单选题Stress on the topping lift of a swinging boom can be reduced by（）.Arigging a back stayBraising the boomCincreasing the mechanical advantage of the cargo purchaseDtaking all slack out of the preventer
单选题
Stress on the topping lift of a swinging boom can be reduced by（）.
A
rigging a back stay
B
raising the boom
C
increasing the mechanical advantage of the cargo purchase
D
taking all slack out of the preventer
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Stress on the topping lift of a swinging boom can be reduced by ______.A.rigging a back stayB.raising the boomC.increasing the mechanical advantage of the cargo purchaseD.taking all slack out of the preventer
A band or collar on the top end of a boom to which the topping lift，midships guy，and outboard guys are secured，is called the ______.A.collar bandB.guy bandC.pad eye collarD.spider band
With a given load on the cargo hook，tension in a single span topping lift ______.A.increases as the boom's angle to the horizontal increasesB.is at a maximum when the boom is at a 45° angle to the horizontalC.increases as the boom's angle to the horizontal decreasesD.decreases as the boom's angle to the horizontal decreases
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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
What is meant by the term“luffing the boom”of a crane ________．A.Stopping the boomB.Topping or lowering the boomC.Moving the boom left or rightD.All of the above
Which part provides for transverse control and positioning of a boom in a conventional yard and stay system ________．A.GuyB.ShroudC.SpiderD.Topping lift
As the pace of life continues to increase ,we are fast losing the art of relaxation. Once you are in the habit of rushing through lift,being on the go from morning till night, it is hard to slow down. But relaxation is essential for a healthy mind and body.Stress is an natural part of everyday lift and there is no way to avoid it. In fact ,it is not the bad thing it is often supposed to be .A certain amount of stress is vital to provide motivation adn give purpose to life. It is only when the stress gets out of control that it can lead to poor performance and ill health.The amount of stress a person can withstand depends very much on the individual. Some people are not afraid of stress,and such characters are obviously prime material for managerial responsibilities. Others lose heart at the first signs of unusual difficulties. When exposed to stress,in whatever form,we react both chemically and physically. In fact we make choice between "fight" or "flight" and in more primitive days the choice made the difference between life or death. The crises we meet today are unlikely to be so extreme,but however little the stress,it involves the same response. It is when such a reaction lasts long,through continued exposure to stress,that health becomes endangered.Such serious conditions as high blood pressure and heart disease have established links with stress.Since we cannot remove stress from our lives(it would be unwise to do so even if we could),we need to find ways to deal with it.Which of the follwing statements is ture?a.We can find some ways to avoid stressb.Stress is always harmful to peoplec.It is easy to change the hagit of keeping oneself busy with work.d.Different people can withstand different amounts of stress
The jumbo boom can （）.A、lift heavy cargoB、load and unloadC、join ropes togetherD、lift light cargo
The （）(双杆联吊) is that two booms are used with a single hook.A、derrickB、union purchaseC、topping lift blockD、crane
The （）(千斤滑车) can run the gooseneck.A、heavy derrickB、pulley blockC、topping lift blockD、guy tackle
单选题Which part of a conventional cargo gear rig provides for vertical control and positioning of a boom（）.ACargo whipBGooseneck fittingCSpider bandDTopping lift
单选题A flounder plate，on a topping lift，is（）.Aa fairlead blockBa swivel pin for the topping lift blockCa triangular steel plate with a hole at each cornerDthe lower block of a multiple part topping lift
单选题What is meant by the term TOPPING THE BOOM?（）ALowering the boomBRaising the boomCSpotting the boom over the deckDSwinging the boom athwartships
单选题A band or collar on the top end of a boom which the topping lift, midships guy, and outboard guys are secured, is called the（）.Acollar bandBguy bandCpad eye collarDspider band
单选题Structural stress on a ship can be reduced by（）.Alessening the effect of environmental forcesBeven and symmetrical variable loadingClocal concentration of heavy consumablesDincreasing the metacentric height
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单选题A virtual rise in the center of gravity may be caused by（）.Afilling a partially filled tankBusing an on board crane to lift a freely swinging heavy objectCemptying a partially filled tankDtransferring ballast from the forepeak to the after peak
单选题With a given load on the cargo hook，tension in a single span topping lift（）.Aincreases as the boom's angle to the horizontal increasesBis at a maximum when the boom is at a 45° angle to the horizontalCincreases as the boom's angle to the horizontal decreasesDdecreases as the boom's angle to the horizontal decreases
单选题The majority of cargo gear breakdowns are a result of（）.AGuy failuresBTopping lift failuresCBending of the boom from compressionDGooseneck failure
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
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