 127 mm 89-102 mm 4 m 30 m

Compressor Type Working pressure FAD

2-stage Rotary Screw 24 bar 350 psi 405 l/s 862 cfm

Engine Caterpillar Diesel Rating at 1800 rpm

CAT C13 Tier III Compliant 328 kW 440 HP

Fuel tank Total capacity

587 l

155 US gal.

Feed Feed length, total Travel length Feed extension Feed rate, max. Feed force, max.

6579 mm 4293 mm 1219 mm 0.76 m/s 43.6 kN

21'7" 14'1" 4' 149 ft/min 9800 lbf

The CM 780D is a high capacity down-the-hole crawler for drilling with 4”and 5” hammers in aggregate and limestone quarries or in volume mining operations. The simple direct-drive rotary head delivers plenty of torque, a benefit when drilling in poor ground conditions. The rugged CAT C13 Tier III engine delivers the required horsepower and is easy accessible for service.

Tramming Tramming speed, max. Traction force Hill climbing ability Track oscillation Ground clearance

3.2 km/h 125.4 kN 30° ± 10º 432 mm

2 mph 28192 lbf

Hydraulic rotation unit Max speed Torque max, drilling Max torque

0 - 80 rpm 4236 Nm 6100 Nm

3125 ft.lbf 4500 ft.lbf

Standard equipment

Transport dimensions Weight, excl. options Width Reaching shortest length Length Height Reaching lowest height Length Height

22200 kg 2570 mm

49000 lbs 8'5"

10680 mm 3300 mm

35'½" 10'8"

10820 mm 3070 mm

35'6" 10'1"

17"

Visit www.surfacedrilling.com for more information

8°

98.25

101.25

22°

90°

Mechanized pipe handling, Automatic throttle, Central Hydraulic system test port, Variable speed cooling fan control, Max engine rpm control, Tier III emission compliance, 2D electronic angle indicator, Feed extension, Dual pinning for L/R horizontal drilling, Water mist system preplumbed for tank, Preseparator, Dust collector, Retractable dust hood Thread greasing device, FOPS and ROPS operator safety cab, Cab airconditioning, Working lights, Back up alarm, Heavy duty tracks with full length rock guards, Track oscillation, Variable air volume control for collaring, DTH hammer lubricator device (pneumatic)

41⁄ 2" - 6" 33⁄3" - 6" 4" - 5" 3½" - 4" 13', 1½" 98.5 ft

90°

Optional Equipment

3D angle indicator, 3D angle indicator with speed and depth, Central lubrication system, Auxiliary winch for loading pipes, Hydraulic system test kit, Wrenches, Non-pressurized water mist tank 80 gal, Non-pressurized water mist tank 120 gal instead of DCT, Cold ambient kits, DTH hammer lubricator device (electric)

8° 90° 22°

30°

14°

90°

98.25 30°

Drilling in open pit mining

14°

101.25

121

DTH DRILL RIG SPECIFICATION

ROC L8 Technical data Recommended hole range COP 44/44Q COP 54 COP 54HD COP 64 COP 64HD Drill tube diam. Drill tube length Hole depth, max. Compressor Atlas Copco Working pressure, max. FAD Diesel Engine Caterpillar Rating at 2000 rpm Fuel tank Capacity

The total solution for drilling in quarries and open pit mines, the ROC L8 DTH crawler drillrig is designed for pre-splitting and large-scale production work. It has ample power to deliver high penetration rates and a rod handling capacity for hole depths up to 54 m.

Standard equipment

Air conditioning/heater, Tube handling system (capacity of 8 tubes), Reduced air pressure for collaring, Fuel sav- ing device, Two-speed traction motors, Dust collector and pre-separator, Feed extension, Heavy-duty tracks, Operator’s cabin (ROPS and FOPS approved), Atlas Copco electronic hole depth/inclination instrument, Break-out table, Retrac- table suction hood, Track chains with triple grouser pads, Hydraulic support leg

Optional equipment

Central lubrication system, Electric refuelling pump, Water mist systems, Track chains with single grouser pads, Hydraulic support leg, Heavy duty air intake filters for engine and compressor, Cold weather kits including engine heater, Heating system for cabin, Cab windows laminated, Cab windows tinted, Radio and CD player, Sun shades for cab windows, Electric heated operator’s seat 30°

110 -130 mm 134 -152 mm 140 -152 mm 156 -178 mm 165 -178 mm 89/102/ 114/140 mm 6 m 54 m

45/16" - 51/8" 51/4" - 6" 51/2" - 6" 61/8" - 7" 61/2" - 7" 3½"/4"/4½"/ 5½" 20' 177'

XRV 9 screw compressor 25 bar 363 psi 405 l/s 858 cfm CAT C13 Tier III Compliant 328 kW 440 HP 780 l

206 US gal.

Feed Feed length, total 11250 mm Travel length 8122 mm Feed extension 1150 mm Feed rate, max. 0.92 m/s Feed force, max. 30 kN Tractive pull, max. 40 kN Tramming Tramming speed, max. 3.4 km/h Traction force 120 kN Hill climbing ability 20° Track oscillation +10º -8° Ground clearance 405 mm Hydraulic rotation unit DHR 48H45 Max speed (rpm)1 112 Max torque (Nm)2 1800 Max flow (l/min) 123 DHR 48H56 Max speed (rpm)1 88 Max torque (Nm)2 2300 Max flow (l/min) 123 DHR 48H68 Max speed (rpm)1 56 Max torque (Nm)2 3600 Max flow (l/min) 123 260 cfm 1 Not in combination with max torque 2 at max pressure at 125 bar (1812 psi) Transport dimensions 20000 kg Weight approx excl. options Width 2500 mm Length 11250 mm Height 3995 mm

3'11" 26'8" 3'9" 180 ft/min 6744 lbf 8992 lbf 2.1 mph 26980 lbf 16"

1330 lbf/ft 260 cfm 1700 lbf/ft 260 cfm 2655 lbf/ft

44000 lbs 8'2" 36'11" 13'1"

30°

14° 36°

25°

25°

11250

2440 2140 ROC L8

3030

2820 1900

3550 5450 7000

122

Drilling in open pit mining

DTH DRILL RIG SPECIFICATION

ROC L8 30 Technical data

RHS 102 tube magazine, Engine monitoring and feed inclination, Hole depth instrument, Pre-separator and dust collector with automatic cleaning system, Operator’s ROPS and FOPS cab, Air conditioning, Window wipers, Triple grouser pads, Work lights, Gas spring operated canopy doors, Emergency stops

Optional equipment

Toe-hole drilling kit for short mast, Service winch, Thread spray lubrication, Cab heating system, Tinted cab windows, Laminated cab windows, Sun shade kit for cab, Electric heated operator’s seat, Reverse camera, Radio/CD, Canopy safety rails, Revolving light (BEACON), Engine monitoring with hole inclination/ depth instrument and laser receiver, Cold weather kits including diesel driven engine heater, Water mist fl ushing systems, Tropical/arctic/ synthetic hydraulic oils, Manual/automatic fi re suppression systems, Central lubrication system, Fast fi lling fuel system, Electric hydraulic oil fi lling system, Hydraulic support leg, Canopy service lamps, RC (reverse circulation) kit.

Compressor Atlas Copco Working pressure FAD

XRV 9 screw compressor 30 bar 435 psi 470 l/s 995 cfm

Engine Caterpillar Diesel Rating at 2000rpm

CAT C15 Tier III Compliant 402 kW 539 HP

Fuel tank Total Capacity

760 l

201 US gal.

Feed Feed length, long mast Feed length, short mast Travel length, long mast Travel length, short mast Feed extension Feed rate, max. Feed force, max.

11564 mm 9266 mm 7540 mm 5400 mm 1150 mm 0.9 m/s 40 kN

38' 30'4" 25' 17'7" 3'9" 177 ft/min 8992 lbf

Tramming Tramming speed, max. Traction force Hill climbing ability Track oscillation Ground clearance

1.7/3.5 km/h 124/49 kN 20° +10º - 8º 405 mm

1.2/2.2 mph 27876/11016 lbf

45/16" - 51/8" 51/4" - 6" 51/2" - 6" 61/8" - 8" 61/2" - 8" 3½"/4"/4½"/5½" 20 ft 16.4 ft 177 ft 148 ft

16"

Hydraulic rotation unit DHR 48H45 Max speed 0 - 136 rpm Max torque 2070 Nm

1527 lbf/ft

Hydraulic rotation unit DHR 48H56 Max speed 0 - 107 rpm Max torque 2630 Nm

1940 lbf/ft

Hydraulic rotation unit DHR 48H68/DHR 48RC Max speed 0 - 68 rpm Max torque 4120 Nm

3039 lbf/ft

Transport dimensions Weight, excl. options Width Length Height

54000 lbs 8'2" 40' 11'6"

24500 kg 2500 mm 12200 mm 3500 mm

Short feed

A

B

Drilling in open pit mining

2140

2140

2440

25º

13º

21º

Long feed

2440

Standard equipment

110 -130 mm 134 -152 mm 140 -152 mm 156 -203 mm 165 -203 mm 89/102/ 114/140 mm 6 m 5 m 54 m 45 m

25º

This new version of the proven ROC L series of downthe-hole crawler drills offers extended performance through increased operating pressure and a new genius cylinder feed system. Like the well proven ROC L8 it’s well suited for large-scale production work, pre-split operations, RC-in pit grade control in surface mining operations and large scale quarry operations.

Recommended hole range COP 44/44Q COP 54 COP 54HD COP 64 COP 64HD Drill tube diam. Drill tube length, long mast Drill tube length, short mast Hole Depth, max. Hole Depth, optional

A Long feed 582 Short feed 1040 B Long feed 2277 Short feed 2659

123

DTH HAMMER SPECIFICATIONS

Air consumption/Working pressure (cfm) 2000

(l/s) 900

Air consumption

800 1500

Hammer types

700

Type

600 1000

COP COP COP COP COP

500 400 300

500

Std

34 44 54 54 GE 64 G

HD

Slim*

       

200

 

* Reduced hammer OD

100 0

0 10

15 200

150

20 250

25

300

350

30 400

(bar)

450 (psi)

Working pressure COP 34

COP 44

COP 54

COP 54 GOLD EXPRESS

COP 64 GOLD

Technical data Hammer

COP 34

COP 44



COP 54

COP 54 Gold Express

COP 64 Gold

Length excl. thread

954 mm

37.55 in

958 mm

37.72 in

1069 mm

42.08 in

1119 mm

44.1 in

1163 mm

45.78 in

External diameter

83.5 mm

3.28 in

98 mm

3.86 in

120 mm

4.72 in

120 mm

4.72 in

142 mm

5.59 in

External diameter HD

126 mm

4.96 in

126 mm

4.96 in

146 mm

5.75 in

Hammer weight

57 kg

126 lbs

66 kg

145 lbs

96 kg

212 lbs

Hammer weight HD

67 kg

148 lbs

76 kg

167 lbs

109 kg

241 lbs

27 kg

60 lbs

38 kg

84 lbs

Piston diameter

68 mm

2.67 in

78 mm

3.07 in

100 mm

3.93 in

100 mm

3.93 in

120 mm

4.72 in

Piston weight

4.8 kg

10.7 lbs

7.1 kg

16 lbs

12.5 kg

28 lbs

15 kg

33 lbs

20.5 kg

45 lbs

Recommended bit size

92-105 mm

35/8-41/8 in

110-125 mm

45/16++-5 in

134-152 mm 51/4-6 in

134-152 mm 5.3-6 in

156-178 mm 61/8-7 in

140-152 mm 51/4-6 in

140-152 mm 5.5-6 in

165-178

152-178 mm 6-7 in

Rec. bit size HD

Rec. bit size Slim

130-152 mm 5.1-6.0 in

Bit shank

COP 34

IR DHD340

IR DHD350

IR QL 50

IR QL 60

Top sub thread

23/8" API Reg

23/8" API Reg

23/8" API Reg

31/2" API Reg

31/2" API Reg

Optional thread connection

31/2" API Reg

27/8" API Reg

31/2" API IF

Wrench flat 23/8" API Reg

65 mm

2.6 in

95 mm

3.7 in

65 mm

2.6 in

65 mm

2.6 in

27/8" API Reg

65 mm

2.6 in

31/2" API Reg

95 mm

3.7 in

102 mm

31/2" API Reg (HD)

102 mm

4.0 in

102 mm

4.0 in

102 mm

Feed force Feed force, normal

3-12 kN 6 kN

700-2500 lbs 1300 lbs

5-15 kN  10 kN

1100-3300 lbs 2200 lbs

6-17 kN  12 kN

1300-3700 lbs 6-19 kN  2600 lbs 14 kN

1300-4100 lbs 7-20 kN 2600 lbs 14 kN

Working pressure

6-25  bar

87-360 psi

6-25 bar

87-360 psi

6-25  bar

87-360 psi

87-360 psi

Rotation speed

30-90 r/min

25-80 r/min

20-70 r/min

6-25  bar

20-70 r/min

61/2-7 in

4.0 in 4.0 in 1600-4400 lbs 3100 lbs

12-30 bar 174-430 psi 25-60 r/min

Standard design – Ideal for water well drilling, blast hole drilling and civil engineering projects. HD design – Designed for abrasive and demanding applications. The HD hammer features a larger overall diameter, in turn allowing for thicker walls and, ultimately, a longer service life. It’s also equipped with reversing back-out buttons, protecting the top sub from wear. Slim design – The Slim version is designed for non to medium-abrasive formations, using a smaller bit diameter than recommended for the standard hammer OD. The Slim design allows an oversized hammer to drill the hole, thereby optimizing performance.

124

Drilling in open pit mining

DTH HAMMER SPECIFICATIONS

ROC F6 Rotation unit

1

Adapter

Crossover

Drill tubes

DTH Hammer

Bit

No wrench flats

L = 4 000 mm

No wrench flats

API 2 3/8” Reg Pin x Box L = 305 mm

OD = 76 mm

API 2 3/8” Reg Wall = 6.3 mm

Not needed

COP 34, API 2 3/8” Reg

95-105 mm

API 2 3/8” Reg Pin x Box L = 305 mm

OD = 89 mm

API 2 3/8” Reg Wall = 6.3 mm

Not needed

COP 44, API 2 3/8” Reg

110-130 mm

DHR 45 H-1 API 2 3/8” Reg Box (*)

NB

(*) Floating adapter should be chosen to prevent fast wear out of threads and cradle wear parts For further info on bit designs and sizes, see our Secoroc Rock Drilling Tools

ROC L6 Rotation unit

Adapter

Crossover

Drill tubes

No wrench flats

L = 5 000 mm

No wrench flats

API 2 3/8” Reg Pin x Box L = 305 mm

OD = 76 mm

API 2 3/8” Reg Wall = 6.3 mm

Not needed

Not needed 1

DHR 48 H 45-1 API 2 3/8” Reg Box

API 2 3/8” Reg Pin x Box L = 305 mm

D = 89 mm

API 2 3/8” Reg Wall = 6.3 mm

API 2 7/8” x 2 3/8” Reg L = 140 mm (**) API 2 3/8” x 2 7/8” Reg Pin x Box L = 305 mm

OD = 102 mm

API 2 7/8” Reg Wall = 6.3 mm API 2 7/8” x 3 1/2” Reg L = 160 mm

2

3

DHR 45 H-1 DHR 45 H-2 API 2 3/8” Reg Box (*) (***) DHR 48 H 45-2 (*)

NB

DTH Hammer

Bit

COP 34, API 2 3/8” Reg

95-105 mm

COP 44, API 2 3/8” Reg

110-130 mm

COP 54, API 2 3/8” Reg

134-140 mm

COP 54, API 2 3/8” Reg

134-152 mm

COP 54HD, API 2 3/8” Reg

140-152 mm

COP 54, API 3 1/2” Reg

134-152 mm

COP 54HD, API 3 1/2” Reg

140-152 mm

(*) Floating adapter should be chosen to prevent fast wear out of threads and cradle wear parts (**) Hammer thread is potentially a weak point. Highly recommended to change top sub to 3 1/2” API (***) Only for customers who own ROC 830s or ROC F6s to standardize in same rotation unit For further info on bit designs and sizes, see our Secoroc Rock Drilling Tools Catalogue

ROC L8 Rotation unit

1

2

DHR 48 H 45-1 DHR 48 H 45-2 API 2 3/8” Reg Box (*)

DHR 48 H 56-1 DHR 48 H 56-2 API 2 3/8” Reg Box (*)

DHR 48 H 56-3 DHR 48 H 56-6 API 3 1/2” Reg Box (*)

Adapter

Crossover

Drill tubes

No wrench flats

L = 6 000 mm

No wrench flats

API 2 3/8” Reg Pin x Box L = 305 mm

OD = 89 mm Wall = 6.3 mm

API 2 3/8” Reg

API 2 3/8” x 2 7/8” Reg Pin x Box L = 305 mm

OD = 102 mm Wall = 6.3 mm

API 2 7/8” Reg

API 2 3/8” x 2 7/8” Reg Pin x Box L = 305 mm (**)

Not needed

API 2 7/8” x 2 3/8” Reg L = 140 mm (***) API 2 7/8” x 3 1/2” Reg L = 160 mm

OD = 102 mm Wall = 6.3 mm

API 2 7/8” Reg

OD = 114 mm Wall = 6.3 mm

API 3 1/2” Reg

DHR 48 H 68-3 DHR 48 H 68-6 API 3 1/2” Reg Box (*)

Drilling in open pit mining

COP 44, API 2 3/8” Reg

Bit 110-130 mm

COP 54, API 2 3/8” Reg

134-140 mm

COP 54, API 2 3/8” Reg

134-152 mm

COP 54HD, API 2 3/8” Reg

140-152 mm

COP 54, API 3 1/2” Reg

134-152 mm

COP 54HD, API 3 1/2” Reg

140-152 mm

COP 64 Gold, API 3 1/2” Reg

156-171 mm

COP 64 Gold HD, API 3 1/2” Reg

165-171 mm

API 3 1/2” x 2 7/8” Reg Pin x Box L = 305 mm

API 3 1/2” Reg Pin x Box L = 305 mm 3

DTH Hammer

API 3 1/2” Reg Pin x Box L = 305 mm

NB

Not needed

(*) Floating adapter should be chosen to prevent fast wear out of threads and cradle wear parts (**) This alternative is NOT highly recommended as the DHR thread is a weak point (***) Hammer thread is potentially a weak point. Highly recommended to change top sub to 3 1/2” API For further info on bit designs and sizes, see our Secoroc Rock Drilling Tools Catalogue

125

DTH ROTATION UNITS

Rotation units for DTH drilling

DHR 45A

DHR 48H

DHR series

Hole diameter range 70-254 mm, drilling torque up to 5100 Nm The Atlas Copco DHR series of rotation units includes a total of 7 airpowered and 12 hydraulically-powered standard motors designed for longer life, superior wear resistance, and enhanced output. All are equipped with both fixed and moving adapters for all common types and dimensions of thread. Air-powered versions in the DHR series have powerful vane motors, to ensure top-quality operating reliability and wear resistance. The torque, delivered at a working pressure of 6 bar, is sufficient for maximum drill capacity, and can be easily increased to 8 bar for greater torque without any risk of overloading. Both rotation speed and direction can easily be changed. The vane motor is integrated with a long-life, well-tested planetary gear.

DHR 48RC

The hydraulically-operated DHR versions are equipped with reliable, longlife motors of a type for which planetary gear is unnecessary. Normal working torque is obtained even at a very modest hydraulic pressure. The potential working pressure, however, is much greater, offering a good margin for more demanding work situations. Engine speed and rotation direction are easy to set on all motors, and the superior design gives both quiet operation and minimal maintenance. There are two well-proven sizes of reduction gear with various gear combinations to suit all DHR series motor versions. They are extremely strong, and designed for simple and easy mounting. The DHR 48RC version is intended for reverse circulation drilling on ROC L8. It is designed to fit the drill string components as simple hose connection and underneath air swivel from Metzke Engineering, Australia.

Technical data, air powered Type Length1 (mm) Width cradle (mm) Height (mm) Height from base to centre of spindle (mm) Weight1 (kg) Air connection DTH hammer (in) Drive motors Air connection motor (in)

DHR 45A 870/1026 255 333

DHR 56A 951/1120 270 365

126 126/144 2 1 3/4

138 235/275 2 2 3/4

Torque Nm

Air requirement l/s

4000

6 bar

400

8 bar DHR 56A

3000

DHR 45A

300

2000

200

1000

100

with fixed adapter/floating adapter

1

0

Operative data, hydraulically powered rotation units Type Length1, (mm) Weights1, (kg) Drill tube connection API Reg Female Drive motors (qty) Drilling performance Torque, max (Nm)2 Press drop, max (bar) Speed, max (rpm)3 Flow, max (l/min)

DHR 45H 685/842 111/124

DHR 48H45 528/882 163/239

DHR 48H56 534/888 164/240

DHR 48H68 550/904 166/242

2 /8”

2 /8”

1

2

2 /8” 3½” 2

2 /8” 3½” 2

2200 175 80 75

3000 210 136 150

3900 210 107 150

5100 175 68 150

3

3

3

With fixed adapter/floating adapter With mineral oil. For other oils ask for information 3 Not in combination with max torque 1 2

126

3

20

40

60

80

100

rpm

Adapter type/thread DHR 48RC 696/178/-

Rotation Units Hydraulically Adapter Powered type/thread

DHR 45H-1 DHR 45H-2 4”Metzke DHR 48H45-1 Long pin Male DHR 48H45-2 2 DHR 48H56-1 DHR 48H56-2 5100 DHR 48H56-3 175 DHR 48H56-6 68 DHR 48H68-1 150 DHR 48H68-2 DHR 48H68-3 DHR 48H68-6 DHR 48RC

Recommended for DTH Hammer

Floating API 23/8" Reg Box Fixed API 23/8" Reg Box Floating API 23/8" Reg Box Fixed API 23/8" Reg Box Floating API 23/8" Reg Box Fixed API 23/8" Reg Box Floating API 31/2" Reg Box Fixed API 31/2" Reg Box Floating API 22/3" Reg Box Fixed API 23/8" Reg Box Floating API 31/2" Reg Box Fixed API 31/2" Reg Box Fixed 4" Metzke Long pin Male

3"- 4"- 5" 3"- 4"- 5" 3"- 4"- 5" 3"- 4"- 5" 4"- 5" 4"- 5" 5"- 6" 5"- 6" 4"- 5" 4"- 5" 6"- 8" 6"- 8" RC-hammer

DRILLING IN OPEN PIT MINING

ROTARY DRILL RIGS

Large Blasthole Drills

Atlas Copco offers a wide range of large drills for production blast hole drilling in open pit mining. There are a variety of alternatives, including crawler or custom mounted carriers, single or multi pass versions, diesel or electric prime movers. The range covers hole diameters from 4½ up to 16¼ inches. (114 – 413 mm).

Technical data

Installed Power Pulldown force Maximum Hole Diameter Hp (kW) lbf. (kN) inch. (mm) DM25SP DM30 DM45 DM50 DML DMLSP T4BH PV271 PV275 DM-M3 DM-H2 PV351

360 - 460 425 - 525 425 - 525 425 - 525 525 - 765 525 - 765 525 - 760 760 760 630 - 950 600 - 950 1,650

(270-340) 46,000 (315-390) 30,000 (315-390) 45,000 (315-390) 45,000 (390-570) 60,000 (390-570) 60,000 (390-565) 30,000 (565) 75,000 (565) 75,000 (470-705) 90,000 (445-705) 110,000 (1230) 125,000

(205)   63⁄4 (135)   63⁄4 (200)   77⁄8 (200)   77⁄8 (270)   9 (270)   9 (135) 10 (335) 105⁄8 (335) 105⁄8 (400) 121⁄4 (490) 133⁄8 (560) 161⁄4

(171) (171) (200) (200) (229) (229) (254) (270) (270) (311) (340) (413)

Visit www.cmt.atlascopco.com/ads/ for more information

Drilling in open pit mining

127

ROTARY DRILL RIG SPECIFICATION

DM30 Main specifications

The DM30 represents an ideal combination of versatility, economy, and power in rotary blasthole drills. The DM30 is designed for quarrying and small mining applications. This versatile drill can be easily loaded onto a trailer and moved from one location to another. Strong and powerful, the high-strength cable feed system absorbs drilling shock, improves rotary head life and minimizes inventory requirements. The 136 HP/101 kW spur gear head provides high torque for maximum drilling performance, smooth rod handling, and a powerful impact breakout system. With a precision controlled, pressure balanced cylinder feed system, the DM30 has a 30,000 lb/13,608 kg bit weight and a 10,000 lb/4,536 kg pullback capacity.

Standard equipment

Thermal insulated, sound-attenuated cab, Dust collector, Dust hood w/skirting, Halogen night light pkg, Aux. hoist, Engine and air compressor intake filters, Remote tower pinning, Carousel, Remote hydraulic fork chuck for breakout, Hydraulic aux. chain wrench, 230-gal (870L) fuel tank, Leveleing jacks, 68,000 lb (30,845 kg) GVW rated undercarriage, Oscillation yoke, Service walkways w/railing, Back-up alarm, DHD lube, Central lube manifold, Centralizer, Hammer split and split bushings, Lifting bail, Grease gun, Blow gun w/hose, O-ring kit, windshield wipers/washers

Optional equipment

A variety of options is available to meet your drilling needs including (but not limited to): floating spindle sub, water injection w/arctic fox, Automatic and manual lube systems, central service system, diesel-fired preheater, battery and engine oil pan heater, Thunderbird DEI depth and rate of penetration monitor, tramming foot pedal brake, torque limit control, inclinometer.

128

Recommended hole range Nominal Hole Size 127 - 171 mm 5" - 63/4" Hole depth, max. STD 27.4 m 90' Hole depth, max. Optional 47.5 150' Pipe length 9.14 m 30 ft Feed system Hydraulic pulldown force 133 kN 30.000 lbf Hydraulic pullback force 44.5 kN 10.000 lbf Fast feed/retract speed 0 - 30.5 m/min 0 - 100 ft/min 0 - 85 m/min 0 - 280 ft/min Rotary head, two-stage, spur gear Spindle thread Size 101.5 mm 4" API IF Rotation motors 101 kW 136 HP Torque, variable 7.322 Nm 5.400 lbf/ft Tower Rod changing (2 or 4 pipe) 9.1 m/each pipe 30 ft/each Auxiliary hoist, (Hyd. motor) 1.134 kg 2.500 lb Tower raising & lowering 2 hydraulic cylinders Mainframe Leveleing jacks 18.598 kg 41.000 lb Jack Pad diameter 457 mm 18" Jack Pad Area 1.642 sq. cm 254.5" sq. Undercarriage Model CAT 320, AC GT 2000 Track length 4.44 m 14 ft 7 in Track width 2.9 m   9 ft 5 in Powerpack High pressure configuration at 350 psi 900 cfm 25.5 m3/min at 2413 kPa Diesel engine options EPA Tier 3 Caterpillar C-15 Rating at 1800 rpm 540 HP 403 kW Cummins QSX15 560 HP Rating at 1800 rpm 418 kW Low pressure configuration 900 cfm at 110 psi at 758 kPa 25.5 m3/min Diesel engine options EPA Tier 3 Caterpillar C-15 Rating at 1800 rpm 475 HP 354 kW Cummins QSX15 425 HP Rating at 1800 rpm 336 kW Cooling system Cooling capacity 52 ºC 125 ºF ambient Fuel capacity 871 l 230 gal Hydraulic system Main pumps, piston pumps 197 l/min 52 gal/min Vane Pumps stage 1 133 l/min 35 gal/min Vane Pumps stage 2 64 l/min 17 gal/min Transport dimensions Weight (approx. excl. options) 28.121 kg 60,000 lbs Width shipping 2.9 m 113"        operational 3.6 m 142" Length tower up 7.4 m 292" tower down 12.9 m 506" Height tower up 13.5 m 532" tower down 4.4 m 174" Rock drilling tools Hole range 127 - 171 mm 5" - 63⁄4" COP 44 110 - 130 mm 43⁄8" - 5" COP 54 134 - 152 mm 5¼" - 6" QL 40 105 - 130 mm 4" - 5" QL 50 130 - 152 mm 5" - 6" QL 60 153 - 171 mm 6" - 63⁄4" Bit connection 89 mm 3½" Tricone bits 121 - 171 mm 43⁄4" - 63⁄4" Secoroc Duralloy bit sub adaptor can be used with: Pipe thread (pin end) 89 mm 31/2" BECO 200 mm or 27/8" API Bit thread (box end) 89 mm 31/2" BECO 200 mm or 27/8" AP

Drilling in open pit mining

ROTARY DRILL RIG SPECIFICATION

DM45 Main specifications

The DM45 is one of a family of drills designed to offer the ideal combination of efficiency, economy, and power in rotary blasthole drills. The standard DM45 utilizes a diesel engine to drive the air compressor and hydraulic system. Operation of the drill is performed using electric over hydraulic controllers ergonomically located so that the operator faces the drill centralizer while drilling. Both high pressure and low pressure models are available to fit your drilling needs.

Standard equipment

Insulated, FOPS, Sound-attenuated cab, Dust collector, Dust hood w/skirting, Halogen night light pkg, Aux. hoist, Engine and air compressor intake filters, Remote tower pinning, Carousel, Sliding hydraulic fork, Hydraulic aux. chain wrench, 1438 l/380-gal fuel tank, Leveleing jacks, 36,287 kg/80,000 lb GVW rated undercarriage, Oscillation yoke, Service walkways w/railing, No-bump rod changer, Back-up alarm, Jack up indicator lights, Rod support arm, Ether injection, Central lube manifold, Centralizer bushing, Lifting bail, Spindle sub, Blow gun, Manuals, Wipers/washers, Battery select master switch.

Optional equipment

A variety of options is available to meet your drilling needs including (but not limited to): Floating spindle sub, Language name plates, Water injection, 680 gal fuel tank, Auto lube system, Wiggins central service and fast fuel systems, Diesel-fired preheater, 240 V AC cold weather pkg, Variety of Aquila electronic monitoring systems, Thunderbird DEI depth and rate of penetration system monitor, Battery equalizer/converter, Tow hooks, Inclinometer, Torque limit control, Sunshades, 1070 cfm HP and 1050 cfm LP

Drilling in open pit mining

Recommended hole range Nominal hole size 114 - 178 mm 4½" - 7" Hole depth, max. 27 - 53 m 90 - 175' Pipe length 9.14 m 30 ft Feed system Hydraulic pulldown force 200 kN 45.000 lbf Hydraulic pullback force 98 kN 22.000 lbf Fast feed/retract speed 0 - 44.5 m/min 0 - 146 ft/min 0 - 62.48 m/min 0 - 205 ft/min Rotary Head, two-stage, spur gear 4-1/2" OD Drill pipe size 114.3 mm Spindle thread size 88.9 mm 3-1/2" API Reg Rotation motors 82 kW 110 HP Torque, variable (Nm) 12202 Nm 9.000 lbf/ft Tower 9.1 m/each pipe 30 ft/each Rod changing (7 pipe change) Auxiliary hoist, (hyd. motor) 1.134 kg 2.500 lb Tower raising & lowering 2 hydraulic cylinders Mainframe 26.717 kg 58.900 lb Leveleing jacks Jack pad diameter 762 mm 30 in Jack pad area 4560 cm sq 06.8"sq Undercarriage Model Atlas Copco branded tracks Track length 4673 mm 184 in 23.6 in Track width 600 mm Powerpack High pressure configuration at 350 psi 900 cfm at 2413 kPa 25.5 m3/min Diesel engine options EPA Tier 3 Caterpillar C-15 Rating at 1800 rpm 403 kW 540 HP Cummins QSX15 560 HP Rating at 1800 rpm 418 kW Low pressure configuration at 110 psi 900 cfm at 758 kPa 25.5 m3/min Diesel engine options EPA Tier 3 Caterpillar C-15 Rating at 1800 rpm 354 kW 475 LP Cummins QSX15 425 LP Rating at 1800 rpm 336 kW Cooling system Cooling capacity 51.6 ºC 125 ºF Fuel capacity 852 l 225 gal Hydraulic system Main pumps, piston pumps 268 l/min 71 gal/min Vane pumps stage 1 158 l/min 42 gal/min Vane pumps stage 2 83.3 l/min 22 gal/min Transport dimensions 60.000 lbs Weight (approx. excl. options) 28.121 kg Width 3.6 m 142" Length 13.3 m 43'7" Height 4.4 m 174" Rock drilling t ools Hole range 114 - 200 mm 4½" - 77⁄8" Bit connection 76 - 140 mm 3 - 51/2" COP 44 110 - 130 mm 43⁄8" - 5" COP 54 134 - 152 mm 5¼" - 6" QL 40 105 - 130 mm 4" - 6" QL 50 130 - 152 mm 43⁄8" - 6" QL 60 152 - 171 mm 6" - 63⁄4” Tricone bits 149 - 200 mm 57⁄8" - 77⁄8" Secoroc Duralloy bit sub adaptor can be used with: Pipe thread (pin end) 89, 101, 114 mm 31/2, 4, 41/2" BECO 89 mm or 31/2" API Bit thread (box end) 89, 101, 114 mm 31/2, 4, 41/2" BECO 89 mm or 31/2" API

129

ROTARY DRILL RIG SPECIFICATION

T4BH Main specifications

With a multitude of configurations from which to choose, the T4BH truck-mounted, rotary blasthole drill meets the tough challenges of the aggregate and construction industries. This powerful, mobile drill incorporates a comfortable, FOPs cab that provides the operator a non-obstructed view of the drill table and easy access to the drill controls. Fast, efficient drill pipe handling is accomplished with the carousel-type pipe changer. The high speed/high torque rotary head delivers the fastest drill rates in this class of drill, while consistently delivering up to 13607 kg/30,000 lb. of force to depths of 45.7 m/ 150 ft. Angle drilling is optional.

Standard equipment

Remote tower pinning, Gear indexing carousel, Sliding fork, Aux. chain wrench, 852 l/225 gal fuel tank, Custom carrier, Ether injection, Back-up larm, Centralizer bushing, Hoist plug, Spindle sub, Manuals.

Optional equipment

A variety of options is available to meet your drilling needs including (but not limited to): Angle drilling pkg, Torque limit control, Central lube manifold, 454 l/120 gallon aux. Fuel tank, Water injection, Remote propel from cab, Drilling efficiency indicator, Cold weather starting aid, Floating spindle sub, 1070 cfm HP and 1250 cfm HP

130

Recommended hole range Nominal hole size 190.5 - 254 mm 7½" - 10" Hole depth, max. 46 m 150' Pipe length 7.6 or 9.14 m 25 or 30 ft Feed system Hydraulic pulldown force 164.6 kN 37.000 lbf Hydraulic pullback force 73.4 kN 16.500 lbf Fast feed/retract speed 14.6 m/min 48 ft/min 33.5 m/min 110 ft/min Rotary head, two-stage, spur gear Spindle thread size 101.6 or 102 mm 4" API IF Rotation motors 82 kW 110 HP Tourque, variable 8.135 Nm 6.000 lbf/ft Tower 7.6 m/each pipe 25 ft/each Rod changing (7 pipe change) Auxiliary hoist, (hyd. motor) 1.134 kg 2.500 lb Tower raising & lowering 2 hydraulic cylinders Mainframe 26.717 kg 58.900 lb Leveleing jacks Jack pad diameter 457 mm 18" Truck Model Crane Carrier Truck engine CAT C11 227 kW 305 HP Front axle capacity 10.886 kg 24.000 lg Rear axle capacity 20.412 kg 45.000 lb Transmission: Fuller RTO-11908LL 10 speed forward, 3 speed reverse Powerpack High pressure configuration at 350 psi 900 cfm at 2413 kPa 25.5 m3/min Diesel Engine Options EPA Tier 3 Cummins QSK15 Rating at 1800 rpm 418 kW 560 HP Cooling system Cooling capacity 51.6 ºC 125 ºF Fuel capacity 852 l 225 gal Hydraulic system Main pumps, piston pumps 268 l/min 71 gal/min Vane Pumps stage 1 158 l/min 42 gal/min Vane Pumps stage 2 83.3 l/min 22 gal/min Transport dimensions 58.000 lbs Weight (approx. excl. options) 26.308 kg Width⁄ 2.4 m 8 ft Length 10.7 m 35 ft Height 4.12 m 13 ft 6 in Rock drilling tools Hole range 165 - 228 mm 61⁄2" - 9" COP 44 110 - 130 mm 43⁄8" - 5" COP 54 134 - 152 mm 5¼" - 6" COP 64 156 - 171 mm 6 - 63⁄4" QL 40 105 - 130 mm 4" - 5" QL 50 130 - 152 mm 5" - 6" QL 60 152 - 171 mm 6" - 63⁄4" QL 80 203 - 228 mm 8" - 9" Bit connection 127 - 218 mm 5 - 85⁄8" Tricone bits 149 - 200 mm 57⁄8" - 77⁄8" Secoroc Duralloy bit sub adaptor can be used with: Pipe thread (pin end) 89, 101 mm 31/2, 4" BECO 71, 89 mm or 27/8, 31/2" API Bit thread (box end) 89 mm 31/2" BECO 71, 89 mm or 27/8, 31/2" API

Drilling in open pit mining

SECOROC TRICONE BITS

Secoroc Tricone Bits Air Water Separator or Back Flow Valve

Third Digit – Designates Bit’s Bearing Features: Lock Ring Air Tube

Pin Connection

Nozzle Pin Shoulder

Air Passage to Bearing

Nozzle Nail Lock Lug Shirttail Inserts

Ball Retaining Pin

The underlined types are the main bearing types produced by Atlas Copco BHMT, Inc.

Ball Retaining Pin Weld

Example: IADC 6-3-2

Shirttail Hardfacing

Gauge Bevel Inserts

Outer Roller Bearing

Gauge Inserts

Ball Bearing

Cutter Cone Air Exit Slot Nose Inserts

1 – Roller Bearing 2 – Roller Bearing Air-Cooled 3 – Roller Bearing with Gage Bevel Inserts 4 – Sealed Roller Bearing 5 – Sealed Roller Bearing with Gauge Bevel Insets 6 – Sealed Friction Bearing 7 – Sealed Friction Bearing with Gauge Bevel Inserts 8 – Special 9 – Special

Cone (L) and Journal (R) Thrust Buttons

Inner Roller Bearing

Nomenclature Atlas Copco BHMT Inc. uses the IADC code along with the Product Line and added feature in the bit’s nomenclature to help describe the bit.

International Association, Drilling Contractors Code: The IADC Code is a three numbered system to classify the hardness and type for all roller cone rock bits. First Digit – Identifies the Bit Type and Major Hardness class: 1 – Steel Tooth for soft formations 2 – Steel Tooth for medium formations 3 – Steel Tooth for hard formations 4 – Insert for soft formations 5 – Insert for soft/medium formations 6 – Insert for medium/hard formations 7 – Insert for hard formations 8 – Insert for extremely hard formations

This is a Medium/Hard Air-Cooled Roller Bearing.

Example: 12¼ MAG53CA 12¼ MAG 53 C A

Diameter, inches Product Line First two digits of the IADC code (Rock Class ‘5’, subclass ‘3’) Insert Type (Conical Inserts) Full Armoured Lug (Nevada Package)

Product Lines:

• MAG – Maximum Active Gauge use in soft/medium material. • MAG II – Second generation MAG bits featuring enhanced erosion resistance features and new bearing geometries. • HD – Hard Drilling. Medium hard to hard formation bits. • HD+ – New generation Hard Drilling rotary bits used in medium hard to hard formations, with new carbide grades, aggressive cutting structures, and enhanced bearings. • BH – Standard Product.

Insert Type:

• C – Conical • G – Ogive • S – Super Scoop *Chisels and Ovoids are standard inserts and do not have suffixes

The underlined types are the main rock bit types produced by Atlas Copco BHMT, Inc. This range of rock bits will cover EVERY application of a rotary rock bit.

Second Digit – Designates the Hardness Subclass of Major Hardness class. This ranges from 1 to 4, where 1 is classified as the softest subclass and 4 is the hardest subclass. Drilling in open pit mining

131

SECOROC TRICONE BITS

Tungsten Carbide bit selection and operation Five basic classifications of Atlas Copco BHMT, Inc. rock bits are available for blast hole drilling. The modifications in cutting structure design from series to series are: 1. The spacing of inserts (or teeth) is greatest for the softer or weaker formations and decreases as the formation hardness increases. 2. The number of rows of inserts and/or the total number of inserts per bit is increased as formation hardness increases. 3. The groove depth and amount of intermesh is decreased as formation hardness increases. 4. The insert projection above the cone shell is greatest for the softer formations and is decreased as the formation hardness increases.

40 Series

The 40 series bits are typically characterized by large diameter widely spaced super scoop, chisel or conical inserts. This configuration promotes maximum penetration rates in softer formations that have a tendency to stick and ball up the cutting structure.

Applications Soft formations such as shale, siltstone, soft limestone and alluvials. Suggested Operating Parameters:

Weight on bit –1,000 to 5,000 lb/inch of diameter Rotation speed – 50 to 150 rpm

50 Series

The 50 series bits are typically characterized by more densely spaced chisel or conical inserts. This configuration promotes maximum penetration rates in soft/medium formations that are fractured or have varying degrees of hardness.

Applications

Soft/medium formations such as sandstone, shale, granite and some marble.

60 Series

The 60 series bits are typically characterized by more densely spaced, shorter projecting chisel, conical or ogive inserts. This configuration promotes maximum penetration rates in medium/hard formations.

Applications

Medium/ hard formations such as hard limestone, hard shale, basalt and quartzite.

Suggested Operating Parameters: Weight on bit – 4,000 to 7,000 lb/inch of diameter Rotation speed – 50 to 120 rpm

70 Series

The 70 series bits are typically characterized by a densely spaced, shorter projecting conical or ogive inserts with a conical or ovoid gauge insert. This configuration promotes maximum penetration rates in hard formations.

Applications

Hard formations taconite, banded iron and quartzite.

Suggested Operating Parameters: Weight on bit – 4,000 to 8,000 lb/inch of diameter Rotation speed – 50 to 90 rpm

80 Series

The 80 series bits are typically characterized by very densely spaced, short projecting ovoid inserts. This configuration promotes maximum penetration rates in extremely hard formations.

Applications Extremely

hard formations such as chert, hematite ore and quartzite.

Suggested Operating Parameters:

Suggested Operating Parameters:

Weight on Bit – 3,000 to 6,500 lb/inch of diameter Rotation Speed – 50 to 150 rpm

Weight on bit – 6,000 to 9,000 lb/inch of diameter Rotation speed – 40 to 80 rpm

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Drilling in open pit mining

secoroc grinding

Grinding Grinding machines Grinding machine

Button Bits

DTH/COPROD bits

recommended can be used *Can be used for ODEX pilot bits and reamer Reaming bits

X-type bits

Cross-type bits

Integrals

Grind Matic BQ2 Grind Matic Jazz Grind Matic Manual B Grind Matic HG Grind Matic BQ2-DTH Grind Matic Manual B-DTH* Grind Matic X Grind matic Swing Grind Matic Senior

Grind Matic BQ2

Note:

Drilling in open pit mining

Grind Matic Jazz Rig-mounted, semiautomatic grinding machine for tapered, threaded, DTH and COPROD bits. Grind Matic Jazz, standard 9500-4100 incl. main bit holder for threaded bits Grind Matic Jazz, DTH 9500-4300 incl. main bit holder for DTH / COPROD bits Grinding capacity Max. distance 250 mm (10") Max. diameter of drill bit 254 mm (10") Min. diameter of drill bit 35 mm (1 ³⁄8") Min. distance between buttons 3,5 mm (9⁄64") Technical specifications Air pressure, maximum 7 bar (102 psi) Air pressure, minimum 6 bar (87 psi) Air consumption 25 l/sec Speed, spindle 15 000 rpm 1 kW Output, spindle motor Voltage 24 V Coolant container 3 liter Weight, exclusive of packing 90 kg Dimension 800 x 500 x 700 mm (31.5 x 20 x 27.5 in.) Accessories included in delivery Product code Box wrench, 11 mm 9500-4425 Box wrench, 16 mm 9500-4426 Protective eyewear 9500-1967 Grinding gauge 9500-9104 Operators instructions/ Spare parts list 9852 1490 01 Optional accessories Anti-freeze kit 9500-4315 Main bit holder for DTH/ COPROD bits 9500-4268 9500-4214 Main bit holder for threaded bits Mounting bracket for Atlas Copco drill rig - with cabin 9500-4388 - without cabin 9500-4456 3-leg stand 9500-4450 Centering tool 9500-4465 NOTE! Grind Matic Jazz must be completed with grinding wheels, centering cups, indexing templates and bit holders. Product number begins with 8700-xxxx instead of 9500-xxxx (product code).

Grind Matic Manual B

Note!

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9213 Secor KAT_1_3.fm Page 86 Thursday, October 16, 2003 4:14 PM

secoroc grinding

Grinding

Grind Matic HG Grind Matic BQ2-DTH Grind Matic Manual B-DTH

134

Drilling in open pit mining

secoroc grinding

Grinding

Grind Matic X Grind Matic Senior Grind Matic Swing

Keep up to date with the world of mechanized rock excavation – Visit Mining & Construction on-line at www.min-con.com

Drilling in open pit mining

135

secoroc grinding

Grinding Diamond grinding wheels for button bits

Grinding wheels for steel grinding of button bits Diamond boron nitride

Full access to Atlas Copco products -everytime, everywhere.  136

Drilling in open pit mining

secoroc grinding

Grinding Diamond grinding cups for button bits

Grinding Ceramic grinding wheels for button, integral and insert bits Button bits

Integral bits

Insert bits

Grinding templates

r= 80 mm 3,5/32"

30

20

10

3 mm

1/8"

110° 40

0 5

10

10 9

D/3

15

1/4" 1/2" 3/4"

10

,9

5

D 8

12,7

Regrind when flat is 173 of button dia.

14

7

,5 Min. 0,5

Drilling in open pit mining

137

DRILL RIG OPTIONS

Silenced SmartRig Noise reduction

In many countries, strict noise restrictions are imposed for drilling in urban areas, and close to habitation or other sensitive buildings. This is exactly the situation for which the Silenced ROC D7C was introduced, as the first SmartRig for use especially in areas where noise levels have to be controlled. Silenced SmartRig ROC D9C has now been released to complete the product portfolio. Substantial efforts have been put into redesigning components and soundproofing enclosures, resulting in a 10dB(A) external noise reduction.

Feed enclosure

The most visible difference between the Silenced SmartRig and other computerized drillrigs is its patented feed enclosure, the frame and panels of which are formed from lightweight aluminium. There are four access doors, which are hydraulically operated from the cab. A rubber sliding skirt at its base encloses the drill hole, and this can be hydraulically raised for collaring. The whole enclosure is designed for quick demounting when not needed.

Lower fuel consumption

The advanced and more efficient hydraulic system on the Silenced SmartRig requires less power. Because its new engine delivers the right amount of power for each phase of the drilling operation in different rock conditions, fuel consumption can be reduced by up to 30%.

SmartRig automation

SmartRig has a PC-based control system that facilitates all kinds of automation in drillrigs. The hardware is designed to operate in every possible weather condition, and the software can be upgraded at site. SmartRig has built-in logging and monitoring functions, together with support for diagnostics and faultfinding. In the cab, the control system replaces hydraulic pipework and gauges with a display unit, considerably increasing the space and reducing the noise for the operator. In addition, the number of hydraulic components on the drillrig has been reduced substantially, and hydraulic efficiency is higher as a result. The need for electrical cables is also diminished.

Increased productivity

SmartRig facilitates increased shift capacity through faster positioning, to which can be added the productivity increase from automatic rod adding and auto feed alignment. Altogether, the Silenced SmartRig is a major step forward for the environment, presenting a flexible choice for quarries and civil engineering work sites.

138

Drilling in open pit mining

DRILL RIG OPTIONS

Angle and hole depth instrument

Angle instrument with sight

sate for the turning of the boom the same way as when the sight is turned.

The electronic angle indication system consisting of an angle sensor on the boom and feed, sight and graphic presentation on an LCD display. The sight makes it possible to drill parallel holes by selecting a reference point before the first hole is drilled. This reference point is then maintained throughout the entire round or as long as the direction of movement is the same. By turning the sight back to the same reference point the entire time regardless of how the drill rig travels, the instrument calculates how the feed inclination must be changed to maintain the same direction of movement. The angle sensor on the boom mounting allows the instrument to compen-

a

Display: Angle instrument with sight

Drilled depth instrument

In order to maintain control over the drilled depth, drill metres and penetration rate, the system is equipped with a drilled depth sensor.

The drill rig can be equipped with one of the following alternatives:

• Angle and depth measurement instruments with sight. • Angle, depth and laser plane instruments with sight.

e

Display: Drilled depth instrument

d a

b

f

f

e c

b

d

g

c

a Actual inclination front/back b Desired inclination front/back. c Actual inclination left/right d Desired inclination left/right e Reset f Graphic

Drilling in open pit mining

a Indication of selected measurement method b Reset of drilled depth counter c Accumulated drilled depth d Desired drilled depth when using automatic drill stop e Current drilled depth f Speed Penetration rate g Activation of the laser plane function

139

DRILL RIG OPTIONS

Water mist system An optional water injection system on the drill rig, combined with reduced flushing air, produces the so-called water mist system - which can be used for dust protection or hole stabilization. The system is especially useful when starting a hole or drilling through the first metres of soft rock or overburden. Also, in certain types of rock where dust suppression can be a problem for deep holes, water mist can be used as an alternative to the conventional dust collector. • The water mist system consists of a water tank, safety valve, strainer, two cocks, two valves and one check valve. • The water in the pressure tank is pressurized by the rig’s air system through a hose with an adjustable nozzle. The quantity of water can be finely adjusted using a valve on the water mist system. The system is cont- rolled by a switch located on the drill panel. • The system is depressurized by a blow-down valve when the compressor on the drill rig is deactivated. In order to meet customer demands, all rigs can be equipped with the water mist system - whether they are top hammer, DTH, pneumatic or hydraulic.

Equipped to operate the water-mist system: an Atlas Copco ROC F7 crawler rig, fitted with a pressurized water tank.

140

Drilling in open pit mining

DRILL RIG OPTIONS

Lubrication system The Quicklub lubrication system is designed to provide a relatively simple and inexpensive method of centralizing and automating the lubrication of machinery bearings. The system dispenses small measured amounts of lubricant at frequent intervals while the machine is operating. With a fully automated system, the lubricant is supplied by an electric pump through one or more distribution blocks to each point covered by the system. Even those hard to reach are assured of being properly lubricated and purged of contaminants. Up to 300 lubrication points can be served, depending on the length of the hose. • Reliably distributed lubricant in predetermined amounts. • Delivers lubricant to the connected lubrication points in a safe manner. • With three pump elements mounted, the pump can serve three separate lubrication circuits. • Each lubrication circuit is equipped with a safety valve that holds the pressure within permissible values. • If there is a block in a lubrication circuit, lubricant will leak from the safety valve. • Works through lubrication cycles (interval time, prop agation time and load time) • Pumps grease up to NGLI 2 at temperatures between -25 degrees C and +70 degrees C. • Can be used down to -40 degrees C if special low temp erature grease is used.

Quicklub lubrication pump.

Drilling in open pit mining

141

DRILL RIG OPTIONS

COP OIL

A new oil for Atlas Copco pneumatic and hydraulic rock drills, and DTH hammers that unites technology and environment.

Main features

The development of lubricating oil for pneumatic and hydraulic tools has been driven by the high demands on environment and reliability. COP OIL is made of carefully selected components that give the highest technical performance. COP OIL has a broad temperature range that gives you optimum operation in the most variable air temperatures. It withstands heavy loads and protects against wear and corrosion. More and more users are recognising the advantages of using environmentally adapted lubricants. In applications where lubricant is contaminating the surroundings, the use of environmentally adapted lubricants will therefore be a strong coming demand. COP OIL is based on renewable raw materials that are readily biodegradable. COP OIL is specially developed for Atlas Copco pneumatic and hydraulic rock drills and down-the-hole hammers.

Biodegradability according to OECD 301 COP OIL Mineral oil 100%

10 days Readily biodegradable

60%

28 days

142

COP OIL

• Excellent lubricating properties. • Reduces the risk of scoring and abrasion. • Protects against corrosion and oxidation. • Insensitive to air temperature variations. Works equally well throughout the temperature range - 35°C to + 45°C (-31oF to +113oF). • Adhesion and larger drop formation contribute to the very good lubricating properties. • Based on > 90% renewable raw materials. • Readily biodegradable according to OECD301

Additives in the oil are:

• Approved in accordance with the German authorities ”Blue Angel” • ”Approved” in accordance with the Swedish authorities ”Ren Smörja”

Technical data Density, 15°C: Viscosity at 40°C: Viscosity at 100°C: Index of viscosity: Flame point Lowest flow temperature:

COP OIL 927 kg/m³ 65 cSt 13.4 cSt 215 250ºC (482ºF) - 39ºC (-38ºF)

Part number 3115 3125 00 3115 3126 00 3115 3127 00

Can 10 litres Can pallet 48 x 10 litres Drum 208 litres

Using Atlas Copco COP OIL ensures that you are doing your best for both the environment and your equipment! Drilling in open pit mining

DRILL RIG OPTIONS

COP Grease

COP Grease can be ordered either in a tube for use in the field together with a grease gun, or in a can for use in the workshop.

To keep the rock drill in perfect shape, it is necessary to use the right quality of gear box grease. That´s why we recommend you to use COP Grease – a grease specially developed for Atlas Copco´s hydraulic rock drills. The grease is thoroughly tested to cope with all the trials that the gear box of the rock drill is exposed to, such as damp, vibrations and high temperatures. COP Grease handles temperatures ranging from 40°C to 150°C and short term up to 220°C. It has excellent mechanical stability, providing high resistance under vibrating conditions.The smooth consistency ensures minimal temperature elevation in the gear. It has excellent load carrying capacity, is very resistant towards water, and has good rust preventing properties. COP Grease contains additives to prevent wear and corrosion, and to ensure good Extreme Pressure (EP) ability. The additives also improve the oxidation stability, making the grease suitable for use under extended periods of time at high temperatures. By using COP Grease, you can lower the maintenance cost and increase the life length of your rock drill. You can order COP Grease either in a cartridge for use in the field together with a grease gun, or in a can for use in the workshop. Drilling in open pit mining

COP Grease Items Cartridge Can

Typical inspections

Characteristics Thickener NLGI Penetration Worked 60 times Dropping point Baseoil viscosity @ 40 °C Baseoil viscosity @ 100°C

Content 0,4 kg 18 kg

P/N 3115 3422 00 3115 3423 00

Methods - - ASTM D 217 ASTM D 566 ASTM D 445 ASTM D 445

Units - -

Lithiumcomplex 1.5

mm/10 ºC mm2/s mm2/s

  305 >260   475     50

Tests and approvals

Classified as L-XDDIB1.5 according to ISO 6743-9 Classified as K1.5N-40 according to DIN 51502 SKF Emcor WWO, distilled water SKF Lubricity R2F run test A SKF Lubricity R2F run test B (150°C)

Handling and Storage

Avoid skin contact. Wash thoroughly with soap and water, after skin contact. Dispose of used grease properly. Safety data sheet available for professional user on request.

143

DRILL RIG OPTIONS

Hole Navigation System The Atlas Copco satellite-based Hole Navigation System (HNS) for surface drillrigs employs Real Time Kinematic (RTK) GPS for positioning accuracy, to within 10 cm in most situations. With HNS, there is no need to mark out holes, and the accuracy is such that all holes can be parallel, or different holes in each round can be drilled in a predetermined direction, according to the blasting pattern. The result is a controllable product, with better fragmentation and fewer boulders. HNS focus is currently on road construction applications, but the system can be used in any type of surface drilling. Using information on his display, the operator can navigate the rig to the coverage position for the given hole, and the computer will provide the information to place and align the feed exactly over the collaring position. Where HNS is used in quarries and mines, the drillplan should be provided by an external tool, such as ROC Manager, and transferred to the rig computer system via a PC card. Using ROC Manager, the operator selects a hole in the drillplan, and information on his display guides him to the correct position to start drilling. The time saved by not having to aim visually to set angles, and by being able to drill more than one hole from a single set-up, results in better rig utilization.

ROC Manager ROC Manager is a stand-alone PC-based tool for making drill plans, measuring hole deviation, and logging, presenting and reporting drilling data graphically. This infor-mation can be presented individually or in combination with other parameters, and used both during drilling operations, and by transferring logged data from the rig. Advanced MWD analysis is also possible as an option. ROC Manager 2.0 supports the IREDES format for data exchange on performance, quality and MWD logs, and on drill plans. A number of graphical tools are available for presentation of data in ROC Manager. These are sometimes customized at site to ensure that local rock conditions such as discontinuities, faults, and boundaries are correctly displayed.

144

Drilling in open pit mining

DRILL RIG OPTIONS

Automatic Feed Positioning When drilling the bench, the operator has to be sure that, not only is he drilling in the right position, but he is also drilling at the right angle. It is very important that the drill rig feed is set to an exact pre-defined angle, especially for longer holes, where a small error can cause a large deviation at the bottom of the hole. For example, a 2-degree feed angle error produces a 3.6 cm deviation for every metre drilled, resulting in a 72 cm deviation at the bottom of the hole. The longer the hole, the bigger will be the impact on blasting of even a small deviation. The automatic feed positioning function avoids mistakes during setting of the feed angle, and cancels out operator error. The operator simply has to press a button in his cab, and hold it until the feed is set to the correct angle. Automatic feed positioning reduces set-up time and ensures parallel holes, resulting in better blasting and smoother bench bottoms.

Automatic Rod Adding Adding rods to the drill string used to be a timeconsuming process. First this process was mechanized by the introduction of carousels, clamps and SpeedRods, and now it has been automated. The automatic rod adding system, AutoRAS, enables the operator to drill a hole automatically to a given depth, allowing him to leave the cab to carry out other duties such as maintenance checks or grinding bits, while keeping the drill rig in sight. The drilling is supervised by the drill steel break detection system, which shuts down the drilling operation if a breakage is detected. In particular, this ensures that no damage is caused to the drill rig if a rod breaks above the surface of the hole. The result of using AutoRAS is better rig utilization, evidenced by a couple of extra holes/shift, and more efficient use of the operator’s time by multi-tasking.

Laser Plane Using the laser plane as a reference level, all holes are drilled to the same depth, reducing drilling, blasting and crushing costs by way of better fragmentation, and cancelling the need for secondary blasting. A flatter, more uniform bench surface results, making loading and transportation easier.

Drilling in open pit mining

145

DRILL RIG OPTIONS

DCT dust collectors

DCT dust collectors create a dust-free working environment, wich in turn contributs to lower maintenance costs, and increased service lives of drilling equipment.

Protect operators and drill sites from drilling dust

Drilling dust poses a serious health hazard, not only to operators, but also to worksites in general. Silicosis can be caused by stone dust containing quartz particles with a granular size less than 0.005 mm. In view of this health risk, many countries have introduced stringent standards and measures concerning dust separation in rock drilling. DCT dust collectors remove virtually 100% of all drilling dust, and, most important of all, separate the microscopic stone particles.

Reduce wear and lower maintenance costs

Uncontrolled drilling dust can clog motors and filters on adjacent machinery, promoting faster wear through abnormal friction and overheating. This can lead to more servicing and repairs, and a costly decline in production. DCT dust collectors create a dust-free working environment, which in turn contributes to lower maintenance costs, and increased service lives of drilling equipment.

Increase nett penetration rates

Field experience has shown that, using DCT dust collectors, nett penetration rates can improve by 5-10%. This is partly because the drill cuttings are removed from the drill hole, reducing recrushing, and improving bit performance. Also, because the operator is able to spend more time at the controls, he is able to maintain constant supervision of the drilling sequence. 146

Two-stage filtration to separate drill dust

Atlas Copco DCT dust collectors operate via a two-stage filtration process that removes virtually 100% of all drilling dust. A coarse separator isolates 90% of dust in the first stage, thus reducing the risk of overload of the filters. Then the remainder is separated in secondary filters to get rid of the highly injurious, microscopic stone dust of particle size less than 0.005 mm.

High reliability

DCT dust collectors have very few moving parts. The drive ejector has been positioned behind the filters, creating a partial vacuum in the entire system. As a result there is no dust leakage, even in the event of a suction hose becoming damaged. The drive ejector operates continuously in clean, filtered air, eliminating risk of erosion by drill dust. Steady, high airflow speed in the suction hose counteracts blockage of the suction hose. Compressed air to the ejector does not pass by way of the filters, reducing their load. Atlas Copco DCT dust collectors offer effective, reliable dust separation with operational simplicity, while improving the working environment and increasing productivity.

Drilling in open pit mining

SERVICE WORKSHOPS

Mobile Service and Hose Workshops

For easy and convenient service of drill rigs and hydraulic hoses When you invest in an Atlas Copco drill rig you receive a quality product. Quality gives reliability, availability and high productivity, which is essential to make profit. But the quality of any machine has to be maintained in order to give continuous high performance and good operating economy. And that can only be obtained through regular preventive maintenance and the use of Genuine Parts from Atlas Copco. A service workshop located on site or close by is the key solution to rapid maintenance and repair routines. This is why Atlas Copco have designed and equipped mobile workshops to serve different servicing requirements.

lockable pedestal; shelves; tool-board with tool hooks; 14 m-long hose roll-up for air pressure; 17 m-long, 230 V electric cable rollup; writing desk with lockable pedestal; powder fire extinguisher; first aid panel; ventilation system; and heating fan.

Mobile Workshop

The fully equipped version of the Mobile Workshop comes complete with standard tool kit, comprising all hand tools needed for carrying out service and repair work; 30 t hydraulic press, with mandrel set; 500 kg extensible hoist beam with manual tackle; and a smalIpart cleaning booth, with exhaust. The Mobile Workshop can then be completed with a number of well thoughtout options of special tools, instruments and machinery to optimize efficiency. Mobile Workshops are suitable for installation of drill bit grinding equipment, and the Secoroc Grind Matic Manual B air-powered, handheld portable grinding machine can be supplied.

Convenient service

The latest enhanced versions of the well regarded Atlas Copco Mobile Workshop and Mobile Hose Workshop contain all of the equipment needed for maintenance and increased availability of rockdrills and drill rigs. They are housed in 20 ft ISO standard steel containers, internally insulated and fitted with non-slip aluminium floor plating. Each workshop container is equipped with heating and has a complete electric and compressed air line system for immediate connection to external electrical and pneumatic power sources.

Mobile Hose Workshop

A new approach to hose maintenance is the Mobile Hose Workshop with the hose assembly centre, a complete hose mounting workbench, designed to fulfil all your needs for a safe and professional assembly of hydraulic hoses with up to four reinforcement layers. The centre is delivered with a hose reel, cutting machine, peeling machine, marking machine, hose cleaning equipment and hose press. The centre is delivered with all the necessary accessories.

Basic Mobile Workshop

The container can be delivered standard equip as a Basic Mobile Workshop without any tools or machinery for those who wish to equip the container themselves. In this version it has a workbench, 2.5 m-long with vice and

Each container has two main doors at the front that open completely, and on one side they have a window with steel shutter.

View inside fully equipped Mobile Workshop.

View inside fully equipped Mobile Hose Workshop

.

The containers have a base socket provided for forklift transportation. The external dimensions of the containers are 6.0 x 2.5 x 2.6 m, and they weigh around 3 t, depending on equipment. The mobile workshops can be delivered for 230V/50 Hz and 380V/50 Hz, or other voltages on request.

2600

General information

2500

6000

Visit www.facedrilling.com for more information Drilling in open pit mining

147

MARKET MATERIAL

Conversion factors This unit

Times

Equals

Length mm (millimetres)...................... x 0.001......................= m cm (centimetres)....................... x 0.01........................= m dm (decimetres)........................ x 0.1..........................= m km (kilometres)......................... x 1000......................= m in (inches).................................. x 25.4........................= mm ft (feet)....................................... x 0.305......................= m yd (yard).................................... x 0.914......................= m miles.......................................... x 1609.......................= m Power kW (kilowatts)............................ x 1000......................= W Horsepower............................... x 735.5......................= W Horsepower, U.K....................... x 745.7......................= W ft.lbf/sec..................................... x 1.36........................= W Btu/h........................................... x 0.29........................= W Volume 1 (litres)...................................... x 0.001......................= m3 ml (millilitres)............................ x 0.001......................= l dm3 (cubic decimetres)............. x 1.0..........................= l cm3 (cubic decimetres)............. x 1.0..........................= ml mm3 (cubic millimetres) .......... x 0.001......................= ml in3 (cubic inches)....................... x 16.39......................= ml ft3 (cubic feet)............................ x 28.316....................= l Imperial gallon.......................... x 4.546......................= l U.S. gallon................................. x 3.785......................= l Ounces (Imp. fluid oz).............. x 28.41......................= ml Ounces (U.S. fluid oz)............... x 29.57......................= ml Pints (U.S. liq.).......................... x 0.4732....................= l Quarts (U.S. liq.)....................... x 0.9463....................= l yd3 (cubic yards)....................... x 0.7646....................= m3 Force kN (kilonewton)......................... x 1000......................= N kp (kilopond)............................. x 9.81........................= N kgf (kilogramme force)............. x 9.81........................= N Ibf (pound force)....................... x 4.45........................= N

This unit

Times

Equals

Mass (weight) g (grammes). ............................. x 0.001.................... = kg t (tonnes, metric)....................... x 1000.................... = kg grains......................................... x 0.0648.................. = g oz (ounce).................................. x 28.35.................... = g ozt (troy ounce)......................... x 31.10.................... = g lb (pounds)................................ x 0.4536.................. = kg tons (long, US).......................... x 1016..................... = kg tons (U.K). . ................................. x 1016..................... = kg tons (short)................................ x 907....................... = kg Speed km/h (kilometre/hour)............... x 0.2777.................. = m/s m/s (metres/second)................. x 3.6........................ = km/h mph (miles/hour)...................... x 0.45...................... = m/s mph. . .......................................... x 1.61...................... = km/h ft/s (foot/second)....................... x 0.3048.................. = m/s ft/s (foot/second)....................... x 18.29.................... = m/min ft/s (foot/minute)....................... x 0.3048.................. = m/min Frequency blows/minute............................ x 0.017.................... = Hz kHz (kiloHertz)........................... x 1000.................... = Hz r/min (rev/minute). . ................... x 0.01667................ = r/s degrees/second. . ....................... x 0.1667.................. = r/min radians/second . ....................... x 0.1592.................. = r/s Pressure bar.............................................. x 100....................... = kPa bar.............................................. x 100 000............... = Pa 2 kp/cm ........................................ x 0.98...................... = bar atm (atmospheres)................... x 1.01...................... = bar 2 psi (pounds/in )......................... x 6.895.................... = kPa psi............................................... x 0.06895................ = bar

Torque kpm (kilopondmetres).............. x 9.81........................= Nm Ibf in (poundforce inch) ........... x 0.11........................= Nm Ibf ft (poundforce foot)............. x 1.36........................= Nm

Area mm2 (square mm)..................... x 0.000001............. = m2 cm2 (square cm)........................ x 0.0001................. = m2 in2 (square inches).................... x 645....................... = mm2 ft2 (square feet).......................... x 0.0929................. = m2 yd2 (square yards)..................... x 0.8361.................. = m2 Acres ......................................... x 4047..................... = m2 Square miles............................. x 2.590.................... = km2

Equals Divided This   by    unit

Equals Divided This   by    unit

148

Drilling in open pit mining

ROC CARE Value-for-money rig service with extended warranty

Scheduled service. Inspection protocols. Extended warranty. ProCom*. These are the four key ingredients of ROC CARE, the new value-for-money service package for Atlas Copco surface drill rigs. ROC CARE is tailor-made for the construction and quarry business. It protects all that is essential to your drilling operations. It guarantees regular inspections and service. It extends the warranty on major rig components in order to secure your productivity. ROC CARE means security and peace-of-mind. *ProCom is a global, satellite-based system that monitors rig status.

Committed to your superior productivity

Learn more at www.atlascopco.com/surface

Straight to success

T he new ROC L7 4 0 CR has all the qualitie s you ne ed for optimal sur fac e drilling, featuring a high roc k drill ef fe c t and a s trong f uel - ef f icient engine. T his mas ter rig will increase your produc tivit y by drilling large and s traight holes of supreme qualit y at great sp e ed.* T he rig features our patented COPROD ® sys tem that c ombine s the high pene tration rate s of Tophammer drilling with the s traightne s s and ac c urac y of D own -T he - Hole drilling. Add to this it s unb eat able abilit y to handle poor roc k c onditions, and the new ROC L7 4 0 CR will help you drill s traight to suc c es s . * Hole range 10 5 mm - 18 0 mm (4"- 7" )

Learn more at www.atlascopco.com/surface

Printed matter no. 9851 6549 01

Committed to your superior productivity