單項選擇題The oil in a cargo winch gear box should be sampled periodically to ().

A.prevent the gear box from leaking
B.prevent the oil from becoming inflammable
C.make sure it has not become contaminated
D.make sure the motor bearings are lubricated


您可能感興趣的試卷

你可能感興趣的試題

1.單項選擇題A spur gear pump should be operated with the discharge valves ().

A.slightly opened
B.throttled
C.fully opened
D.halfway opened

2.單項選擇題The capacity of a centrifugal pump can be increased by the installation of a larger diameter impeller Another means of increasing the pump capacity is to ().

A.increase speed
B.increase the size of the cardent assembly
C.reduce wearing ring clearances
D.change the pump to a "close coupled" arrangement

3.單項選擇題Which of the following forms of energy is demonstrated through the process of combustion?()

A.Chemical energy
B.Mechanical energy
C.Thermal energy
D.Electrical energy

4.單項選擇題While inspecting the steering system at sea, you should check for ().

A.air bubbles in the sight glass
B.any leaks in the system
C.over-travel in the rudder angle indicator
D.lost motion in the rams

5.單項選擇題Excessive air leakage into the suction side of a centrifugal pump would be indicated by which of the following operational problems?()

A.The pump delivers full capacity when started, but gradually slackens off toan abnormally low flow
B.The pump packing gland overheats after short operating periods
C.The motor over-current protective device continually shuts the pump down
D.Pounding noises can be heard at the pump suction chest