M.E. Laws, Contracts and Ethics Presentation

M.E. Laws, Contracts and Ethics

Presented By:

Presented To:

Leo Paulo P. Del Rosario

Engr. Medrado Castroverde, PME

3.9 Fixed Ladders, Catwalks, Runways and Platforms: a.) All metal parts or fittings of ladders shall be made of structural steel. b.) Fixed ladders shall be installed i nstalled so that: 1.

2.

3.

The distance from the back from the front of the rungs to the nearest fixed object on the climbing side of the ladder is at least 760mm. The distance from the back of the rungs to the nearest fixed object is at least 160mm. Except in the case of ladders equipped with cages, baskets or equivalent devices, there should be a clearance of at least 380mm from the center line of  the ladder on either side across the front of the ladder.

c.) If fixed ladders are used to ascent height exceeding 9,000mm. 1.

2.

Landing platforms should be provided for each 9,000 mm or a fraction thereof. The sections of the ladder should be staggered.

d.) Catwalks, working platforms or open sided floors 2,000 mm or more above floor or ground level, except platforms used for loading and unloading of  height, and small platforms used for motors or  similar equipment which cannot afford standing space for persons, shall be guarded on all open sides by standard railing and toe boards.

e.) Catwalks used for filling of tanks, cars or for  oiling may have the railing on one side omitted, if necessary, subject to the hazard of  falling being reduced by the use of runways not less than 560 mm in width. f.) All runways or platforms constructed over  conveyors or machinery shall be guarded on all open sides by standard railings and toe boards.

3.10 Yards, Gated ,Roadways, Walkway  a.) Plant yards shall be properly drained and graded in order to facilitate safe access to buildings and safe handling of material and equipment. b.) Drain pools and catch basins shall be provided where necessary, and be properly covered or  enclosed. c.) Ditches, pits and other hazardous openings shall be provided with substantial covers, enclosed, or  surrounded by substantial guards.

d.) Walkways, roadways and tracks for plant railways should be carefully laid out in such a manner as to avoid dangerous grade crossings. e.) Where premises are surrounded by fences or walls, separate entrance and exit gates should be provided for pedestrians, vehicular and railroad traffic. f.) Gates for pedestrian traffic should be located at a safe distance from those for vehicular and railroad traffic and should be of sufficient width to permit passage of employees at rush hours. g.) Safe walkways should be constructed along the shortest lines between important points.

h.) Walkways should not be located under the eaves of  buildings where they may become slippery. i.) Where it is necessary for pedestrians to cross railroad tracks or vehicular roadways, bridges or  under pass should be provided, and the track or  roadway should be fenced so as to prevent direct crossing at such points.  j.) Walking along railway tracks by unauthorized persons should be prohibited. k.) Railings should be installed along walkways on bridges, on steep slopes, at slippery places and at places where pedestrians are liable o injury by passing vehicles.

l.) Roadways for automobiles, tractors or other  vehicles should be soundly constructed with surfaces made of good working materials. m.) Roadways should be of adequate width, and where used by two way traffic, shall be at least twice the width of the widest vehicle normally used, plus 1, 2500 mm. Sufficient clearance from overhead structure should be provided. n.) Where the establishment of grade or level crossings cannot be avoided, such crossings should be protected by watchman, gates or automatic signals. o.) Substantial railings or Walls should be provided along bridges, sloped and sharp curves.

Section 4.0: MACHINERY AND EQUIPMENT

4.1 General Requirements a.) All heavy machinery should be supported on solid foundations of sufficient mass and base area to prevent or minimize the transmission of  objectionable vibration to the building and occupied space and to maintain the supported machine at its proper elevation and alignment. b.) Foundation mass should be from 3 to 5 times the weight of the machinery it is supposed to support, or  may be designated in conformance with Section2.4.2.





If the unbalanced inertial forces produced by the machine can be calculated, a mass of weight equal to 10 to 20 times the forces should be used to dampen vibration. For stability, the total combined engine, driven equipment, and foundation center of gravity must be kept below the foundation top.

c.) The weight of the machine plus the weight of the foundation should be distributed over a sufficient soil area which is large enough to cause a bearing stress within the safe bearing capacity of the soil with a factor safety of five (5).

d.) Foundations should be isolated from floor slabs or  buildings footings at least 25mm around its perimeter to eliminate transmission of vibration. Fill openings with watertight mastic.  When installing machinery above grade level of a building, additional stiffness must be provided in the structural members of the building to dampen machine vibration. e.) Foundations are preferably built of concrete in the proportion of the one (1) Measure of Portland Cement to (2) Measures of sand and four  (4) Measures of screened crushed stones.  The machine should not be placed on the foundation until (7) days have elapsed or operated until another seven (7) days have passed.

f.) Concrete foundations should have steel bar  reinforcements placed both vertically and horizontally, to avoid thermal cracking. Weight of reinforcing steel should be from ½% to 1% of the weight of foundation. g.) Foundation bolts of specified size should be used and surrounded by a pipe sleeve with an inside diameter of at least three (3) times the diameter of the anchor bolt and a length of at least 18 ties the diameter of the bolt. No foundation bolts shall be less than 12 mm diameter.

h.) machine should be leveled by driving

wedges between the machine’s base and concrete foundation and with the aid of a spirit level. Grout all spaces under the machine bed with a thin mixture of one part cement and one part sand. The level wedges should be removed after grout has thoroughly set and fill wedges holes with grout.

4.2 Specific Requirements a.) For Stacks – Stacks and foundation become integral structures. The Maximum pressure on the soil is equal to the pressure due to the weight and the wind movement. Allowable pressure may be taken as the sum of  2,566.36 kg/m2/m deep foundation plus 2,566.36 kgm2/ due to wind or a total 5,132.73 kg/m2/m depth of foundation.

1.

2.

Guyed Steel Stack  – These are used principally because of  their relative cheapness. Heavy foundations are necessary. Guyed Stacks seldom exceed 1.83 m diameter and 30.48 m high. Guys are usually applied in one to three seats. The angle between the stack and guy wire is usually 60o , and the angle between wires in a set is 120o for a set of three. Reinforced Concrete Chimney  – Together with its base, this chimney forms an integral structure. Wall thickness decreases progressively to the top of the stack. Less area is required than for masonry or self  – supporting steel stack because of the relatively thin walls compared to masonry stacks and the elimination of the conical flare of the self-supporting steel stack. They can be erected rapidly. The success depends to a great extent upon the care with which material is selected, mixed and poured.

 Table 2.1  Approximate Weight of Guyed Stacks Per  Meter of Height Thickness of Material

Stack Diameter 

2.75

3.57

4.37

4.76

6.35

(mm)

mm

mm

mm

mm

mm

Weight of Stacks kg/m 750

61.29

75.39

-

-

-

840

67.35

82.70

-

-

-

915

73.46

90.29

111.00

-

-

990

79.27

97.45

119.95

136.19

-

1065

85.02

104.90

127.25

144.53

192.66

1220

97.15

119.50

144.83

165.54

223.50

1370

-

135.74

165.24

185.65

250.62

1525

-

150.49

182.82

208.45

273.86

1675

-

-

200.85

229.16

301.43

1830

-

-

218.58

249.13

327.35

b.) For Steam Turbines  –Foundations should have sufficient weight and mass to hold the turbine rigid against vibration. The maximum unit pressure of  turbine and generator on the reinforced concrete should not exceed 17.62 kg /cm 2 Concrete shall be 1-2-4 mixture, well placed and seasoned. It should be designed to support the machine load plus the machine load plus 25% for impact, condenser load, floor loads and dead loads. c.) Diesel Engines  – Manufacturers supply foundation drawings with each engine sent out. In the absence of such drawing, foundations may be designed but in event should absurdly shallow foundations be allowed. Foundations perform three functions:

1. 2.

3.

Support the weight of the engine. Maintain proper alignment with the driven machinery, and  Absorb the vibration produced by unbalanced forces created by reciprocating revolving masses. (a) Materials. The foundations should be concrete, of 1 part cement, 2 parts sand and 4 parts broken stone or gravel (50 mm max). The entire foundation should be poured at one time, with no interruption than are required for  spacing and ramming. The top should be level and left rough for grouting. After pouring, the top should be covered and wet down twice dialing until the forms are removed at the end if the third or fourth day. The engine should not be placed on the foundation until 10 days have elapsed, nor operated until after another 10 days.

(b) Soil Bearing Pressure  – The first objective is achieved by makings its supporting area sufficiently large. The safe loads vary from about 4,890 kg/m2 for alluvial soil or wet clay to 12,225 kg/m2 . (The latter is assumed to be safe load average.) in computation 2,406 kg/m2 may be used as weight of concrete. (c) Depth  – The foundation depth may be taken as good practical rule, to be 3.2 to 4.2 times the engine stroke; the lower factor for  well-balanced multi-cylinder engines with fewer cylinders, or on less firm soil.

(d) Weight  – The minimum weight required to absorb vibration could be expressed as a function of the reciprocating masses and the speed of the engine. However, for practical purposes it is simpler to use the empirical formula.  __  Wf  = e x We x √ N Where: Wf  = weight of the foundation in kgs We = weight of the engine in kgs e = an empirical coefficient N = engine speed , rpm

 Table 2.2  Values of “e” in Foundation Formulas

Type of Engine

Cylinder Arrangement

No. of  Cylinder/s

e

Single-acting

Vertical

1

0.15

Single-acting

Vertical

2

0.14

Single-acting

Vertical

3

0.12

Single-acting

Vertical

4,6,8

0.11

Single-acting

Horizontal

1

0.25

Single-acting

Horizontal duplex

2

0.24

Single-acting

Horizontal twin duplex

4

0.23

Double-acting

Horizontal

1,2

0.32

Double-acting

Horizontal with tandem

4

0.20

(e) Volume of Foundation - If the weight and speed of the engine are not known, the volume of concrete for the foundation may be estimated from the date in the following table:

 Table 2.3  Volume of Concrete Foundation, m3/kW 

No. of  Cylinders

1

2

3

4

5-8

High speed engine

0.152 0.095 0.076 0.065 0.057

Medium speed engine

0.190 0.118 0.095 0.080 0.072

Low speed engine

0.228 0.152 0.114 0.099 0.087

(f) Anchor Bolts – To prevent pulling out of the bolts when the nuts are tightened, the length embedded in concrete should be equal to at least thirty (30) times the bolt diameter. The Upper ends are surrounded by a 50 mm or  75 mm sheet metal pipe, 460 mm to 610 mm long to permit them to be bent slightly to fit the holes of the bedplate.

Section 5.0  Anti-Pollution for Industrial Building 

5.1 All machines/equipment which characteristically generate noise shall be provided with appropriate enclosures to control emissions so as not to cause ambient noise level higher than the quality standards set by the government agency concerned. If impractical, the buildings housing the same should be appropriately designed ors should be provided with means to achieve compliance with the standards. 5.2 Buildings intended for noisy manufacturing activities should be appropriately designed or should be provided with means so as not to cause ambient noise level higher than the standards set by the government agency concerned.