Lifting and Moving Equipment Section I. Lifting Equipment

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C H A P T E R 5

L i f t i n g a n d M o v i n g E q u i p m e n t

Section I. Lifting Equipment

Equipment used for lifting includes gin includes pole, brave, and jinniwink der-poles, tripods, shears, boom derricks, and ricks.stiff leg derricks. Light hoisting equipment

GIN POLESA gin pole consists of an upright spar that isguyed at the top to maintain it in a verticalor nearly vertical position and is equippedwith suitable hoisting tackle. The verticalspar may be of timber, a wide-flange steel-beam section, a railroad rail, or similarmembers of sufficient strength to supportthe load being lifted. The load may behoisted by hand tackle or by hand- orengine-driven hoists. The gin pole is usedwidely in erection work because of the easewith which it can be rigged, moved, andoperated. It is suitable for raising loads ofmedium weight to heights of 10 to 50 feetwhere only a vertical lift is required. Thegin pole may also be used to drag loads hori-zontally toward the base of the pole whenpreparing for a vertical lift. It cannot bedrifted (inclined) more than 45 degrees fromthe vertical or seven-tenths the height ofthe pole, nor is it suitable for swinging theload horizontally. The length and thicknessof the gin pole depends on the purpose forwhich it is installed. It should be no longerthan 60 times its minimum thicknessbecause of its tendency to buckle under com-pression. A usable rule is to allow 5 feet ofpole for each inch of minimum thickness.Table 5-1, page 5-2, lists values when using

spruce timbers as gin poles, with allow-ances for normal stresses in hoisting oper-ations.

RIGGING GIN POLES

In rigging a gin pole, lay out the pole withthe base at the spot where it is to beerected. To make provisions for the guylines and tackle blocks, place the ginpole on cribbing for ease of lashing. Figure4-18, page 4-16, shows the lashing on top ofa gin pole and the method of attachingguys. The procedure is as follows:

Make a tight lashing of eight turns offiber rope about 1 foot from the top ofthe pole, with two of the center turnsengaging the hook of the upper blockof the tackle. Secure the ends of thelashing with a square knot. Nailwooden cleats (boards) to the poleflush with the lower and upper sidesof the lashing to prevent the lashingfrom slipping.

Lay out guy ropes, each four times thelength of the gin pole. In the center ofeach guy rope, form a clove hitch over

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the top of the pole next to the tacklelashing. Be sure to align the guy linesin the direction of their anchors (seeFigure 5-1).

Lash a block to the gin pole about 2 feetfrom the base of the pole, the same asfor the tackle lashing at the top, andplace a cleat above the lashing to pre-vent slipping. This block serves as aleading block on the fall line, whichallows a directional change of pull fromthe vertical to the horizontal. A snatchblock is the most convenient type to usefor this purpose.

Reeve the hoisting tackle, and use theblock lashed to the top of the pole sothat the fall line can be passed throughthe leading block at the base of the ginpole.

Drive a stake about 3 feet from thebase of the gin pole. Tie a rope fromthe stake to the base of the pole below

the lashing on the leading block andnear the bottom of the pole. This pre-vents the pole from skidding while youerect it.

Check all lines to be sure that they arenot snarled. Check all lashings to seethat they are made up properly andthat all knots are tight. Check thehooks on the blocks to see that they aremoused properly. You are now readyto erect the gin pole.

ERECTING GIN POLESYou can easily raise a 40-foot-long gin poleby hand (see Figure 5-2). However, youmust raise longer poles by supplementaryrigging or power equipment. The number ofpeople needed to erect a gin pole depends onthe weight of the pole. The procedure is asfollows:

Dig a hole about 2 feet deep for thebase of the gin pole.

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String out the guys to their respectiveanchorages and assign a person to eachanchorage to control the slack in theguy line with a round turn around theanchorage as the pole is raised. If ithas not been done already, install ananchorage for the base of the pole.

Use the tackle system that was used toraise and lower the load to assist inraising the gin pole, if necessary; how-ever, the preferred method is to attachan additional tackle system to the rearguy line. Attach the running block ofthe rear guy-line tackle system to therear guy line, the end of which is at thispoint of erection near the base of thegin pole (see Figure 4-18, page 4-16).Secure the fixed or stationary block tothe rear anchor. The fall line shouldcome out of the running block to givegreater MA to the tackle system.Stretch the tackle system to the base ofthe gin pole before erecting it to pre-vent the tackle blocks from chocking.

Haul in on the fall line of the tacklesystem, keeping a slight tension on therear guy line and on each of the sideguy lines, while eight people (more forlarger poles) raise the top of the pole byhand until the tackle system can takecontrol (see Figure 5-2, page 5-3).

Keep the rear guy line under tension toprevent the pole from swinging and

throwing all of its weight on one of theside guys.

Fasten all guy lines to their anchor-ages with the round turn and two halfhitches when the pole is in its finalposition, approximately vertical orinclined as desired. At times, you mayhave to double the portion of rope usedfor the half hitches.

Open the leading block at the base ofthe gin pole and place the fall line fromthe tackle system through it. Whenthe leading block is closed, the gin poleis ready for use. If you have to driftthe top of the pole without moving thebase, do it when there is no load onthe pole, unless the guys are equippedwith tackle.

OPERATING GIN POLESThe gin pole is particularly adapted to verti-cal lifts (see Figure 5-3). Sometimes it isused for lifting and pulling at the same timeso that the load being moved travels towardthe gin pole just off the ground. When usedin this manner, attach a snubbing line ofsome kind to the other end of the load beingdragged; keep it under tension at all times.Use tag lines to control loads that you arelifting vertically. A tag line is a light linefastened tounder slight

one end of the load and kepttension during hoisting.

TRIPODSA tripod consists of three legs lashed or one-half times that of shears made of thesecured at the top. The advantage of the tri- same size material.pod over other rigging installations is thatit is stable and requires no guy lines tohold it in place. Its disadvantage is that the RIGGING TRIPODS

load can be moved only up and down. The The two methods of lashing a tripod, eitherload capacity of a tripod is about one and of which is suitable provided the lashing

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material is strong enough, are discussedbelow. The material used for lashing can befiber rope, wire rope, or chain. Metal ringsjoined with short chain sections and largeenough to slip over the top of the tripod legsalso can be used.

Method 1

This method is for fiber rope, 1 inch in diam-eter or smaller. Since the strength of the tri-pod is affected directly by the strength of therope and the lashing used, use more turnsthan described here for extra heavy loadsand fewer turns for light loads. The proce-dure is as follows:

Select three spars, about equal in size,and place a mark near the top of eachto indicate the center of the lashing.

Lay two of the spars parallel with theirtops resting on a skid or block and athird spar between the first two, withthe butt in the opposite direction andthe lashing marks on all three in line.The spacing between spars should beabout one-half the diameter of thespars. Leave space between the sparsso that the lashing will not be drawntoo tight when erecting the tripod.

Make a clove hitch (using a l-inchrope) around one of the outside sparsabout 4 inches above the lashing mark,and take eight turns of the line aroundthe three spars (see Figure 5-4, A). Besure to maintain the space between thespars while making the turns.

Finish the lashing by taking two closefrapping turns around the lashingbetween each pair of spars. Secure theend of the rope with a clove hitch onthe center spar just above the lashing.Do not draw the frapping turns tootight.

Method HYou can use this method when using slenderpoles that are not more than 20 feet long orwhen some means other than hand power isavailable for erection (see figure 5-4, B). Theprocedure is as follows:

Lay the three spars parallel to eachother with an interval between themslightly greater than twice the diame-ter of the rope you use. Rest the tops ofthe poles on a skid so that the endsproject over the skid about 2 feet andthe butts of the three spars are in line.Put a clove hitch on one outside leg atthe bottom of the position that the lash-ing will occupy, which is about 2 feet


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from the end. Weave the line over themiddle leg, under and around the outerleg, under the middle leg, and over andaround the first leg; continue thisweaving for eight turns. Finish with aclove hitch on the outer leg.

ERECTING TRIPODS

Spread the legs of a tripod in its final posi-tion so that each leg is equidistant from theothers (see Figure 5-5). This spread shouldnot be less than one-half nor more than two-thirds of the length of the legs. Use chain,rope, or boards to hold the legs in this posi-tion. You can lash a leading block for the fallline of the tackle to one of the legs. The pro-cedure is as follows:

Raise the tops of the spars about 4 feet,keeping the base of the legs on theground.

Cross the two outer legs. The third orcenter leg then rests on top of the cross.With the legs in this position, pass asling over the cross so that it passesover the top or center leg and aroundthe other two.

Hook the upper block of a tackle to thesling and mouse the hook.

Continue raising the tripod by pushingin on the legs as they are lifted at thecenter. Eight people should be able toraise an ordinary tripod into position.

Place a rope or chain lashing betweenthe tripod legs to keep them from shift-ing once they are in their final position.

ERECTING LARGE TRIPODSFor larger tripod installations, you may haveto erect a small gin pole to raise the tripodinto position. Erect the tripods that arelashed in the manner described in Method II

(with the three legs laid together) by raisingthe tops of the legs until the legs clear theground so they can be spread apart. Useguy lines or tag lines to assist in steadyingthe legs while raising them. Cross the outerlegs so that the center leg is on top of thecross, and pass the sling for the hoistingtackle over the center leg and around thetwo outer legs at the cross.


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SHEARSShears made by lashing two legs togetherwith a rope are well adapted for liftingheavy machinery or other bulky loads. Theyare formed by two members crossed at theirtops, with the hoisting tackle suspendedfrom the intersection. Shears must beguyed to hold them in position. Shears arequickly assembled and erected. Theyrequire only two guys and are adapted toworking at an inclination from the vertical.The legs of the shears may be round poles,timbers, heavy planks, or steel bars, depend-ing on the material at hand and the purposeof the shears. In determining the size of themembers to use, the load to be lifted and theratio (L/d) of the legs are the determiningfactors. For heavy loads, the L/d should notexceed 60 because of the tendency of the legsto bend rather than to act as columns. Forlight work, you can improvise shears fromtwo planks or light poles bolted together andreinforced by a small lashing at the intersec-tion of the legs.

RIGGING SHEARSWhen the shears are erected, the spread ofthe legs should equal about one-half theheight of the shears. The maximum allow-able drift is 45 degrees. Tackle blocks andguys for shears are essential. You cansecure the guy ropes to firm posts or treeswith a turn of the rope so that the length ofthe guys can be adjusted easily. The proce-dure is as follows:

Lay two timbers together on theground in line with the guys, with thebutt ends pointing toward the back guyand close to the point of erection.

Place a large block under the tops ofthe legs just below the point of lashingand insert a small spacer blockbetween the tops at the same point (seeFigure 5-6). The separation between

the legs at this point should be equal toone-third the diameter of one leg tomake handling of the lashing easier.

With sufficient l-inch rope for 14 turnsaround both legs, make a clove hitcharound one spar and take eight turnsaround both legs above the clove hitch(see Figure 5-6). Wrap the turnstightly so that the lashing is smoothand without kinks.

Finish the lashing by taking two frap-ping turns around the lashing betweenthe legs and securing the end of therope to the other leg just below thelashing. For handling heavy loads,increase the number of lashing turns.

ERECTING SHEARS

Dig the holes at the points where the legs ofthe shears are to stand. If placed on rockyground, make sure that the base for theshears is level. Cross the legs of the shearsand place the butts at the edges of the holes.With a short length of rope, make two turnsover the cross at the top of the shears and tiethe rope together to form a sling. Be sure tohave the sling bearing against the spars andnot on the shears lashing entirely. The pro-cedure is as follows:

Reeve a set of blocks and place thehook of the upper block through thesling. Secure the sling in the hook bymousing. Fasten the lower block to oneof the legs near the butt so that it willbe in a convenient position when theshears have been raised but will be outof the way during erection.

Rig another tackle in the back guy nearits anchorage if you use the shears onheavy lifts. Secure the two guys to the


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top of the shears with clove hitches tolegs opposite their anchorages abovethe lashing.

Lift the top end of the shears legs and“walk” them up by hand until thetackle on the rear guy line can takeeffect (see Figure 5-7, page 5-10). Itwill take several people (depending onthe size of the shears) to do this. Thenraise the shears legs into final positionby hauling in on the tackle. Secure thefront guy line to its anchorage beforeraising the shears legs, and keep aslight tension on this line to controlmovement.

Keep the legs from spreading by con-necting them with rope, a chair, orboards. It may be neceesary, undersome conditions, to anchor each leg ofthe shears while erecting them to keepthe legs from sliding in the wrongdirection.

OPERATING SHEARSThe rear guy is a very important part of theshears rigging, since it is under a consider-able strain during hoisting. To avoid guy-line failure, design them according to theprinciples discussed in Chapter 4, Section II.The front guy has very little strain on it and


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is used mainly to aid in adjusting the loads, the fall line of the tackle of the shearsdrift and to steady the top of the shears can be led straight out of the upper block.when hoisting or placing the load. You may When handling heavy loads, you may havehave to rig a tackle in the rear guy for to lash a snatch block near the base of one ofhandling heavy loads. During opera- the shear legs to act as a leading block (seetion, set the desired drift by adjusting Figure 5-8). Run the fall line through thethe rear guy, but do not do this while a leading block to a hand- or power-operatedload is on-the shears. For handling light winch for heavy loads.


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BOOM DERRICKS

A boom derrick is a lifting device that incor- swing more than 180 degrees when it is setporates the advantages of a gin pole and the on a turn plate or turn wheel.long horizontal reach of a boom. Use theboom derrick to lift and swing medium-size RIGGING BOOM DERRICKSloads in a 90-degree arc on either side of theresting position of the boom, for a total For hoisting medium loads, rig a boom to

swing of 180 degrees. When employing a swing independently of the pole. Take

boom derrick in lifting heavy loads, set it oncare to ensure the safety of those using theinstallation. Use a boom only temporarily

a turn plate or turn wheel to allow the mast or when time does not permit a more sta-and boom to swing as a unit. A mast is a ble installation. When using a boom on agin pole used with a boom. The mast can gin pole, more stress is placed on the rear


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guy; therefore, you may need a stronger guy.In case larger rope is not at hand, use a setof tackle reeved with the same size rope asthat used in the hoisting tackle as a guy lineby extending the tackle from the top of thegin pole to the anchorage. Lash the blockattached to the gin pole at the point wherethe other guys are tied and in the samemanner. The procedure is as follows:

Rig a gin pole as described on page 5-1,but lash another block about 2 feetbelow the tackle lashing at the top ofthe pole (see Figure 5-9). Reeve thetackle so that the fall line comes fromthe traveling block instead of thestanding block. Attach the travelingblock to the top end of the boom aftererecting the gin pole.

Erect the gin pole in the mannerdescribed on page 5-1, but pass the fallline of the tackle through the extrablock at the top of the pole before erect-ing it to increase the MA of the tacklesystem.

Select a boom with the same diameterand not more than two-thirds as longas the gin pole. Spike two boards to thebutt end of the boom and lash themwith rope, making a fork (see Figure5-9). Make the lashing with a mini-mum of sixteen turns and tie it off witha square knot. Drive wedges under thelashing next to the cleats to help makethe fork more secure (see Figure 5-9).

Spike cleats to the mast about 4 feetabove the resting place of the boom andplace another block lashing just abovethese cleats. This block lashing willsupport the butt of the boom. If a sepa-rate tackle system is rigged up to sup-port the butt of the boom, place anadditional block lashing on the boomjust below the larger lashing to securethe running block of the tackle system.

Use manpower to lift the boom in placeon the mast through the sling that willsupport it if the boom is light enough.The sling consists of two turns of ropewith the ends tied together with asquare knot. The sling should passthrough the center four turns of theblock lashing on the mast and shouldcradle the boom. On heavier booms,use the tackle system on the top of themast to raise the butt of the boom tothe desired position onto the mast.

Lash the traveling block of the gin poletackle to the top end of the boom asdescribed on page 5-1, and lash thestanding block of the boom tackle atthe same point. Reeve the boom tackleso that the fall line comes from thestanding block and passes through theblock at the base of the gin pole. Theuse of the leading block on this fall lineis optional, but when handling heavyloads, apply more power to a horizontalline leading from the block with lessstrain on the boom and guys.


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ERECTING BOOM DERRICKS

Raise the boom into position when the rig-ging is finished. When working with heavyloads, rest the base of the boom on theground at the base of the pole. Use a morehorizontal position when working with lightloads. In no case should the boom bearagainst any part of the upper two-thirds ofthe mast.

OPERATING BOOM DERRICKS

A boom on a gin pole provides a convenientmeans for loading and unloading trucks or

STIFF-LEGThe mast of a stiff-leg derrick is held in thevertical position by two rigid, inclined strutsconnected to the top of the mast. The strutsare spread 60 to 90 degrees to provide sup-port in two directions and are attached tosills extending from the bottom of the mast.The mast is mounted on vertical pins. Themast and boom can swing through an arc ofabout 270 degrees. The tackles for hoistingthe load and raising the boom are similar tothose used with the boom and gin pole (seepage 5-11, Rigging Boom Derrick).

OPERATING STIFF-LEG DERRICKSA stiff-leg derrick equipped with a long boomis suitable for yard use for unloading andtransferring material whenever continuousoperations are carried on within reach of itsboom. When used on a bridge deck, movethese derricks on rollers. They are sometimesused in multistory buildings surmounted bytowers to hoist material to the roof of themain building to supply guy derricks

flatcars when the base of the gin pole cannotbe set close to the object to be lifted. It isused also on docks and piers for unloadingboats and barges. Swing the boom by push-ing directly on the load or by pulling theload with bridle lines or tag lines. Adjustthe angle of the boom to the mast by haulingon the fall line of the mast tackle. Raise orlower the load by hauling on the fall line ofthe boom tackle. You should place a leadingblock (snatch block) at the base of the ginpole. Lead the fall line of the boom tacklethrough this leadingpower-operated winching of the load.

DERRICKSmounted on the tower.

block to a hand- orfor the actual hoist-

The stiff-leg derrickalso is used where guy lines cannot be pro-vided, as on the edge of a wharf or on abarge.

STEEL DERRICKSSteel derricks of the stiff-leg type are avail-able to engineer troops in two sizes:

A 4-ton rated capacity with a 28-footradius (see Figure 5-10, page 5-14).

A 30-ton rated capacity with a 38-footradius, when properly counter-weighted.

Both derricks are erected on fixed bases.The 4-ton derrick, including a skid-mounted, double-drum, gasoline-engine-driven hoist, weighs 7 tons and occupies aspace 20 feet square. The 30-ton derrick,including a skid-mounted, double-drumhoist, weighs about 22 tons and occupies aspace 29 feet square.

LIGHT HOISTING EQUIPMENTExtended construction projects usually in- members by hand or by light hoisting equip-volve erecting numerous light members as ment, allowing the heavy hoisting equip-well as the heavy main members. Progress ment to move ahead with the erection of thecan be more rapid if you raise the light main members. Very light members can be


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raised into place by two people using manila POLE DERRICKShandlines. When handlines are inadequate The improved pole derrick, called a “dutch-or when members must be raised above the man”, is essentially a gin pole constructedworking level, use light hoisting equipment.Many types of hoisting equipment for lifting

with a sill and knee braces at the bottom(see Figure 5-11, A). It is usually installed

light loads have been devised. Those dis- with guys at the front and back. It is effec-cussed here are only typical examples that tive for lifting loads of 2 tons and, becausecan be constructed easily in the field and of its light weight and few guys, is readilymoved readily about the job. moved from place to place by a small squad.


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BRAVE DERRICKSThe braced derrick, known as a “monkey”, isvery useful for filling in heavy membersbehind the regular erection equipment (seeFigure 5-11, B, page 5-15). Two back guysare usually employed when lifting heavyloads, although light members may be liftedwithout them. Power is furnished by ahand- or power-driven hoist. The construc-tion of the base of the monkey permits it tobe anchored to the structure by lashings toresist the pull of the lead line on the snatchblock at the foot of the mast.

JINNIWINK DERRICKSThis derrick is suitable for lifting loadsweighing 5 tons (see Figure 5-11, C, page5-15). Hand-powered jinniwinks arerigged preferably with manila rope. Thoseoperated by a power-driven hoist shouldbe rigged with wire rope, The jinniwinkis lashed down to the structural frame atboth the front sill and tail sill to preventthe tail sill from rising when a load islifted.

Section II. Moving EquipmentSkids, rollers and jacks are used to move (see Figure 5-12). A firm and level founda-heavy loads. Cribbing or blocking is often tion for cribbing is essential, and the bottomnecessary as a safety measure to keep an timbers should rest firmly and evenly onobject in position or to prevent accidents to the ground. Blocking used as a foundationpeople who work under or near these heavy for jacks should be sound and large enoughobjects. Cribbing is formed by piling tim- to carry the load. The timbers should bebers in tiers, with the tiers alternating in dry, free from grease, and placed firmly ondirection, to support a heavy weight at a the ground so that the pressure is evenlyheight greater than blocking would provide distributed.

SKIDSPlace timber skids longitudinally under Oak planks 2 inches thick and about 15 feetheavy loads either to— long make satisfactory skids for most opera-

Distribute the weight over a greater tions. Keep the angle of the skids low to pre-area. vent the load from drifting or getting out of

control. You can use grease on skids whenMake a smooth surface for skidding only horizontal movement is involved; how-equipment. ever, in most circumstances, greasing is dan-Provide a runway surface when rollers gerous because it may cause the load to driftare used (see Figure 5-13). sideways suddenly.

ROLLERS

Use hardwood or pipe rollers over skids for round and long enough to pass completelymoving very heavy loads into position. under the load being moved. Support thePlace the skids under the rollers to provide a load on longitudinal wooden members tosmooth, continuous surface for the rollers. provide a smooth upper surface for the rollersMake sure that the rollers are smooth and to move on. The skids placed underneath


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the rollers must form continuous support.Ordinarily, place four to six rollers under theload to be moved (see Figure 5-13, page 5-17).

Place several rollers in front of the load androll the load slowly forward onto the rollers.As the load passes, rollers are left clearbehind the load and are picked up and placedin front of the load so that there is a continu-ous path of rollers. In making a turn with aload on rollers, incline the front rollersslightly in the direction of the turn and therear rollers in the opposite direction. Thisinclination of the rollers may be made bystriking them sharply with a sledge. Formoving lighter loads, make up the rollers andset on axles in side beams as a semiperma-nent conveyor. Permanent metal roller con-veyors are available (see Figure 5-14). Theyare usually made in sections.

JACKS

To place cribbing, skids, or rollers, you mayhave to lift and lower the load for a shortdistance. Jacks are used for this purpose.Jacks are used also for precision placementof heavy loads, such as bridge spans. Anumber of different styles of jacks are avail-able, but only use heavy duty hydraulic orscrew-type jacks. The number of jacks usedwill depend on the weight of the load andthe rated capacity of the jacks. Be certainthat the jacks are provided with a solid foot-ing, preferably wooden blocking. Cribbingis frequently used in lifting loads by jackingstages (see Figure 5-15). The procedurerequires—

Blocking the jacks.

Raising the object to the maximumheight of the jacks to permit cribbingto be put directly under the load.

Lowering the load onto the cribbing.

Repeat this process as many times as nec-essary to lift the load to the desired height.

Jacks are available in capacities from 5 to100 tons (see Figure 5-16). Small capacityjacks are operated through a rack bar orscrew, while those of large capacity areusually operated hydraulically.

RATCHET-LEVER JACKSThe ratchet lever jack, available to engi-neer troops as part of panel bridge equip-ment, is a rack-bar jack that has a ratedcapacity of 15 tons (see Figure 5-16, A). Ithas a foot lift by which loads close to itsbase can be engaged. The foot capacity is 71/2 tons.


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STEAMBOAT RATCHETS

Their principal uses are for tightening linesor lashings and for spreading or bracingparts in bridge construction.

SCREW JACKSScrew jacks have a rated capacity of 12 tons(see Figure 5-16, C). They are about 13 incheshigh when closed and have a safe rise of atleast 7 inches. These jacks are issued withthe pioneer set and can be used for generalpurposes, including steel erection.

HYDRAULIC JACKSHydraulic jacks are available in Class IVsupplies in capacities up to 100 tons (seeFigure 5-16, D) Loads normally encounteredby engineer troops do not require large.

Steamboat ratchets (sometimes called push- capacity hydralic jacks. Those supplieding-and-pulling jacks) are ratchet screw with the squad pioneer set are 11 inchesjacks of 10-ton rated capacity with end fit- high and have a rated capacity of 12 tonstings that permit pulling parts together or and a rise of at least 5 1/4 inches. They arepushing them apart (see Figure 5-16, B). large enough for usual construction needs.


Documents

Lifting and Moving Equipment Section I. Lifting Equipment