默认题库 - 船舶辅助机械

单选题

If your vessel bums 8 tons of fuel per hour at 15 knots, how many tons per hour will it burn at 18 knots?（）

A. 1382 tons
B. 1561 tons
C. 1600 tons
D. 1637 to

单选题

An advantage of a helical gear pump over a simple gear pump is that the helical gear pump is capable of （）.

A. maintaining a steadier speed
B. delivering liquids over greater distances
C. operating for longer periods of time
D. producing a smoother discharge flow

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单选题

Which characteristic or condition will have the greatest effect on increasing a hydraulic oils viscosity?（）

A. Pour point
B. Cloud point
C. Vacuum
D. Pressure

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单选题

Under normal conditions, the refrigerant enters the compressor in an operating refrigeration system as a （）.

A. liquid
B. dry saturated gas
C. wet saturated gas
D. superheated vapor

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单选题

Freon 12 which is used to produce intense cold is normally a （） when at atmospheric pressure and temperature.

A. liquid
B. gas
C. solid
D. water only

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单选题

In motor ship, （） is often used to recover some of the heat carried in the exhaust gases from the main engine.

A. an diesel oil heater
B. a waste heat boiler
C. a fresh water generator
D. all the above

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单选题

Topping wires fix the height of the derricks and （） to the deck may be used to prevent fore and aft movement.

A. stays
B. winches
C. barrels
D. brake

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单选题

In which of the areas listed would you expect to find the highest salt concentration in a flash evaporator?（）

A. Distiller air ejector cooling medium
B. Saltwater heater discharge
C. First-stage internal feed box
D. Second-stage internal feed box

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单选题

Which of the following statements is correct concerning a typical shipboard multi-coil refrigeration system?（）

A. The liquid receiver functions to collect and remove non-condensable gases
B. A thermostatic expansion valve is used to control refrigerated space temperature
C. Refrigerant temperature in an evaporator is directly related to refrigerant pressure
Dehydrators must be used continuously in a refrigeration system

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单选题

The function of the hydraulic telemotor transmitter used in an electro-hydraulic steering gear system is to （）.

A. transmit the rudder angle to the bridge indicator
B. prevent the control linkage from striking the stops when hard over
C. automatically purge all entrained air from the system
D. send hydraulic signals to the receiving unit

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