单选题Increasing the speed of a rotary pump above its rated speed will result in which of the following conditions to occur?（）A Loss of suctionB Increased clearancesC Decreased clearanceD Decreased slippage

The amount of fluid delivered by a positive displacement pump can be regulated by _____.

A.throttling the pressure line

B.changing the speed of the driving rotor

C.either A or B

D.None of the above is tree

Which method should be used to warm up the pump turbines prior to discharge ________．

A.Lock the turbine rotor and slowly bleed in steam until operating temperature is reached

B.Run the pump at high speed with the discharge valves closed

C.Run the turbine at slow speed with the pump disconnected

D.Shut the discharge valve and run the pump at slow speed

A.going

B.advancing

C.progressing

D.moving

An over-speed safety device is usually fitted to a generator engine for ___ in the event of over-speed.

A.stabilizing the ship speed

B.increasing the fuel pump setting

C.braking the crankshaft

D.cutting power off the engine

Which pump must always be primed ________．

A.Centrifugal pump

B.Reciprocating pump

C.Rotary pump

D.All of the above

Compared to a constant pitch propeller, a controllable pitch propeller

A.more efficiently uses available engine power

B.operates at a lower efficiency at a fixed speed

C.produces the same torque at lower engine power

D.develops its rated power at a lower speed