The greatest strain，when lifting a load with the jumbo purchase，is on ______．A.all of the parts，dividing the load equallyB.the hauling part because it must absorb the frictional losses of all the sheavesC.the parts in the movable blockD.the standing part because it is directly connected to the weight
The greatest strain，when lifting a load with the jumbo purchase，is on ______．
A.all of the parts，dividing the load equally
B.the hauling part because it must absorb the frictional losses of all the sheaves
C.the parts in the movable block
D.the standing part because it is directly connected to the weight
相关考题：
What feature of “body language”mentioned in the passage is common to both humans and animals?A.Lifting beads when sad.B.Keeping long faces when angry.C.Bristling hair when ready to attack.D.Bowing heads when willing to obey.
To safeguard the operator and other personnel working on or near a hoisting operation, which of the following precautions should be observed?A.Keep a load on the hoist until all personnel are finished workingB.Set the load on a movable dolly when transportation may be neededC.Have one man keep a hand on the load to steady itD.Insure that the lifting gear capacity is not exceeded
Among the rings of a piston the ______one is subjected to the greatest load and temperature.A.bottomB.middleC.topD.any position
Which safety precaution（s）should be observed during crane operations ________．A.Checking for proper lifting from beneath the load during cargo operationsB.Using the proper slings or other lifting devices during cargo operationsC.Relaying communications to port agents on the pier during cargo hoistsD.All of the above
The preventer guy，as used on a conventional yard and stay rig，______．A.Is rigged at an angle of 70° to 90° from the guy it assistsB.Takes the strain imposed on the schooner guy when burtoning cargoC.Is rigged when lifting cargo that exceeds the SWL of a single whipD.Should take the strain if the regular guy parts
For any given pedestal crane，when the boom is lengthened，the lifting capacity is ______．A.unchangedB.increasedC.eliminatedD.decreased
What does “evel-luffing” accomplish during crane operations ________．A.It prevents the load from swinging when the boom level is adjustedB.Less power is needed when topping the boom with a load on the hookC.It maintains the height of the load above the deckD.All of the above
When loading a tanker，you should ______．A.load only one tank at a timeB.keep the seamen on watch on standby in the mess roomC.keep a strain on the loading hosesD.close valves by closing them down，reopening one or two turns，and re-closing
An on-load release system on a survival craft means the cable can be released ______.A.only when the load is taken off the cableB.only when there is a load on the cableC.only when activated by the controls at the lowering stationD.at any time
The jumbo boom can （）.A、lift heavy cargoB、load and unloadC、join ropes togetherD、lift light cargo
The （）(浮吊) can float on water used to load and unload the cargo.A、floating craneB、jumbo boomC、union purchaseD、crane
单选题In cargo crane, （） for lifting the load.Aa hoisting motorBa luffing motorCa mooring motorDa slewing motor
单选题When the derrick changes its （）(角度), its lifting capacity changes correspondingly.AangelBlengthCheightDangle
单选题Generally, when lifting an inflatable life raft back aboard ship you would use the（）.Atowing bridleBmain weather coverCexternal lifelinesDrighting strap
单选题For any given pedestal crane，when the boom is lengthened，the lifting capacity is（）.AunchangedBincreasedCeliminatedDdecreased
单选题The greatest strain，when lifting a load with the jumbo purchase，is on（）.Aall of the parts，dividing the load equallyBthe hauling part because it must absorb the frictional losses of all the sheavesCthe parts in the movable blockDthe standing part because it is directly connected to the weight
单选题The force acting on a single cargo runner which is vertically lifting or lowering a load is greatest when（）.Adecelerating when lowering the loadBdecelerating when raising the loadClowering the load at constant speedDraising the load at constant speed
单选题Any friction fit, tightness or adhesion of the part of any load being lifted should be broken by wedge or tapping and not by increasing the load on the applianceAccording to this sentence, （）Athe lifting appliance can always lift the freight within its rated loadBattention should be paid in order not to break the wedge when lifting cargoCsometimes the lifting work needs other assistance other than the lifting applianceDlifting work should be done with every part fit, tightness or adhesion
单选题To safeguard the operator and other personnel working on or near a hoisting operation which of the following precautions should be observed?（）AKeep a load on the hoist until all personnel are finished workingBSet the load on a movable dolly when transportation may be neededCHave one man keep a hand on the load to steady itDInsure that the lifting gear capacity is not exceeded
单选题The preventer guy，as used on a conventional yard and stay rig，（）.Ais rigged at an angle of 70°to 90°from the guy it assistsBtakes the strain imposed on the schooner guy when burtoning cargoCis rigged when lifting cargo that exceeds the SWL of a single whipDshould take the strain if the regular guy parts
单选题A spreader bar is used to（）.Aincrease the lifting capacityBincrease the lifting radiusCprotect the slingsDprotect the upper part of a load
单选题An on-load release system on a survival craft means the cable can be released（）.Aonly when the load is taken off the cableBonly when there is a load on the cableConly when activated by the controls at the lowering stationDat any time
单选题What does “evel-luffing” accomplish during crane operations（）.AIt prevents the load from swinging when the boom level is adjustedBLess power is needed when topping the boom with a load on the hookCIt maintains the height of the load above the deckDAll of the above
单选题Generally，when lifting an inflatable liferaft back aboard ship you would use the（）.Atowing bridleBmain weather coverCexternal lifelinesDrighting strap