Rigger
Short Description
Rigger...
Description
BASIC RIGGING
• • • • • • • • • •
Introduction Roles and responsibilities Wire ropes Slings, belt slings, round slings, Bow Shackles Rigging Hitches & Slinging Methods Basic Knots Chain blocks Pull lifts Tirfors, eye bolts, plate clamps, turnbuckles, hooks, lifting beams • Lifting Appliances • Procedure for lifting operations
• • • • • • • • • •
Introduction Roles and responsibilities Wire ropes Slings, belt slings, round slings, Bow Shackles Rigging Hitches & Slinging Methods Basic Knots Chain blocks Pull lifts Tirfors, eye bolts, plate clamps, turnbuckles, hooks, lifting beams • Lifting Appliances • Procedure for lifting operations
A. Mission This course on Lifting Equipment, Rigging, and Slinging is designed to identify and detail the mandatory requirements for the safe utilization of all lifting equipment operating on the Project. The course will also provide a clear understanding of Lifting tackles, Rigging and Slinging practice, Safe Working Loads, Different types of Cranes and Crane Signals.
B. Problem Analysis
Everyday, Routine Crane Operations – • cause most of our accident due to lack of adequate planning.
C. Expectation • • • • •
To analyze all lifts Ground Preparations Using proper lifting tackles Interpretations of capacity charts Operators and signalmen must maintain continuous and undivided communication
D. Objectives Upon completion of the lesson, participants will be able to: • List the four major causes of crane accidents. • Describe the pre-planning that is required before putting a crane in use. • State the main precautions that apply to working with cranes. • Explain at least three ways to eliminate hazards that may lead to injury when using cranes or slings to handle materials.
Roles and Responsibilities (Cont.) Rigging Superintendent – Ensuring that the lifting equipment and gear selected to work, has been inspected, certified and is maintained according to procedure – Ensuring that only qualified and competent riggers/slingers/banks-men are assigned to any lifting operations
Roles and Responsibilities (Cont.) • Appointed Competent Person (Lifting Equipment) – Third Party • Appointed Competent Person (Lifting Gear) – Third Party – Responsible for ensuring that the testing, examination and certification of lifting Equipment / Gear is carried out in accordance with the Requirement
Roles and Responsibilities (Cont.) Line Supervisors – Ensuring the adequate supervision of personnel, carrying out, or involved in, lifting operations – Ensuring that work method statements, task risk assessments, Lifting Plan /Rigging Study have been carried out – Ensuring that areas around the lifts are suitably barricaded and warning signs posted – Ensuring that the Load weight, shape and radius of lift are suitable for selected lifting equipment and gear
Roles and Responsibilities (Cont.) Riggers and Slingers – Identifying any defects in lifting gear – Conforming the weight, center of gravity and characteristics of a load prior to lifting
Roles and Responsibilities (Cont.) •Banks-men – Preventing all unauthorized personnel from entering the restricted area around the lifting operation – Ensuring that taglines are attached and used on all loads
Wire Ropes
Single Layer Rope • One layer of outer strands (usually 6 or 8) laid helically over a centre core of fibre or steel • Illustration - rope with independent wire rope core (IWRC)
Wires in a Stranded Rope Outer wire
Inner wire
Centre wire
Core wires
Stranded Ropes Single layer
Two layers
Three layers
Rotates
Rotational Resistant
Low Rotation
Rotation-resistant rope (Illustration is 35LS - Low rotation rope)
Rope Dimensions
Actual (measured) diameter 22.2 mm
Nominal diameter (d) 22 mm
Measurement of Rope Diameter (New rope) • 2 measurements at right angles at two positions spaced approximately one metre apart. – (Measurements taken over strand crowns)
• Average of the four measurements is the rope diameter.
Sheave Groove Profile
Wrong
Wrong
A damaged or overstrained rope may break and cause serious injury to anyone in its path.
Slings
WIRE ROPE SLINGS Inspection • • • •
• • • • • • • •
Safe working load stamping. Identification mark. Correct colour code (if applicable). Broken wires (Randomly distributed wire breaks are not to exceed 5% in any length of 10 diameters. Localised breaks are not to exceed 3 in a close group or in any one strand within a length of 6 diameters). Ensure rope end of the looped parts does not terminate inside ferrule. Excessive wear (max 10% loss of nominal diameter) Kinks. Exposure of core. Flattening of rope (especially in the eye). Stretch by reduction in diameter or circumference. Corrosion. Heat damage, look for evidence of discoloration, loss of lubricant, pitting and the presence of weld blobs.
Soft Eye
Soft Eye
Action
Endless
If any of the above faults are present refer to a competent person for through examination.
Maintenance • • •
Keep ropes clean and free from grit. Lubricate at regular intervals. Slings should be suspended from storage rack if not in use. Grommet
Examine all wire ropes for damage before use. Faults which may render a rope unserviceable include; Broken and fraying strands
•Corrosion •Kinking. •Broken and fraying strands.
Corrosion
Kinking
Wire Rope Capacities
The stresses in the legs of the sling increases as the angle between them increases. Using the human body and two buckets filled with water it will not be difficult to demonstrate the effects of lifting a load at narrow and wide angles. The arms represent the sling and lift angle.
Caution — Slung Angles are Critical Slings should always be used as near vertical as possible. In general if L is greater than S then the slinging is OK
On two leg sling work always be aware of the changing SWL factor with the changing angles of the slings.
Chain Slings Only Grade 8 or better ALLOY Chain can be used for overhead lifting purposes! All chain is not rated the same! Chain must have a capacity tag attached to it. Chains will withstand more rough handling and abuse, but a chain with the same rated lifting capacity of wire rope will be much larger in diameter and heavier in weight. Chains must be inspected daily before use and as often as necessary during use to assure safety. It is the riggers responsibility to do the inspections!
Chain Slings
SPECIFIC REQUIREMENTS FOR THE WEBBING SLING (FLAT & ROUND) • • • • •
All webbing sling shall; Be stored away from direct sunlight to minimize the effect of UV deterioration. Be stored on a non-corrodible rack, away from any source of heat. Not be used in knotted or twisted condition. Never be repaired. A damaged webbing sling or sling with damaged cover shall be discarded and taken out of service.
BELT SLINGS Identification • • • • • • •
Safe working load marking. Identification mark. Colour inspection code (if used). Condition of stitching. Tears or abrasions Burning of outer surface. Excessive wear.
Belt Sling with Eyes
If any of the above faults are present refer to a competent person for through examination.
Maintenance • • •
Keep surface clean and free from grit. Re-apply colour code if necessary. Sling should be suspended in storage when not in use.
Endless Belt Sling
Flat Webbing and Round Synthetic Slings Types of synthetic slings and fittings
Flat Webbing and Round Synthetic Slings • INSPECTION • Synthetic slings must be inspected before each use. • They must also be inspected by a competent person at least once every 3 months. If a sling is subject to severe conditions the inspections should be more frequent.
• Send slings for a proof load test at least every 12 months.
Flat Webbing and Round Synthetic Slings •
LOOK FOR:
•
Any external wear such as abrasion or cuts and contusions.
•
Internal wear which is often indicated by a thickening of the sling or the presence of grit and dirt.
•
Damage to the protective coating of the sling.
•
Damage caused by high temperatures, sunlight or chemicals (indicated by discolouration).
Flat Webbing and Round Synthetic Slings • Damage to the label or stitching. • Damage to the eyes or any terminal attachments or end fittings. • Where the sling is covered by a sleeve, the sleeve must cover the sling for the full length from eye to eye.
Flat Webbing and Round Synthetic Slings •
DISCARD A SYNTHETIC SLING IF:
•
It is considered that it has lost more than 10% of its original breaking strength. (Send the sling to the manufacturer for regular testing.)
•
The label has been removed or destroyed.
•
There is any damage to the sleeve or protective coating.
•
A nylon sling comes into contact with acid.
•
A polyester sling comes into contact with alkaline substances.
Flat Webbing and Round Synthetic Slings •
A polypropylene sling comes into contact with an organic solvent such as, paint, coal tar or paint stripper
•
There are any visible cuts on the sling.
NB: A nylon sling will lose more than 10% of its strength when it is wet. After 6 months exposure to sunlight send a sling in for testing.
Flat Webbing and Round Synthetic Slings
(b) Some damage to load-bearing fibres
(c) Badly damage sleeve
Flat Webbing and Round Synthetic Slings
(d) Load-bearing fibres have been cut
(e) Cut load-bearing fibres
(f) Broken load-bearing yarn
Flat Webbing and Round Synthetic Slings
(g) The use of hooks that are too narrow has damaged the eye of the sling
(h) Burn damage to sleave and load-bearing yarn
(i) Surface wear evident by furry surface
ROUNDSLINGS Identification A further category of man-made fiber slings is the round sling. This is manufactured from an endless polyester yarn and covered with a protective polyester sleeve stitched as illustrated.
Maintenance • • • • • • • • •
Safe working load markings. Identity number. Colour inspection code. Broken load bearing internal yarn. Cuts and abrasions to external cover. Cuts in stitching. Discoloration (due to chemical attack). Burn marks on outer surface. Knots.
Typical Round sling colour coding (Basic Configuration)
WLL Tonnes Colour 1.0 2.0 3.0 4.0 5.0 6.0 8.0 10.0
Violet Green Yellow Grey Red Brown Blue Orange
Endless Round Sling
Action If any of the above faults are present refer to a competent person for thorough examination.
Maintenance • • •
Keep clean and free form grit. Re-apply colour code if necessary Sling should be suspended in storage when not in use.
Round Sling with eyes
while inspecting the sling;
•
Sling should be laid out in good light and examined over its entire length for:
1. 2. 3. 4. 5. 6.
Damage caused by sharp edges (cuts) Damage caused by abrasion (burning or scuffing) Impact damage. Contamination by chemicals. ID tag with SWL marked ID number and length. Certification.
• The project operates a system where by all ―Lifting Equipment‖ is color coded with a unique color, at monthly intervals, after inspection where applicable. • Red color is reserved especially for items scrapped or not to be used. We have to comply with the project color coding system every 3 months or depending upon the project requirement.
Thumb Rules
Bow Shackles
SHACKLES Three types of shackles are commonly used for rigging applications. They are the anchor (bow type), chain shackle (Dshackle) and wide-body type shackle.
Many more different type shackles are available in the marketplace which should not be considered for rigging use.
Three suppliers of shackles are well known in the construction industry with Crosby and Green Pin being the leaders and most widely utilized. Le Beon shackles can occasionally be found as well.
Screw Pin Anchor Shackle
Screw Pin Chain Shackle
Bolt Type Type Anchor Shackle
Bolt Type Type Chain Shackle
Wide Body Shackles Greatly improve wear-ability of wire rope slings and can be used to connect high strength Synthetic Round Slings or Wire Wire Rope Slings by improving the D/d ratio. The sling bearing area increases by a minimum of 58 % which increases sling strength by a minimum of 15 %. Pins are smaller than equally rated quenched and tempered shackle pins and for instance a 75 Tonne wide body shackle can be utilized where a 55 Tonne normal quenched and tempered shackle is intended to fit.
Normal Shackle Reduced Sling Bearing Area in Shackle Bow
Wide Body Shackle Increased Sling Bearing Area up to 58 %. Increases usable sling strength up to 15 %
A simple Formula is used to calculate the Factor of D/d 0.5
Factor = 1 -
D / d
This means if a 25 mm Diameter Sling is used over a 30 mm Pin the Equation will be:
0 .5
1-
30 / 25
= 1-
0 .5 1.2
= 1 – 0.416 = 0,584
Rigging Hitches & Slinging Methods
Sharp bends in a wire rope sling reduce its strength and cause crushing. Fit a wire rope sling so that the minimum radius around which it is bent is atleast 3 times the diameter of the rope. Packing may be inserted to increase the radius of the bend.
Slinging Hazards
Slinging Hazards
SOFT EYE Not to be hammered down
Not to be hammered down.
DOUBLE BASKET OR PAIR BASKET HITCHES
A calculated, design approved and certified maximum load, normally specified in Kilograms (kgs) or Tones, up to which, an item of ―Lifting Equipment‖ is safe to operate.
CENTER OF GRAVITY The center of gravity of an object is that point at which the object will balance. The entire weight may be considered as concentrated at this point. Any suspended object (load) will center itself directly under the hook.
STABLE
Hook is directly above Center of Gravity
UNSTABLE Load is not above Center of Gravity
Load will shift until Center of Gravity is below the Hook
UNSTABLE Load is not above Center of Gravity
Rules to Follow When Slinging and Handling a Load Raise
Move Lower slowly
Basic Knots
ROUND TURN AND TWO HALF HITCHES Used to secure a rope to a column or post. Easily tied and does not jam. Will stand heavy strain without slipping.
BOWLINE A favorite knot with riggers and one of the best known and widely used of all knots. It is easily constructed and used wherever a hitch is required that will not slip, jam or fail.
REEF KNOT Also known as the square knot. Used to join two rope or lines of the same size. Holds firmly and is easily united.
Chain Blocks, Pull lifts, Tirfors, eye bolts, plate clamps, turnbuckles, hooks, lifting beams
USING CHAIN BLOCKS Head Lifting
Load Chain
Safety catch
Hook
Operating Chain
Head fitting Hand wheel Pawl Lever
Attach the head fitting to a suitable anchorage taking into account the load to be lifted, lowered or pulled. Hook with Safety catch
Operating Lever
Step Line
HOISTING OR PULLING: 1. Turn the lever to the neutral position. 2. Turn the hand wheel to adjust the chain to the required length. 3. Attach the load to the bottom hook, using appropriate slings and / or shackles. 4. Turn the lever to the up position. 5. Turn the hand wheel to take up the slackness in the chain. 6. Operate the handle backwards and forwards to lift or pull the load.
• • •
•
To lower the load, turn the lever to the down position. Operate the handle backwards and forwards to lower the load. When the load is securely in position, operate the handle to slacken the chain. Turn the lever to the neutral position and turn the hand wheel to give sufficient length of chain to be able to release the slings and / ore shackles.
HAND OPERATED WINCH / TIRFOR Identification A hand operated, lever controlled friction drive mechanism for lifting, lowering and pulling a load.
Identification •
Safe working load stamping.
•
Identity number.
•
Colour inspection code (if used).
•
Check for free operation of operation, reversing and rope release lever.
•
Check that correct shear pins are fitted, and pin condition is satisfactory.
•
Inspect complete machine for cracks, indentations or distortion.
•
Wear in operation jaws
•
Corrosion.
•
Inspect wire rope and hooks.
•
Correct rope.
•
Damage to casing.
This is a multi purpose tool made to pull and pay-off wire rope. A special wire rope is fitted through the machine and cannot be removed whilst there is a load on the winch. When the operating handles are actuated by hand, the rope is either pulled or paid-out through the machine. These machines are available in a range of Sizes to suit different working conditions.
1.
Uncoil the special wire rope, used with the machine, in a straight line to prevent loops which might untwist the stands or form kinks under tension.
Notched position
2.
Push the release handle into the notched position to open the jaws inside the machine.
3.
Insert the tapered end of the wire ripe into the machine at the hole in position A
Release handle
A
4.
Push the rope through the machine until it emerges at exit B.
5.
Anchor the machine using the correct slings. Fit them to the hook attached to the machine.
6.
Pull the wire rope through the machine until the desired length is reached and the rope becomes tight on the load.
7.
Lift the release handle out of the notched position and allow it to return to the operating position under its spring pressure. The rope is now firmly held in jaws fitted inside the machine.
B Hoisting or Pulling Fit the operating handle on to the actuating lever and work the handle to and fro. This action pulls the rope through the machine and automatically locks it in position when the operating handle is released.
Actuating lever
Fit the operating handle to the lowering lever and work the handle to and fro.
Lowering lever
this action pulls the rope back through the machine and when the handle ceases to move automatically locks the rope in position.
1.
Fit the operating handle on to the lowering lever and work the handle to and fro until all the tension is taken off the rope.
2.
Remove the anchoring slings. Push the release handle to the notched position to open the jaws inside the machine
3.
Pull the rope back through the machine.
T h e j a w s i n t h e m a c h i n e a u t o m a t i c al l y l o c k t h e rope in position. It is therefore impossible to r e l ea s e t h e w i r e r o p e f o r m t h e w i n c h w h i l s t t h e r e is any strain (load) on it.
PLATE CLAMPS Identification There are various types of plate clamps in use, the following three being the most common:
Inspection •
Safe working load stamping.
•
Identity number.
•
Plate thickness marking
•
Colour inspection code (if used).
•
Free working of assembly.
•
Condition of ―teeth‖
•
Wear at all bearing points and on pins.
•
Cracks, nicks and gouges.
•
Inspect weld (if used).
•
Security of all pins.
•
Deformation.
•
Corrosion.
•
Condition of springs
Universal
Vertical
Action If any of the above faults are present refer to a competent person for thorough examination.
Maintenance •
Keep clean and free from grit.
•
Lubricate moving parts if necessary.
•
Re-apply colour code if necessary.
Horizontal
Plate clamps are available in two basis designs, i.e horizontal plate clamps (sued in pairs and usually suspended by a two leg sling from a lifting beam) for handling plates in the horizontal position. (These clamps can also lift from horizontal to vertical and vice versa, but should NOT be used to transport plates horizontally).
Selection
Horizontal Clamps
Universal (Vertical) Clamps
The first consideration when selecting the clamp is how the plate is to be transported and stacked, ie horizontal or vertically. The second consideration is the weight of the plate to be handled which will determine the SWL of the clamps. The third consideration is the plate thickness which will determine the correct model of clamp with the appropriate jaw opening.
Pre-use Examination Before using any plate clamps, the following checks should be made:
•The SWL is adequate for the load. •The colour coding (where applicable) is current and the clamp has a plant number / ID mark.
Lock the jaw in the closed position and ensure the jaws have a firm bite on the plate.
Always i) ii) iii) iv)
Check that the plate is clean and free from mill scale, dirt, Oil and grease. Double check that the jaws are locked. Use an adequate number of clamps to balance the load. Lift slowly to allow the jaws to obtain a good grip.
Never Attach clamps to the side of the plate
Never •
Fast lower onto the floor as this could cause the clamp to open and release the plate.
•
Lift horizontally with a vertical clamp.
•
Lift more than one plate at a time.
•
Use large capacity clamps to lift light loads.
When using horizontal plate clamps, do not exceed the sling angles indicated below and do not lift more than one plate at a time unless the clamps are suitable, i.e. sheet bundle clamps
Never •
Use endless slings with clamp pairs as this practice can drastically overload the clamps.
COMMON TURNBUCKLE Turnbuckles (Rigging Screws) can be obtained with various types and combinations of end fittings, the most popular being the ―Jaw and Eye‖ type.
Jaw & Eye combination
Jaw & Jaw combination
Eye
Jaw
Stub
Hook
(Has Reduced capacity) The first consideration when selecting turnbuckles
Hook & Hook combination
Selection
is the SWL which is determined by the thread diameter.
Hook & Eye combination
The second consideration is the adjustability (commonly known as ―Take -up‖) of the turnbuckle. The take-up often varies with different patterns.
When using a turnbuckle in an application where vibration is present, (most areas in an engineering environment), it is extremely important to lock the end fittings to the frame or body to prevent them from unscrewing and possible releasing the load. The most popular and preferred method is to wire the eye or jaw to the body (see fig. 1). As an alternative (for open body type only) a split pin through the end of the screwed shank is acceptable (see fig – 2). The split pin has to be removed to facilitate adjustment. Should lock nuts be used, care must be taken not to over tighten them as this can put undue stress on the threaded shank (see fig – 3)
Lock wire will hold
Preferred Fig - 1
Acceptable Fig - 2
Caution Required Fig- 3
WARNING When turnbuckles are to be left under load for any length of time, eg temporary hangers for pope work, etc they should be visually checked on a daily basis to ensure they are still secure.
PRE-USE EXAMINATION Prior to using a turnbuckle in a lifting situation, visually examine it and ensure that: i)
The SWL is adequate for the load.
ii)
The colour code is current and the turnbuckle has a plant number / I.D. mark.
iii)
The threads are free from wear, stretch and impact damage.
iv)
The eyes/hooks are not worn or stretched.
v)
The clevis pin and pin holes are free from distortion/wear.
vi)
The threads are suitable lubricated.
Check for cracks & bends
Safety Turnbuckles must always have the threaded shank protruding into the body to ensure
Check for thread damage & bent rods that the load is borne over the correct length of the threaded shank.
Particular care must be taken when using ―Closed Body‖ type screws. It may be necessary
CORRECT UNSAFEshanks, to dismantle to dismantle the turnbuckle, measure the length of the threaded reassemble and use measurement to ensure the above ―unsafe‖ case is avoided.
Always tighten eye bolts to the correct position, but do not over strain them. Fit a shackle so that the minimum strain is imposed when the lift is made unless an eye bolt with link is used. Ensure the collar is hard down on the material and the eye in the right direction for the lift.
WEIGHT OF SPREADER BEAM AND LIFTING BEAMS Weight of spreader beams can be calculated from weight tables of the steel section, from which they are made, or obtained from the manufacturer‘s specification.
LIFTING APPLIANCES
• CRANES (Tower, Mobile, Crawler.) • Identification • Hand signals • Safety Procedures • Inspection
Rough Terrain (RT)
All Terrain (AT)
Crawler Truck Crane (TC)
Crane Selection Weights, Dimensions and Lift Radii expected Type of Lifting to be done The Crane Position, where the Load is to be lifted from, Access, Erection and Dismantling restraints Site Conditions
Site Review and Crane Setup Character of the Ground and Soil Conditions. Access and Stability Working Area Presence and Location of any Underground Hazards
• •
• • •
•
Be familiar with the lifting capabilities of the crane. Check the lifting equipment being used is in good condition, certified for use, correctly color coded, and is of sufficient capacity to carry out the lift. Ensure taglines are attached to loads which are likely to swing. Be aware of any obstruction within the crane radius and working area. Check that the area around the load to be lifted is clear and that the load is attached to the floor, transportation cradle or adjacent equipment. Ensure that the escape route is identified.
Set up the crane as close as possible to the load , set the outriggers and block out securely ensuring that the crane is as level as possible. You can use a level or the main block to level the crane. Barricade the area making sure that no other personnel other than the rigging crew are within the barricade. Prepare the load for lifting making sure all equipment used is of sufficient size and Safe Working Load including crane radius and boom length Rig the load once everything has been checked float the load making sure it is balanced this assists the crane to check his brakes and stability When all the checks have been completed continue with the lift following all safety procedures only one person giving the signals, using tag lines to control the load if required. Once the load has been placed into its final position remove all the equipment and barricades.
WHEN WORKING WITH CRANES YOU MUST BARRICADE THE WORKING AREA
. Z A W E D
CONES
. .
Z A W E D
.
. Z A W E D
Crane Mats
Isolate Working Area
CRANE HOOKS Most cranes are fitted with ‗C‘ type hooks to prevent snagging on protrusions such as handrails, etc., and in certain cases also have safety catch to prevent the eye of the lifting sling being accidentally displaced in the figure. Large cranes however tend to be fitted with ramshorn type hooks which could have an effect on the sling design.
Soft Eye Soft Eye
‗C‘ Hook
Hard Eye
Ramshorn Hooks
Poor Ground Conditions are a Factor in Many Accidents
Never attempt to make a lift from soft or unstable ground
Poor Ground Conditions are a Factor in Many Accidents
Over 50% of all crane accidents are the result of mistakes made and rushed sloppy work done when the crane was being put together, readied and placed to make its lifts.
REMEMBER: Failure to follow just one safety precaution can cause that accident, to men or machine.
Failure to Level the Crane is a Common Accident Cause What can happen when you swing over the side!
Just a little side tilt when lifting a load over the rear can become dangerous when swung over the side.
Load radius increases when swung over the side.
LEVELING THE CRANE The line Should lie dead in the centre of the boom in all positions, end, side and corner.
WRONG
RIGHT Leveling With the Load Line
Check That Cranes are Level
Possible Capacity Loss Due to being out of Level Capacity Lost
Boom Length and Radius
When out of Level
1°
2°
3°
Short Boom, Minimum Radius
20 %
20 %
30 %
Short Boom, Maximum Radius
8%
15 %
20 %
Long Boom, Minimum Radius
30 %
41 %
50 %
Long Boom, Maximum radius
5%
10 %
15 %
Accurate Calculations are available from the specific, applicable Crane Manufacturers
Failure to Level the Crane is a Common Accident Cause The machine must be level
Remember — capacity chart ratings are based on ideal conditions: • Standing on firm, level surface • CALM wind • No side loads or outswing of load • Good visibility • Machine in A-1 condition and equipped as when leaving the factory. When such conditions cannot be attained, loads being handled must be reduced to compensate. DON‘T FORGET: If a tipping condition is suddenly sensed — start lowering the load and retract or elevate the boom to bring the load in. Never lower the boom and aggravate the condition.
Many Crane Accidents are Caused by Poor Blocking Under Floats
Many Crane Accidents are Caused by Poor Blocking Under Floats
USE SOLID BLOCKING UNDER ALL FLOATS THE CRANE’S BEARING PRESSURE MUST BE DISTRIBUTED TO THE GROUND BY USING
LARGE TIMBER BLOCKING WARNING: Only cranes with approved free on wheels ratings can be used without outriggers set.
Set Outriggers Correctly
Set Outriggers Correctly OUTRIGGERS: Capacities are based on all outriggers fully extended. Working with outriggers partially retracted will reduce capacities and machine stability considerably and may cause an accident. If it is absolutely necessary to operate a machine with outrigger beams partially retracted, reduce capacities to those shown on the chart for ―on rubber‖. Remember — the machine must be level. DON‘T OPERATE WITH ONLY REAR OUTRIGGERS EXTENDED. If you swing over the side, the machine may tip over, or the boom may be damaged from side loadings because the machine is not level.
Set Outriggers Correctly When working a machine with mechanical (non-hydraulic) outriggers, make sure the beams are pinned in place, otherwise they can ―creep in‖ while operating, causing an unstable condition and possibly tipping the machine over. WARNING Before travelling make sure mechanical outriggers are securely pinned in position otherwise they can come out on the road and cause serious damage.
Set Outriggers Correctly HYDRAULIC OUTRIGGERS: When setting hydraulic outriggers make sure that the outriggers are set evenly otherwise severe twisting of the crane‘s chassis frame will result.
Exceeding the Rated Capacity of any Crane is Dangerous Overloads can damage the machine and such damage causes failure and accidents.
It looks like about 10 tonnes.
Whoops!
Spreads out the load so the supporting surface can support it
Transmits the load without bending or breaking
WRONG
Setting Up and Parking Do not set up too close to trenches etc., as the machine vibration can cause the walls to collapse.
WRONG
WRONG
Know Conditions and Use Precautions
Ensure Handbook and Chart are with Crane
Required Clearance for Operations near High Voltage Power Lines To 50 KV
10 ft.
3.05 M
over 50 to 200 KV
15 ft.
4.60 M
Over 200 to 350 KV
115 ft.
4.60 M
Over 350 to 500 KV
25 ft.
7.62 M
Over 500 to 700 KV
35 ft.
10.67 M
Over 700 to 1000 KV
45 ft.
13.72 M
All overhead Lines and other apparatus should be treated as live unless officially declared “DEAD” and “SAFE”. If in doubt, seek advise
During Thunderstorms and Lightening STOP Work and retract/lower Boom
Mechanical Advantage
Wrong
Correct
MECHANICAL ADVANTAGE
Wedge Socket
Two Block Cutout
Know The Radius Of The Load Watch for boom drawdown as the crane takes the load. This increases the radius and can result in the load drifting away from the crane. THE RADIUS WILL INCREASE WHEN A LOAD IS LIFTED. MEASURE THE LOAD RADIUS BEFORE MAKING CAPACITY LIFTS.
Always Ensure that the Hook has got a Safety Catch
Never let the Boom touch a Structure
It Might Cause the Boom to Collapse Or Damage
Use Taglines
Always Stand Clear of Suspended Loads
Never Let Anyone Ride on a Suspended Load
The Users Responsibilities
Crane Operator Rigger
Protecting Rigging From Damage or Environment Rigging components are expensive to buy and to replace! Use them properly and store them properly! Keep wire rope slings lubricated and all rigging stored out of the weather. Treat the rigging as though your life depended on it! Because it does if it fails! Don‘t use makeshift rigging or attempt to repair any rigging components. Knots tied in rigging reduces the strength by 50% or more!
Lifting Operations Procedure (Cont.) Lifting operation planning:
Planning shall basically contain and consider the following steps:
Weight of the load
Method of lifting
Working radius
Communication system
Ground stability
Existing services (AG / UG)
Height restriction
Competent resources
Over head power line
Selection of equipment
Lifting Operations Procedure (Cont.)
• Ground stability
– When planning a lift, consideration must be given to the ground conditions.
• Outriggers – Sound timber packing or metal plates shall be positioned under each outrigger pad / Crawler to distribute the load. These should be a minimum of 3 times the area dimension of the outrigger pad.
Lifting Operations Procedure (Cont.) – Outriggers must be fully extended on both sides when performing a lifting operation. – Outrigger pads are not to be permanently attached to outriggers
• A sign warning of the danger of overhead power lines shall be mounted in each crane.
Lifting Operations Procedure (Cont.)
Lifting Equipment
– The lifting equipment operator shall not begin the machine movement, until the banks-man is within his range of vision, or in radio contact, and the signal is given and understood. – Where several individuals are involved, the crane operator shall obey the signal of the banks men ONLY. The only exception shall be in the case of an emergency, when the crane operator can receive the Emergency Stop Signal from anyone
Lifting Operations Procedure (Cont.) Restrictions to crane operations – The most common restriction to lifting operations is bad weather, specifically high wind. – However, No lifts will be permitted at wind speeds exceeding 30 Knots or 35 Miles per hour. – When working in close proximity to overhead electric lines or cables, the crane shall not be positioned closer to the plumb of the nearest line or cable than a distance equal to the length of the crane Jib fitted, plus 6 meters measured along the ground.
Lifting Operations Procedure (Cont.) Communication – An effective communication system shall be in place for all lifting operations. – The type of system will depend on the nature of the task i.e., radio communication may be necessary when visibility between the crane operator and the Banks-man is restricted.
Lifting Operations Procedure (Cont.)
Color Code System
– The Color Code System shall be developed and implemented for all Lifting Gear used within the Project such as for slings, shackles, rope wire, belts. – The color shall indicate to the user and the inspector, that an examination has been performed within the prescribed period.
– A new color shall be introduced on regular basis as per the Project Color Coding System and each color shall be current for a specified period – Information boards showing the current color coding shall be posted at prominent locations at each work site where it is anticipated lifting operations will take place.
Lifting Operations Procedure (Cont.) Lifting Operations Check List – A Risk assessment shall be conducted prior to any lift being performed. – The lifting operations check list acts as a reminder and guidelines to the personnel concerned, and basically consists of the items shown below and listed in the Lifting Operations Procedure.
CRANE OPERATION ANALYSIS
"our plan for a safe job"
Crane: Date: Time: Crane has been inspected/ safe condition:. YesNo Job Location: Job Description: The weight of the load is: The swing radius of the lift is: Net crane capacity at this radius is: Is operator qualified to operate this crane? Is operator’s certification card current? Critical lift permit required for this lift? Crane level/outriggers fully extended? Is the rigger qualified for this task? Is sling/hardware in safe condition? Sling sizing/hookup reviewed? Do sharp edges have s ofteners? Tag lines needed to help control load? Center of gravity of load located?
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes Yes
No
Yes
No
Yes
No
EMERGENCY INFORMATION What is the wind direction? Reviewed emergency alarms/phone numbers Escape route(s): Location of eyebath/shower station:
Our evacuation assembly point is: Operator Signature: Rigger Signature: Signalman Signature: Supervisor Signature:
No
Yes
RIGGING PLA N
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