“Any leaks in piping, propeller shaft, machinery, tanks, will have to be repaired, or at least patched up temporarily until the next stop” This sentence means that （）.

[单选题]Where a propeller shaft passes through the hull，water is prevented from entering by means of a（）.A . stuffing boxB . propeller bossC . seacockD . stop-water

[单选题]The replacement piping for diesel engine high pressure fuel systems must be the same length and diameter as the original piping to （）.A . avoid unnecessary pints inventoryB . keep torsional vibration constantC . use existing supports and bracesD . ma

[单选题]“Piping bag”是指（）。A .挤花袋B .挤花嘴C .面粉袋D .物料袋

[单选题]In the navigation,_______cause the shafting over load most easilyA．stopping the main engine suddenlyB．changing the main engine running direction suddenlyC．the sailing from the shallow water area to the deep water areaD．the ship's trim too much

[单选题]C．ompared to a constant pitch propeller, a controllable pitch propellerA．more efficiently uses available engine powerB．operates at a lower efficiency at a fixed speedC．produces the same torque at lower engine powerD．develops its rated power at a lowe

[单选题]A． controllable pitch propeller on a diesel driven vessel eliminates the need forA．friction clutchesB．disconnect clutchesC．reversing gearsD．reduction gears

[单选题]A variable pitch propeller is made （） a boss with separate blades mounted into it.A . ofB . up ofC . fromD . out

[单选题]The projection on a shaft designed to change circular motion into up and down or back and fore motion is called （）.A . wheelB . crankshaftC . running gearD . cam

[单选题]The （） of the main shaft should be measured with a （）.A . clearance；calipersB . sinking；bridge gaugeC . diameter；bridge gaugeD . clearance；lead wire

[单选题]On opposite ends of a single shaft of a turboblower are a gas driven （）and a air compressor, which are sealed each other.A . charge air receiverB . scavenging air beltC . turbineD . air cooler