A.warm-up allows the hydraulic system to become charged with oil
B.warm-up allows the relief valves to be properly tested
C.hydraulic strainers operate only during the warm-up period
D.hydraulic fluid must be at the proper viscosity
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A.are exposed to a vacuum
B.come in contact with extremely hot surfaces
C.are reduced in temperature to just above the pour point
D.become extremely agitated or aerated
A.weight
B.internal friction
C.demulsibility
A.Extensive centrifuging
B.Wax content
C.Water content
D.Acid content
A.Viscosity will increase as temperature increases
B.Viscosity is a measure of a fluid s internal resistance to flow
C.Viscosity will decrease as temperature decreases
D.Viscosity is not dependent on temperature
A.the manual trick wheel is engaged for steering
B.the variable stroke pump is off stroke
C.a rudder order is given by the control system
D.an electric power system failure occurs at the steering gear
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On tank vessels equipped with power operated cargo tank valves, the type of power operator most commonly used is （）.
If the relief valve on the discharge side of a hydraulic pump lifts, the cause could be （）.
An increasing head pressure in a refrigeration system, without any corresponding change in the cooling water inlet temperature, would probably be caused by （）.
The usual symptoms of cavitation in a centrifugal pump is （）.
A pressure drop through the refrigerant liquid line may cause （）.
Low compressor head pressure in a refrigeration system can be caused by（）.
The control mode in which the final control element is moved from one of two flexed positions to the other is known as （）.
Which of the problems listed would came the discharge temperature of an R-12 refrigeration compressor to increase?（）
The amount of fluid friction or internal friction inherent in a mineral lubricating oil is reflected as a measure of its （）.
Which of the following statements is correct concerning heat transfer?（）