800 Cranes, Rigging and Lifting

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800 Cranes, Rigging, and Lifting

AbstractThis section will facilitate the practical design of rigging by Civil Engineers of allexperience levels and assist other Company personnel involved in the developmplanning, and execution of lifts. The section defines commonly used rigging termdescribes rigging components and equipment; establishes rigging procedure ansafety guidelines; outlines methods for finding loads in slings and designing padeyes; makes recommendations for test lifts and rigging component inspecti

The type of equipment that usually requires lifting in a refinery, chemical plant, producing location includes vertical columns, vertical and horizontal vessels, pumps, heat exchangers, compressors, electrical equipment, air coolers, smallwelded tanks, and other miscellaneous items. For requirements for lifting servicsee the Model Specification CIV-MS-4782, Lifting Services, included in Section 2000 of this manual. This engineering guideline and accompanying MoSpecification do not include requirements for offshore lifting.

Contents Page

810 Organizing a Lift 800-3

811 General Procedure for Evaluating and Performing a Lift

812 Data Required

813 Rigging Responsibilities

814 Lift Classification

820 Transportation and Lifting Methods 800-4

821 Transportation Method

822 Lifting Method

830 Safety Considerations 800-11

831 Good Rigging Practices

832 Working Around Power Lines and Near Electrical Equipment

833 Working in Confined Spaces

834 Voids And Holes

835 Crane Capacity Considerations

Chevron Corporation 800-1 April 1989

800 Cranes, Rigging, and Lifting Civil and Structural Manual

840 Inspection and Testing 800-14

841 Inspection

842 Testing

850 Rigging Diagrams, and Rigging Analysis and Design 800-16

851 Rigging Diagrams

852 Loads

853 Factors of Safety

854 Sling Forces

855 Wire Rope Stretch

856 Lifting Lugs (Padeyes)

860 General Rigging Information 800-31

861 Types Of Lifting Equipment

862 Miscellaneous Rigging Equipment

863 Wire Rope

864 Slings

865 Hitches For Wire Rope

870 Glossary 800-39

880 Model Specification 800-42

890 References 800-43

April 1989 800-2 Chevron Corporation

Civil and Structural Manual 800 Cranes, Rigging, and Lifting

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810 Organizing a Lift

811 General Procedure for Evaluating and Performing a LiftThe following steps need to be completed when performing a major or critical li

• Collect all the required data—Section 812• Determine safety considerations—Section 830• Choose lifting method—Section 822• Select transportation method—Section 821• Prepare rigging diagram—Section 851• Assemble lifting equipment• Verify crane capacity certificate• Inspect rigging equipment and components—Section 841• Proof test slings and shackles where required• Designate qualified signal man• Make trial run

812 Data RequiredAll rigging operations require a complete investigation in order to select the mebest suited for the lift. The items to be investigated depend on the complexity olift. The following list outlines the basic information required before selecting a method:

• Dimensions, weight, center of gravity, and configuration of the piece or piecto be lifted

• Inventory of available lifting equipment

• Method of attachment for handling. If attachment points or lifting lugs are provided on the piece, verify that they are intended for handling the entire piece and not a component.

• Restrictions by the equipment fabricator to prevent damage to the equipmeduring handling

• Sequence of proper assembly, when a piece consists of components

• Type, size, and number of slings

• Type of hitch

• Requirements for shipping skids or other handling devices and their availab

• Path of movement from the time equipment to be lifted is received to point final setting

• Lateral and overhead clearances in areas of restricted movement, particulafrom power lines



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• Crane operating radius

• Load restrictions on floors, structures, and access roads

• Proper orientation of piece in final position

• Change of load distribution that may occur during upending

• Holes, rocks, and soft ground in area of lift

• Need for mats, rollers, jacks, come-alongs, etc.

• Rating of spreader bars, shackles, slings, and load lines

813 Rigging ResponsibilitiesThe ultimate responsibility for all rigging lies with the design/construction enginor job engineer. Individual responsibility depends on whether rigging work is doby the Company or a contractor. Contractors are responsible for planning and executing the rigging operation, selecting the proper equipment and preparing rigging diagrams, all subject to review by the Company.

814 Lift ClassificationLifts can be classified as light, medium, heavy or critical. Suggested classificatioof lifts are:

820 Transportation and Lifting Methods

IntroductionThis section discusses choosing the type of transportation and lifting equipmen

821 Transportation MethodEquipment is generally moved on a truck. Selecting the proper hauling unit depon verifying the following:

• That the size and weight of the piece is within the dimensional and design cbilities of the truck

• That axle loadings do not exceed access road limitations

Light lifts Less than 10 tons

Medium Lifts Greater than 10 tons but less than 50 tons

Heavy Lifts Greater than 50 tons

Critical Lifts Lifts over operating equipment, lifts in hazardous locations, lifts in confined spaces, and lifts involving nonrigid objects like tank shells.



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• That clearances along access routes are adequate

• That the load will remain level and not tip

822 Lifting MethodThe lift can be made by mobile crane, gin poles, derricks, bridge crane, or hoistFigures 800-1 and 800-2 show lifting a vessel with two and with one crane resptively, and provide checklists of several items to be evaluated.

Mobile CraneTo choose a mobile crane for a lift, the following should be done:

• Prepare a layout study to determine the crane position that provides the mofavorable operating radius, boom length, boom clearance when stationary awhen swinging, and the required boom height.

• Check for underground obstructions which may be damaged.

• Check soil capacity.

Fig. 800-1 Typical Checks for Uprighting a Vessel with Two Cranes



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• Examine the erection site to ensure that outriggers and mats can be accomdated.

• Select a crane from the manufacturer’s chart which has the capability to hathe load. Figure 800-3, a manufacturer’s safe load chart for a hydraulic cranrelates a crane’s safe working load capability to the work radius and boom length. The following example demonstrates the process for verifying the cability of a crane for a lift. Note that this chart is only for one type of crane. Crane charts are different for each type of crane.

Example:

Verify that the contractor-proposed hydraulic crane “Pettibone Model 100-SC” (Figure 800-3) has the capability to lift and rotate 360° the piece of equipment described below.

Data.

1. Equipment

Size: 6 ft W x 14 ft L x 5 ft H

Weight: We = 23,500 lb

Center of Gravity: at centerlines.

Location (elevation) height: He = 50 ft above ground.

Fig. 800-2 Typical Checks for Uprighting a Small Vessel with One Crane



Fig. 800-3 Working Ranges and Safe Load Charts for Pettibone Multikrane Model 100-SC with 36-ft. to 84-ft. Boom (Courtesy Pettibone Corporation) (1 of 2)



Fig. 800-3 Working Ranges and Safe Load Charts for Pettibone Multikrane Model 100-SC with 36-ft. to 84-ft. Boom (Courtesy Pettibone Corporation) (2 of 2)



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2. Slings

Weight, WS = 100 lb

Crane hook height above ground at start of lift, hst = 18 ft.

Single point pick.

3. Crane

Hook block weight, Wb = 1000 lb.

Vertical length of block & lines, lb = 5 ft-6 in.

Distance centerline turntable to centerline boom pivot pin, lp = 4 ft-7 in.

Height of center of rotation of crane boom above ground, hcr = 9 ft-3 in.

Work radius, R= 35 ft

4. Load handling devices

Height of boom tip above center of rotation at end of lift,

Therefore, use crane working ranges chart with 36 ft - 84 ft boom height extended.

At the intersection of H = 73.5 ft and R = 35 ft read the boom angle, which approximately equal to 58° from the horizontal.

Weight, Wl = 200 lb

Total weight Wt = We + Ws + Wb + Wl

= 23,500 + 100 + 1000 + 200

= 24,800 lb

h = He + lb - hcr+ hst

= 50 + 5.5 - 9.25 + 18

= 64.25 ft

Boom length, L = [(R + lp)2 + h2)]1/2

= [(35 + 4.583)2 + (64.25)2]1/2

= 75.46 ft

H = h + hcr

= 64.25 + 9.25

= 73.5 ft



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Crane Capacity.

Use load chart with 36 ft - 84 ft boom

1. Crane on rubber and 360° rotation

Capacity = 2800 lb < 24,800 lb N.G.

Therefore, outriggers are needed.

2. Crane with outriggers and 360° rotation

With R = 35 ft and boom length = 76 ft

Capacity = 25,100 lb > 24,800 lb OK.

Conclusion: Proposed crane is marginal for the intended lift. A slight error in boangle, lift radius or load calculation would put this lift in jeopardy. Suggest look abigger crane or reducing lift radius for this crane.

Gin PolesThe primary gin pole features to consider when electing to use them as the liftinmethod are lift capacity and height of poles. Of equal importance are pole fountions and guy lines. For a more detailed discussion of gin poles see Section 86

DerricksSelect a derrick for a lift when large load capacity at long radius is needed. If somobility is required, be sure that there is space for a traveling gantry before choosing a derrick as part of a lift.

Bridge CranesBridge cranes should be considered when (a) the weight of the lift is within the crane capacity and (b) the lift will take place entirely within the crane’s area of coverage. In addition, ensure that vertical and horizontal clearances are sufficie

HoistsHoists are part of most lifting equipment. The most important factors to consideare:

• The hoist must have adequate capacity to spool the total length of rope required for the lift.

• When the angle at which the rope leaves or enters the drum produces a veor horizontal force on the hoist, anchorage must be provided to resist theseforces.



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830 Safety Considerations

IntroductionThis section discusses general safe rigging practices. It outlines precautions towhen working around power lines, in confined spaces, and in areas where holevoids are present. It lists inspection requirements for rigging components and ccapacity restrictions. Test lift requirements are also discussed. The Safety in Design Manual, Section 6, has more information on rigging safety.

831 Good Rigging PracticesThe following safe design practices apply to all types of rigging and are intendefor design engineers as well as field rigging personnel.

• Determine the weight of the load before designing the equipment to handleConsider whether vessels will contain fluid, sludge, etc, or whether equipmwill contain oil or cooling water. These items can and significantly to the nominal weight.

• If possible, distribute the load evenly on all legs of a sling.

• When using multiple leg slings, keep in mind that the load is not always divided equally. In a four-sling arrangement, two slings may carry the entireload.

• Design guy lines for gin poles with a minimum slope of one horizontal to onvertical unless the manufacturer specifies shallower slopes.

• Always specify the use of outriggers on truck and hydraulic cranes.

• Ascertain the load carrying capacity of the soil and, if necessary, use mats spread the load.

• Call for prooftesting of slings prior to their use. Wire rope should not be loadto more than 50% of its breaking strength, because the approximate elasticlimit of conventional rope is 55% of the breaking strength. Wire rope slings should be proof-tested to 40% of the breaking strength of the rope.

• The crane capacities listed in manufacturers’ load charts are based on the machine being level. The importance of leveling the crane cannot be overephasized.

• Never walk or stand under suspended loads.

• Stay out of the bight of a line and do not step over or stand near a line undestrain.

• When fastening chain hoists, rope falls, or snatch blocks to permanent strutures, make certain that the structure is strong enough to support the load.

• Do not touch a running wire rope. Do not let your hand or fingers get near blocks and sheaves.



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• Always use the shortest boom possible.

• Never replace the shackle pin with a bolt; only the proper fitted pin should bused.

• Always refer to the manufacturer’s specification chart for the safe working loads of shackles.

• For lifts with traveling cranes, measure the actual radius. Do not rely on boangle indicators.

• Always use a tag line even on small lifts. It is much easier to maintain controf the lift than to regain control when it is swinging or spinning. For large liftair tuggers or other mechanical tag lines should be considered.

832 Working Around Power Lines and Near Electrical EquipmentThe following practices shall be used when rigging near electrical equipment.

No rigging should be done over energized high voltage lines. High voltage lineslines rated 220V or greater. However, even 110V is dangerous and caution shobe used.

No part of the rigging operation, including the boom, cables, and the load, shallcome closer to high voltage lines than specified in Figure 800-4.

A safety watch monitoring these clearances should be located away from the lif

• In transit with no load and the boom lowered, the lifting equipment clearancshall be a minimum of 4 feet for voltages less than 50 kV, 10 feet for voltagover 50 kV, but less than 346 kV, and 16 feet for voltages up to and includin750 kV.

Fig. 800-4 Required Clearances from Overhead High-Voltage Lines

Nominal Voltage, kV (Phase to Phase)

Minimum Required Clearance(feet)

0 - 50 10

51 - 75 11

76 - 100 12

101 - 125 13

126 - 200 15

201 - 300 19

301 - 400 22

401 - 500 25

501 - 700 32

701 - 1,000 42



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• The only exception to the above minimum clearances is where the high-vollines have been de-energized and visibly grounded or where insulating barhave been erected to prevent physical contact with the lines.

• Place guy lines so as to be free of any possible contact with electrical wires

• Near transmitter towers, an electrical charge can be induced in the equipmbeing handled. Prior to work, provide an electrical ground to the upper rotastructure supporting the crane boom, and attach ground jumper cables to thequipment being handled.

833 Working in Confined SpacesWhen lifting in tight quarters, take the following special precautions to assure asafe lift:

• Conduct a detailed investigation to identify all possible interferences in the vicinity of the work including overhead, at grade or underground.

• Plot in detail the location of the crane and/or other equipment with respect the work, including location of outriggers.

• Establish limits of allowable motion for the boom in both the vertical and hozonal directions for each crane location in order not to damage existing facties.

• Devise and provide means to protect existing operating facilities. Mechanicprotect small protrusions on operating equipment, such as bleeder valves abrackets, which could be damaged during the lift.

• Consider shutting down and depressurizing operating equipment which coube jeopardized by the lift.

• Determine the feasibility of making a crane lift by establishing the operatingarea requirements, such as the radius, the required length of boom, and thto be lifted.

834 Voids And HolesVoids under pavements, holes, rocks, and soft ground can affect the safe operaof the crane. Sudden subsidence of the ground can induce impact forces in excof design impact loads. Outriggers must rest on level surfaces which will suppothe load placed on them. If outrigger floats are allowed to settle into the groundthey lose their effectiveness, thus making continued lift operations unsafe.

835 Crane Capacity ConsiderationsFor a safe lift, the following issues must be considered:

• Crane ratings are based on machine standing level on a firm uniformly supporting surface.



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• Crane rating charts apply up to a stated maximum wind speed. Avoid operawhen the wind speed exceeds the crane design wind velocity.

• The crane rated loads do not account for the weight of rigging accessories,blocks, hooks, slings, spreader bars, jibs, material handling equipment, andother elements of lifting tackle. Their combined weight must be subtracted from the load chart capacity when determining the maximum allowable loadbe lifted.

• The maximum safe working load of cranes is determined from static loads.The capacity charts do not take into account impact loads due to the dynammotions of the load or crane.

• There is no standard procedure for determining the rating of cranes travelinwith suspended loads. Crane rating charts for operation without outriggers should not be used to determine traveling crane rating unless the capacity so states. Check with the crane manufacturer before traveling with a load.

840 Inspection and Testing

841 InspectionPrior to use, all rigging components should be inspected by a qualified crane inspector to ensure that they do not constitute a hazard.

Cranes• Verify capacity certificate.

• Inspect crane for overall good condition.

• Boom: check for bent lacing, damaged chords, damaged joint connections,boom joint sheave bearings and for wear in rope grooves.

• Load line: check for broken wires and general condition.

• Load block: visually check condition of bearings, for wear in rope grooves, and the operating condition of safety latch. Before every critical lift, test for non-visible defects by magnetic particle or radiography.

• Crane hook: visually check for deformation. Before every critical lift, test fornon-visible defects by magnetic particle or radiography.

Do not use:

– Hooks with cracks– Hooks with throat openings more than 15% of normal– Hooks with more than 10° twist from plane of unbent hook

• Boom lines: check for broken wires, particularly at pendant fittings, and general condition.



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• Main clutches and brakes: check operation of air or hydraulic systems. Theshould be able to hold 110% of line pull with full drums.

• Swing lock and brakes: check operation and general condition. They shoulable to prevent load from swinging in normal operation.

• Review history of crane to find out if it has been used for major lifts since it was last certified. The crane may have been overstressed since certification

Shackles• Check load rating.

• Check general condition visually and test by magnetic particle for nonvisibldefects.

Lifting Lugs• Check load capacity.

• Check general condition visually and test by magnetic particle, radiographyultrasonic gage for nonvisible defects.

Wire Rope SlingsSafety of used wire rope slings depends on the remaining strength. The decisioreplace the sling should be made by experienced personnel only.

Visually inspect the rope for signs of deterioration to determine if further use of rope would be unsafe. Look for the following:

• Reduction of rope diameter below nominal diameter

• A number of broken outside wires and the degree of concentration of such broken wires

• Worn outside wires

• Corroded or broken wires at end connections

• Corroded, cracked, bent, worn, or improperly applied end connections.

• Severe kinking, crushing, cutting, or unstranding.

842 TestingFor light and medium, both critical and non-critical lifts, the following tests shoube performed before a lift:

• Lifting gear assembly (slings, shackles, spreader bars, load blocks, etc.) Tea minimum of two times the lifted load or design load.

When it is impractical to test the rigging assembly to twice the lifted load (i.heavy lifts), lifting personnel will have to rely on a careful inspection of the rigging components outlined in Section 841.



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• Used slings: Test to two times their normal rating.

• Position the crane with all the rigging gear attached and make a trial run toverify clearances and operating radii.

• Rotate the spreader bar to make sure that it clears the crane boom.

• Where possible, pick up the load and hold it low to test the crane’s ability tohold the load.

• Repaired or altered cranes. Load test to 110 percent of the rated load to confirm the adequacy of repairs or alterations.

• Hooks for which no manufacturer’s load recommendations are available: Teto twice the load.

850 Rigging Diagrams, and Rigging Analysis and Design

IntroductionThis section discusses how to prepare and evaluate rigging diagrams and lists information that a complete diagram should contain. It gives the loads and the factors of safety that should be used in the design of rigging components. Methare presented for finding forces in unequal length slings and in slings for off-cenlifts. Common types of lifting lugs are shown, and the steps to be followed in thedesign are outlined.

851 Rigging Diagrams

Preparation of Rigging DiagramsA rigging diagram is essential for the successful transportation, lifting, and placof equipment in final position. Before the rigging diagram is prepared, the rigginoperation is first analyzed and the rigging method selected (see Section 820). Snon-critical lifts up to 50 tons can be made without rigging diagrams provided thlift is below 70% of the crane’s capacity as determined from the manufacturer’ssafe load chart.

A complete rigging diagram must show the entire rigging process and should shthe following minimum information when it applies:

• Type and capacity of lifting equipment (crane, gin poles, etc.)

• Crane boom length, radius, and location of outriggers if required

• Weight, dimensions and center of gravity of piece to be lifted

• A plot of the path of travel including all vertical and horizontal clearances frosuch items as adjacent equipment, power lines, and other encumbrances ohazards



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• Location, size, and capacities of lifting lugs, slings, and other rigging accesries as well as the method of attachment

• Type of tow tractor, including size, capacity, turning radius, trailer attachmemechanism, etc. This information is particularly important in narrow, limitedwidth plant access roads and for lifts in confined areas.

• Description, size, capacity, and location of miscellaneous equipment such adollies, jacks, hand winches, rollers, etc.

• Location of mats under equipment if required

• Location and orientation of equipment before, during, and after the lift

• Location of underground lines (utility, electrical duct banks or cables, etc.) afoundations

• Position of survey equipment. For critical lifts, surveying is important to ensthat loads remain within vertical and horizontal limits and stable during the lifting operation.

• Maximum allowable wind velocity for the lift. Excessive winds can cause thload to drift and strike the boom, other equipment, or obstructions near by.

Evaluation of Rigging DiagramsA rigging diagram, particularly one prepared by a Contractor, must be evaluatedthoroughly to make certain that it incorporates all necessary information for a saand successful lift. The evaluation process must verify that calculations and sizof critical items such as cranes, slings, shackles, etc., are correct, that the propfactors of safety have been used, and that all clearance diagrams are accurate

The evaluation process should address the following:

• Rigging Equipment

Confirm that the type of rigging equipment selected has the capability to liftthe load. If a crane has been selected, verify that the selected crane has ththe-side and over-the-rear capacity to lift the piece, especially for critical liftor for lifts in operating plants. For two-crane lifts both cranes should be as close in capacity and drum speed as possible, except when one crane is usa trailing crane. For additional precautions and restrictions regarding the uscranes, see Section 811.

• Equipment and Roadway Clearance

Check the rigging diagram to ensure that the path of travel shows all overhobstructions, including pipelines, walkways, guy wires, power lines; all obstcles at grade, such as fire hydrants, drains, signs, etc.; and the location of uground lines.



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• Soil Loads

Recently excavated and backfilled areas or areas with weak soils have limibearing capacity. Examine the rigging diagram to verify that cranes, dolliesand trailers are adequately supported and that the diagram includes cribbinmats under the crane and outriggers where required.

• Wind Loads

The rigging diagram should also be checked for the maximum allowable wivelocity.

• Lifting Lugs

Lifting lugs are often necessary for lifts. The rigging diagram should show ttype and location of lifting lugs. Lifting lug calculations accompanying the rigging diagram should be checked thoroughly. See Section 856 for more details.

• Slings

Depending on the angle of the sling, the sling load may be larger than its portion of the lifted load. If the sling is used in a choked position, the sling capacity must be derated. Loads and ratings of slings are discussed in detaSection 852. The rigging diagram should specify the minimum safe workingload for the slings.

• Shackles, Hooks, and Spreader Bars

The rigging diagram should also be checked to assure that the size and caties of shackles, hooks, and spreader bars are adequate for the intended lif

852 LoadsRigging components should be designed for the following loads and forces whethey exist:

• Dead Load

Dead load includes the weight of the slings, blocks, shackles, clevises, hoospreader bars, and other special rigging devices which may be used. The weight of the crane hooks, jibs, and other crane accessories are also includ

• Live or Lifted Load

Live load is the load of the piece being lifted.

• Impact Load

Rapid acceleration or deceleration of the lifted load and the dead load induimpact forces which must be considered in the design of rigging componenThe effect of impact forces on the piece of equipment being lifted must alsoevaluated. Quick take-up on a hoist or crane with slack or fouling in the connecting slings or ropes produces large impact forces that may be severa



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times the lifted load. The amount of impact depends on the rate of lift from at-rest position. To avoid large impact forces, the slack must be taken up completely before lifting the load. For the design of lifting lugs or other attacments and for slings, the live and dead load should be increased by the following percentages:

• Wind Load

The maximum allowable wind velocity is based on the ability of the boom toresist lateral loads and on the stability of the lift. Crane manufacturers can supply data regarding the lateral load capacity of crane booms. In the abseof definitive information, however, no rigging should be done when the steawind velocity exceeds 25 mph.

853 Factors of SafetyA factor of safety is applied to all rigging gear to insure against failure from loadwhose magnitude cannot be calculated exactly or from indeterminate material perties.

The factor of safety (F.S.) is defined as follows:

From experience and common engineering practice, the following factors of safshould be used in the absence of larger values required by local regulations or equipment manufacturers.

• Wire Rope

The minimum factor of safety of individual wire rope used for general hoistipurposes should be 5. Where the rope is wound around drums or sheaves smaller than the recommended minimum D/d ratio, the minimum factor of safety should be 7.

• Manila Rope

The minimum factor of safety for new grade No. 1 rope should be 5. For usrope (in service more than 6 months) the minimum factor of safety should b10. Manila rope is recommended only for very small lifts.

• Slings

The minimum factor of safety for slings, including end connection or bendinefficiencies, should be 5. As an example, a wire rope sling with an end contion efficiency of 80% would require a wire rope with 25% greater working

Lifting lugs or other attachments 100%

Slings 25%

F.S. Breaking or Yield StrengthWorking Strength

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strength than a wire rope in a sling with an end connection 100% efficient (100/0.8-100=25).

• Shackles and Hooks

The minimum factor of safety should be 5. In the case of hooks, the hook mbe centered over the load to allow for full lifting capacity, otherwise the hoocapacity should be derated. The amount of derating should be calculated bexperienced personnel only.

854 Sling ForcesThe load in a sling depends not only on the total load but also on the geometry the lift, i.e., length and angle of sling. To properly size a sling, the following procdure should be followed:

• Determine the weight of the load

• Choose the desired hitch

• Calculate the force in the sling based on the geometrical arrangement of thslings

• Select a sling of suitable working strength

For a sling load analysis, the use of a correct free body diagram is very importaThe center of gravity of the lift is always located directly underneath the lifting hook. For rated capacity of slings refer to the Safety in Designs manual.

Unequal Sling LengthsOne of the most frequently encountered loading conditions is where unequal sllengths are used to suspend a load in a level position. The load analysis for twounequal length slings is simple and straightforward as Figure 800-5 shows.

Three and four unequal length slings are sometimes used in equipment riggingsling load analysis is more difficult and in the case of four slings, unless the slinlengths are precisely calculated with respect to the center of gravity of the load the pick point of the crane hook, two diagonally opposite slings may end up takall the load. Instead of oversizing the slings to carry one-half the lifted load, a bsolution would be to use a spreader beam which equalizes the load in each paislings and prevents diagonal tension. The load analysis of three or four unequal length slings should be carried out by experienced civil engineers only.

Off-Center LiftsMany times a load, such as a turbine rotor, has to be lifted “on an even keel.” Wtwo equal length slings are used and the load is lifted without regard to the posof the center of gravity, the load will tilt until the center of gravity is directly belowthe crane hook. See Figure 800-6. A load in a tilted position could be a hazard personnel and or equipment. In order to avoid tilted loads, the size and length oslings should be designed so that the load is lifted level.



Fig. 800-5 Example 1—Two Unequal Length Slings



Fig. 800-6 Example 2—Lifting with Two Equal Length Slings without Regard to Center of Gravity



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855 Wire Rope StretchWire rope, like all other elastic members, elongates under load. Total wire ropeelongation (rope stretch) is caused by two factors. The first factor is the way therope is constructed and starts to develop as soon as a load is applied. It is causthe adjustment of the wires and compression of the core and it is permanent. Wprecise rope length is required and adjustment for length is limited, the rope shbe prestretched. This is often the case in critical lifts. The second factor is elastelongation of the wire rope under load. Provided the load is kept below the elaslimit, the rope returns to its normal length when the load is removed. The elasticstretch can be calculated by using the following formula:

∆L = PL/AE

where:L = rope length, in

∆L = elastic elongation of rope, in

P = applied load, lb

E = modulus of elasticity, psi (See Figure 800-7)

A = metallic cross-sectional area of rope, in2

The cross-sectional area can be found in wire rope catalogs. Without a catalogcross-sectional area of most six-strand wire rope can be estimated as follows:

A = 0.4d2, in2 where d = nominal rope diameter, in.

As seen in Figure 800-7, the modulus of elasticity varies with different rope construction. The modulus of elasticity will increase during the service life of therope or with an increase of the applied load. The modulus of elasticity of prestretched wire rope is approximately 20,000,000 psi.

Fig. 800-7 Approximate Modulus of Elasticity of Nonprestretched Wire Rope

Wire Rope Construction Modulus of Elasticity (lb/in2)

6 x 7 with FC 12,000,000 to 13,000,000

6 x 7 with IWRC 14,000,000 to 15,000,000

6 x 19 Class with FC 11,000,000 to 12,000,000

6 x 19 Class with IWRC 13,000,000 to 14,000,000

6 x 37 Class with FC 10,000,000 to 11,000,000

6 x 37 Class with IWRC 12,000,000 to 13,000,000

8 x 19 Class with FC 8,000,000 to 9,000,000

6 x 25 Style BFS 12,000,000 to 13,000,000

6 x 30 Style GFS 12,000,000 to 13,000,000



eter

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d

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line

t-

Example.

Calculate the elastic stretch of 200 feet of prestretched 1 1/8 inch nominal diam6x19 IWRC wire rope loaded to 25,000 lb.

856 Lifting Lugs (Padeyes)

GeneralLifting lugs, sometimes called padeyes, are welded to the piece being lifted to ftate lifting and erection. Not all lifts, however, need lifting lugs. For example, smpumps and electrical equipment on skids can be lifted with hooks, or with chokebasket hitches.

Lifts that usually need lifting lugs include columns, vessels, heaters, air coolersstacks, production skid mounted units, etc. The location and orientation of the lifting lugs depends on the rigging method and type of equipment. Some considations when locating lifting lugs are:

• By placing the lugs closer to the center of gravity of columns, the tailing loamay be decreased.

• For thin wall vessels, the location and number of lifting lugs may be dictateby the stresses imposed on the vessel shell during the lifting operation.

• For lugs on the side of vertical vessels, such as trunnions, the path the slinmake during upending must be clear of nozzles, support clips, platforms, oother obstacles.

Types of Lifting LugsThe types of lifting lugs most often used for lifting vessels are trunnion lugs, earlugs, and flange lugs. All of these lifting lugs require a complete structural analyto ensure a sound design.

Trunnion lugs and ear lugs are attached to the vessel by welding, and must thefore be installed by the vessel fabricator because welds on vessel shells frequerequire stress relieving. Trunnion lugs and earlugs are recommended over flanglugs for new vessels.

A trunnion lug is shown in Figure 800-8. This lug is used on heavier vessels.

An ear lug is shown in Figure 800-9. This lug is usually installed at the tangent or transition point of a column or vessel. In contrast to trunnion lugs, ear lugs present fewer interference problems between slings and nozzles, clips, and plaforms.

∆L PL AE⁄=

25 000, 200 12××0.4 1.1252 20 000 000,,××( )

--------------------------------------------------------------------=

5.93 in.=



Fig. 800-8 Trunnion Lifting Lug



Fig. 800-9 Ear Lifting Lug



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For existing vessels or new vessels without trunnion or ear lugs, flange lugs canused on vertical vessels with top nozzles. Flange lugs should only be used 1) wa complete structural analysis shows that the nozzle is strong enough to take thlifting load, and 2) when tailing loads do not present any special problem. Figure 800-10 shows flange lugs with various weld attachments and lists severaitems to be evaluated.

Lifting Lug DesignDesigning or checking lifting lugs should be by experienced civil engineers in conjunction with experienced vessel designers.

To properly design a lifting lug, the weight and center of gravity of the piece mube known as well as the rigging arrangement, i.e., the number and geometry ofslings. If the actual weight of the piece is not known, the lug can be designed fothe working capacity of the attached sling. In a lift with three or four unequal lenslings in a single point pick, as mentioned above, two diagonally opposite slingsmay end up taking the entire load. In that case, the lug should be designed to cone-half the lift load with an impact factor, I=100%. This means that each lug isdesigned to lift the static weight of the entire piece.

The centroid of the piece should be computed exactly so that the hook can be located directly over it. If this is not done, then the lifting lugs will not be orienteexactly towards the center of gravity and it will be subjected to out-of-plane bending stresses.

The design of padeyes should follow a systematic ordered approach and shoulbased on the American Institute of Steel Construction (AISC), Manual of Steel Construction.

Following is a suggested step-by-step procedure for the design of padeyes.

1. Calculate sling load and determine sling orientation, if not given. Both the sling load and direction affect the stress distribution in the padeye.

2. List design data

– Governing code AISC– Sling load– Padeye material properties (yield strength Fy and tensile strength Fu).– Welding electrode type and nominal strength

3. Sketch the padeye and show its location relative to the piece being lifted.

4. List allowable stresses

– Tension: Ft = 0.45 Fy– Shear: Fv = 0.40 Fy– Bearing: Fp = 0. 9 Fy– Bending: Fb = 0. 6 Fy



Fig. 800-10 Flange Lifting Lug (1 of 2)



Fig. 800-10 Flange Lifting Lug (2 of 2)



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– Welds: allowable stresses in accordance with Table 1.5.3 of AISC “Specation for the Design, Fabrication and Erection of Structural Steel for Buildings,” 1978

– Combined stresses:fcr = [f 2

bx - (fbx)(fby) + f 2by + 3fv]1/2

where

fcr = critical stress ≤ Fy

fbx = bending stress about X - axis

fby = bending stress about Y - axis

fv = shear stress in xy - plane

5. Select shackle size based on sling load, using factor of safety of 5 and list controlling dimensions and tolerances.

– Shackle size and capacity– Pin diameter and outside of eye diameter– Inside length– Inside width at pin and at bow

6. Select padeye hole size to accommodate shackle pin diameter. The size ohole should be as follows:

7. Calculate the padeye plate thickness and cheek plate thickness if required desired to minimize padeye plate size, based on allowable stresses in stepabove.

8. Calculate weld size

– Cheek plate to main padeye plate– Padeye to vessel or other piece

9. Check adequacy of equipment to which padeye is attached to verify that it capable of supporting the load from the padeye within the allowable stresseThe vessel fabricator and/or the engineering design group should be consufirst.

10. Summarize padeye design parameters

11. Detail padeye

Shackle pin diameter Hole size

1 inch and less pin diameter + 1/8 inch

greater than 1 inch but less than 2 inch pin diameter + 3/16 inch

greater than 2 inch pin diameter + 1/4 inch



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860 General Rigging Information

IntroductionThis section lists types of lifting equipment and miscellaneous rigging equipmenIt discusses construction and strength of wire rope, slings, and the different kindhitches used in rigging.

861 Types Of Lifting EquipmentDifferent types of lifting equipment are available to fill any rigging need. A rigginoperation analysis will indicate what equipment is best suited for a particular job

Mobile CranesCranes are the most useful equipment in heavy rigging. The improvements whihave taken place in cranes in recent years have greatly increased their lifting capacity. Crane mobility makes for a minimum amount of time for move-in, setuand move-out, and their long boom allows access to restricted areas.

• Hydraulic cranes are readily available, can usually travel on most public streets and highways with few restrictions, and can be made ready for riggifast because the boom requires no assembly. The majority of hydraulic crahave maximum working capacities that range from 5 tons to 40 tons, thougsome models can exceed 125 tons. They are suitable for light lifts and medlifts at short radii.

• Truck-mounted cranes have maximum working capacities to 300 tons and have longer booms. Small truck cranes, like hydraulic cranes, can travel onpublic streets and highways with limited restrictions. Large capacity truck cranes on the other hand are much wider than small ones (up to 16.5 feet) require travel permits before they can move over public streets and highwaThey are suitable for medium and heavy lifts, but because the boom requireassembly, it takes longer to prepare them for rigging.

• Crawler-mounted cranes can have capacities exceeding 600 tons. The largecrawler dimensions distribute the load over a larger area, thus resulting in lower bearing pressures than truck cranes of equal capacity. Depending onthe crawler width can exceed 20 feet. As a result, travel over public streets highways is severely restricted and they are normally disassembled for tranCrawler cranes are suitable for heavy lifts.

Gin PolesGin poles are used primarily for lifting tall, heavy columns and vessels in remotlocations where large capacity cranes are not available or confined spaces limittheir use. Compared to cranes, gin poles have larger capacities (up to 1200 tonand lower relative cost. Gin poles are usually used in pairs. The poles are guyefrom the top and pinned at the base. The load is raised or lowered by ropes reethrough sheaves or blocks at the top of the poles. Unlike cranes, however, capa



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charts for gin poles are given for the pole as a compression member only. The in the guy wires must be calculated from the geometry of the lift.

A complete analysis should consider wind and temperature loads too. The bottof gin poles should rest on sound foundation and must be anchored securely toprevent kicking out under the load. The top of gin poles should be guided by at least four guy lines to maintain them in a stationary position and to prevent rotaThe guy lines can be ASTM A586 Zinc-Coated Steel Structural Strand or ASTMA603 Zinc-Coated Steel Structural Wire Rope.

DerricksDerricks have relatively large capacities at long radii. They can be mounted eithon fixed foundations only a few feet above the ground or on top of high specialigantries. They are not as flexible as mobile cranes because they cannot be moeasily. Some mobility can be provided by traveling gantries.

Bridge CranesBridge cranes are often used in lifting operations when the load is to be placedwithin a building or space already served by the crane.

HoistsHoists are used in heavy lifting as part of the rigging system and are generally nsubjected to severe use. Design of the tackle arrangement for specific lifts is geally done on a trial basis and it starts with selection of a hoist of adequate capaThe line pull of a hoist decreases as the amount of load line on the drum increaA check should be made to insure adequate line pull and rope capacity for the entire lift.

862 Miscellaneous Rigging EquipmentA rigging operation often requires the use of miscellaneous rigging equipment. Some of the most common is listed below:

Chain HoistsChain hoists or come-alongs, as they are often referred to, provide a portable tofor applying tension. There are two types of chain hoists available: roller chain aconventional link chain. Conventional link chain is preferred in general rigging because it is less susceptible to wear than roller chain. Chain hoists range in sifrom a few pounds to 10 tons.

TurnbucklesTurnbuckles are positive tension fittings with limited capability for adjustment. They can be furnished with end connection combinations of eye, hook or jaw. Tworking load capacity ranges from 500 pounds to 75,000 pounds.



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JacksJacks, both hydraulic and mechanical, are useful in raising and supporting loadWhen raising a load with jacks, it is very important that the base of the jack be solid surface. If the piece to be raised is of appreciable height, consideration shbe given to using hydraulic jacks designed for use with a power pump.

Hydraulic jacks may be used to determine the weight of a piece. The total weigbeing supported can be computed with the aid of a calibrated pressure gage if effective ram area of each jack and the unit pressure on each jack are known. Jcapacities range from a few pounds to 500 tons.

RollersRollers are used to move loads horizontally. There are three general types of rowood rollers, steel pipe rollers, and manufactured flat top roller assemblies. Moa load on wood or pipe rollers requires a runway consisting of heavy timbers orbeams capped with wood planks or steel plate. The runway should be of sufficiarea to distribute the load, and an adequate number of rollers should be used tsupport the load without damaging the load or the rollers.

Manufactured roller assemblies require a smooth concrete or steel surface on wto operate. They range in capacity from 2 tons to 200 tons.

MatsMats provide a means for increasing the bearing area under cranes and outriggwhen soil bearing capacity is limited. The ground surface on which mats are plamust be graded to provide uniform level bearing. Mats are usually made of 6-toinch thick timber. They are sometimes made of steel members when greater rigis needed.

Shackles And HooksShackles are the most frequently used fitting for joining slings to rigging attach-ments or lifting lugs. The safe working load for shackles of the same size variesit depends on shackle type and manufacturer.

Therefore, shackles must be specified by safe working load, size, pin size, andmanufacturer’s model number. Hooks are also used as sling fittings for moderamaterial lifts and where the loads are connected and disconnected often. Only hooks with safety latches should be used.

863 Wire Rope

GeneralWire rope is widely used in slings, hoists, boom lines, etc. Wire rope is formed blaying strands of wire around a rope core. Each strand is made up by a numbersmall wires laid helically around a center wire in one or more layers. The rotatioof the wires and the rotation of the strands in a wire rope is referred to as rope Rotation is either to the right (clockwise) or to the left (counterclockwise). The



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ire of

center of the wire rope is called the core and may be made of fiber (FC), wire, plastic, or other material. Wire cores are of two general types: independent wirerope core (IWRC) or wire strand core (WSC). Wire rope with IWRC or WSC haslightly greater capacity (approximately 6%) than rope with FC, and has greateresistance to crushing under heavy bearing pressure.

Wire rope is usually designated by first the number of strands and then the numof wires in each strand. Therefore, a 6x19 wire rope would normally have six strands and each strand would contain 19 wires. However, depending on the wrope classification, the number of wires per strand can vary. For example a 6x1wire rope can have 16 to 26 wires per strand. The nominal diameter of the wirerope is the greatest diameter that can be measured.

Wire Rope StrengthRopes are classified into various grades according to strength and ability to withstand abrasion. In ascending strength order they are:

1. Mild Plow Steel.

2. Plow Steel (P.S.)

3. Improved Plow Steel (I.P.S.)

4. Extra Improved Plow Steel (E.I.P.S.)

5. Double Extra Improved Plow Steel (X.E.I.P.S.)

Manufacturers of wire rope publish breaking strength and sometimes safe workstrength values. The safe working strength is typically listed as 20 percent of thbreaking strength: i.e., factor of safety = 5. The manner in which wire rope is usaffects its strength properties. Ropes running over sheaves or drums are subjecbending stresses. The ratio of sheave diameter D to rope diameter d influencesefficiency.

Figure 800-11 shows an empirically derived curve that relates the efficiency of wrope to the diameter of the pin or sheave. As can be seen, the smaller the ratiosheave diameter to nominal rope diameter the smaller the efficiency.

The minimum recommended sheave diameter is 18 times wire rope diameter.



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864 Slings

GeneralSlings are made with wire rope, steel chain, natural fiber rope, and synthetic fibrope.

Selecting the proper size sling, length, and hitching arrangement will achieve thdesired orientation of the suspended load, will result in a stable lift, and will provide the required factor of safety.

Wire Rope SlingsWire rope slings are the most frequently used slings in general rigging. Wire ropslings are made by attaching fittings to the ends of premeasured wire rope lengSling capacity is affected not only by the strength of wire rope but also by the tyof end connection.

An end connection that distorts the wire rope least is the most efficient. The vartypes of end connections and corresponding approximate efficiencies can be foin “Safety in Designs” manual.

The appropriate end connection efficiency must be applied to the working rope strength to arrive at the working strength of the wire rope sling. If the sheave diaeter D to rope diameter d (D/d) ratio results in bending rope efficiency which isless than the end connection efficiency, then bending efficiency should be appliinstead of the end connection efficiency.

Fig. 800-11 Efficiency of Wire Rope when Bent Over Sheaves or Pins of Various Sizes



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Synthetic Webbing SlingsSynthetic webbing slings are made of nylon, polyester, and polypropylene. Becof their relative softness and width, synthetic slings have less tendency to mar oscratch machined, polished, and painted surfaces, or to crush fragile objects. Tare non-sparking and can be used safely in explosive atmospheres. Obtain maturer’s data on safe working loads, factors of safety, and allowable wear before using.

Steel Chain SlingsChain slings are used where flexibility, ruggedness, and resistance to abrasion high temperatures are important. However, chain failure is sudden, and unless circumstances dictate otherwise, the use of chain slings should be discouragedgeneral rigging. Check chain type, grade, and working load limit before using.

Natural Fiber Rope SlingsNumber 1 manila rope is the only fiber rope approved for hoisting. Normally, manila rope is used for lifting men. Load capacity of manila rope slings is showANSI B30.9, “Slings.” Manila rope is not recommended for general use as liftingslings. Use for very small lifts only.

865 Hitches For Wire RopeThe most commonly used hitches for wire rope are vertical hitch, choker hitch, basket hitch.

Vertical HitchThis hitch is also called a direct connection hitch. When used singly, it does notafford the best load control nor protection against spin. It is effective when usedmultiples with spreader bars or when two or more attachment points are providon the load. See Figure 800-13.

Choker HitchA choker hitch is made by simply threading one eye of the sling through the othand choking the load. A single choker hitch does not provide full contact with thload and should not be used to lift loose bundles or long loads. The double chohitch is made by doubling the sling and threading the double end through both

Double wrap choker hitches compress the load and prevent it from slipping outthe sling. See Figure 800-12.

Bending of wire rope at a choker hitch decreases the working strength of the robecause of bending efficiency. In a choker hitch, when the load is freely suspenthe center of gravity is directly under the point of choke.

The observed angle in this position is approximately 135°. Smaller angles occur when a choker hitch is used to turn a load or when the point of choke is not direover the centerline of the piece. Figure 800-14 shows the various choker hitch angles and relates the angle of choke to wire rope efficiency.



one ch

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to al-

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Basket HitchWith a single basket hitch, two parts of the cable support the load although onlycable is used. As a load is lifted with a basket hitch, the load is equalized on ealeg and therefore each leg supports half the weight. The basket hitch is easy toattach and is a good hitch when used under the right conditions.

The double wrap hitch is one of the best hitches for smooth cylindrical loads suas pipes and tubes. It is the safest hitch to use. The load is held in a loop with tcable exerting equal pressure for 360°. See Figure 800-15.

Reverse Basket Hitch and Single Length Double Basket HitchIn these hitches the bight of the sling bears on the crane hook. The sling is freemove over the hook so that the load in each leg of the sling is automatically equized.

These hitches can be used to lift loads with lifting lugs or trunnions located abothe center of gravity of the load. They can also be used to equalize loads in a plegs of a four-leg sling arrangement by using two equal slings and one long slinwith its bight over the hook.

Fig. 800-12 Choker Hitch Fig. 800-13 Single Vertical Hitch



Fig. 800-14 Choker Hitch Efficiency

Fig. 800-15 Basket Hitch



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870 GlossaryThe following terms are commonly used in rigging.

Area, Metallic. Sum of the cross-sectional areas of individual wires in a wire ropor strand.

Basket Hitch. Sling configuration that equalizes the load in both legs of a sling formed with a single wire rope.

Bight. A loop or slack part in a rope.

Boom. A metal beam or strut, pivoted or hinged at its lower end and with its uppend supported by chains, ropes, or rods reeved through sheaves or a block, ussupport or guide a load to be lifted or swung.

Boom Angle. The vertical angle from a horizontal line through the center of rotation of the boom and centerline of the boom.

Boom Length. The straight line distance of a boom from the lower end hinge to upper end load point or hoist sheave pin.

Boom Line. A wire rope for supporting or operating the boom on derricks, cranedrag lines, shovels, etc.

Bright Rope. Wire rope made of wires that are not coated with zinc or tin.

Cable. A term loosely applied to wire ropes, wire strands, manila ropes, and eletrical conductors.

Cable-Laid Wire Rope. A type of wire rope consisting of several wire ropes laid into a single wire rope.

Cheek Plates. Doubler plates attached to the sides of and centered around the padeye hole.

Chocking. Wedges used to keep round vessels from rolling. Usually of timber construction.

Choker. Sling hitched to form a slip noose around the object to be moved or lifte

Core. The center of a wire rope about which the strands are laid. It may be fiberwire strand, or an independent wire rope.

Counterweight. Weight used to supplement the weight of the machine in providistability for lifting working loads and usually attached to rear of revolving super-structure. Also called ballast.

Deflection. (a) Sag of rope in a span; usually measured at mid-span as the deptfrom the chord joining the tops of the two supports (b) Any deviation from a straight line.

Drum (Rope). A rotating cylinder with side flanges on which rope used in machioperations is wrapped.



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cks at

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le ne.

e

Eye or Eye Splice. A loop, with or without a thimble, formed in the end of a wire rope.

Factor of Safety (FS). Factor of safety is defined as the ratio between breaking oyield strength and working strength.

Fiber Core (FC). Fiber center of a wire rope.

Fitting. Any accessory used as an attachment for wire rope.

Gantry. A structure for mounting a crane or derrick. It can be stationary or adapfor truck travel by towing or by independent truck power.

Gantry (A-Frame). A structural frame, extending above the superstructure, to which the boom support ropes are reeved.

Gin Pole. Compression member guyed from top and pinned or in a socket at itsbase. The load is raised and lowered by ropes reeved through sheaves and blothe top of the pole. Usually used in pairs.

Grades, Rope. Classification of wire rope by its breaking strength. In order of increasing breaking strength: Mild Plow Steel, Plow Steel, Improved Plow SteeExtra Improved Plow Steel, Double Extra Improved Plow Steel.

Guy (Line). A rope used to steady or secure the mast or other member in the desired position.

Guy Derrick. A fixed derrick consisting of a mast supported in a vertical positionby guys capable of being rotated, and a boom whose bottom end is hinged or pivoted to move in a vertical plane with a reeved rope between the head of the and boom point for raising and lowering the load.

Hitch. The manner of using the sling to support a load.

Hoist Line. See load line. In lifting crane service, refers to the main hoist. The secondary hoist is referred to as the whip line.

Hook Block. Block with hook attached used in lifting service. It may have a singsheave for double or triple line, or multiple sheaves for four or more parts of a li

Independent Wire Rope Core (IWRC). Wire rope used as the core of a larger rope.

Jib. An extension attached to the boom head to provide added boom length for handling specified loads. The jib may be in line with the boom or may be offset.

Lang Lay Rope. Wire rope in which the wires in the strands and the strands in thrope are laid in the same direction.

Lay. Manner in which wires are helically laid into strands or strands into rope.

Lifting Lug. Attachment on equipment to be lifted.

Load Block, Lower. The assembly of sheaves, pins, hook or shackle and frame suspended from the hoisting ropes.



f

ports

oved.

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d hed manu-

nd nt or

her

ss n

Load Block, Upper. The assembly of sheaves, pins, shackle, swivel, and frame suspended from the boom by solid links or direct connection.

Load Line. Another term for hoist line. See also whip line.

Mats. Supports or floats used for supporting machine on soft ground. Usually otimber construction.

Outriggers. Extendable arms attached to the mounting base, which rest on supat the outer ends to increase stability.

Pressed Fitting. Fittings in which wire rope is attached by pressing the shank enclosing the rope. See swaged fittings.

Prestressing or Prestretching. Stressing a wire rope or strand before use under such a tension and for such a time that the constructional stretch is largely rem

Radius of Load. The horizontal distance from the axis of rotation to the centerlinof boom point sheave.

Rated Load (or Crane). Rated loads at specified radii are the lesser of a specifiepercentage of tipping loads or the machine’s structural competence as establisby the manufacturer, and are the maximum loads at those radii covered by the facturer’s warranty.

Reeving. A rope system in which the rope travels around drums and sheaves.

Rigging. A combination of slings, shackles, hooks, load blocks, spreader bars, aother attachments that are used to support, lift, manipulate, and place equipmeother loads in their final position.

Safety Factor. See Factor of Safety (FS).

Safe Working Load (SWL). Proper load which the rope, shackle, etc., may carryas determined by manufacturer’s data, tests, and applicable codes.

Safety Hook. A hook with a latch to prevent slings or load from accidentally slip-ping off the hook.

Shackle. A U-shaped fitting with a pin.

Sheave. A grooved pulley for use with rope.

Side Loading. A load applied at an angle to the vertical plane of the boom.

Sling. The rope assembly which connects the load to be lifted to the crane or otlifting device.

Slings, Braided. A very flexible sling composed of several individual wire ropes braided into a single sling.

Splicing. Interweaving of two ends of ropes so as to make a continuous or endlelength without appreciably increasing the diameter. Also making a loop or eye ithe end of a rope by tucking the ends of the strands.



i-

g

-

.

ing

d

d.

ing

Spreader Bar. A member used to make slings vertical from object lifted. Theoretcally a compression member.

Spreader Beam. Same function as spreader bar. Uses less headroom. A bendinmember.

Strand. An arrangement of wires helically laid about an axis, or another wire or fiber center to produce a symmetrical section.

Superstructure. The rotating upper frame structure of the machine and the operating machinery mounted thereon.

Swaged Fittings. Fittings in which wire rope is inserted and attached by swaging

Tackle (Hoist). Assembly of ropes and sheaves arranged for lifting, lowering, or pulling.

Tag Line. A rope used to prevent rotation of a load.

Tail Swing. Distance from center of rotation to maximum rear extension of revolving superstructure.

Thimble. Grooved metal fitting to protect the eye of a wire rope.

Tipping Condition. A machine is considered to be at the point of tipping when abalance is reached between the overturning moment of the load and the stabilizmoment of the machine on a firm level supporting surface.

Tipping Load. Tipping load is the load producing a tipping condition at a specifieradius. It includes the weights of hook, hook blocks, slings, etc., plus weight onhook.

Turnbuckle. Device attached to wire rope for making limited adjustments in length. It consists of a barrel and right-and-left hand threaded bolts.

Whip Line. Secondary rope system. Also see load line.

Wire. Single continuous length of metal, round or shaped, cold drawn from a ro

Wire Rope. A plurality of strands laid helically around an axis or a core.

Wire Strand Core (WSC). Wire strand used as a core for a wire rope.

880 Model SpecificationCIV-MS-4782, Lifting Services, is included in the Specification section of this manual. This model specification establishes the basic requirements for performa lift, including all lift equipment and items required in rigging operations. It alsodiscusses design requirements, inspection and testing, and safety.



890 References

Company Standards1. Safety in Designs Manual, Section 6

American National Standards Institute (ANSI)1. B30.1 Jacks

2. B30.2 Overhead and Gantry Cranes

3. B30.5 Mobile and Locomotive Cranes

4. B30.6 Derricks

5. B30.7 Base Mounted Drum Hoists

6. B30.9 Slings

7. B30.10 Hooks

U.S. Department of Labor, Occupational Safety and Health Administration (OSHA)1. 29CFR1910.180 Crawler Locomotive and Truck Cranes

2. 29CFR1910.181 Derricks

3. 29CFR1910.184 Standard Slings


Documents

800 Cranes, Rigging and Lifting