A.Variable volumes can be obtained with gear pumps only by variation of the pump drive speed
B.A radial piston pump houses sliding pistons in a stationary cylinder block through which passes a rotating pintle or ported shaft
C.The amount of fluid displaced per revolution of an axial piston rotary pump is dependent on the angle formed between the cylinder block and valve plate
D.All of the above
您可能感興趣的試卷
你可能感興趣的試題
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
A.horizontally mounted
B.never fitted with intake filters
C.fitted with intercoolers
D.operated in an unloaded condition at all times
A.High pressure compressors are more efficient than low pressure compressors
B.Mechanical efficiency divided by compressor efficiency will equal the overall efficiency of the compressor unit
C.Two stage compressors are generally more efficient than single stage compressors
D.The volumetric efficiency is decreased in multistage compressors
A.precipitation number
B.neutralization number
C.pour point
D.demulsibility
A.liquid strainer
B.refrigerant inlet of the condenser
C.inlet side of the evaporator
D.suction side of the compressor
最新試題
Heavy wear in a particular area of the inner circumference of a packing ring may be caused by （）.
Who is responsible for ensuring that someone is assigned to close the watertight doors in an emergency?（）
A pressure drop through the refrigerant liquid line may cause （）.
On tank vessels equipped with power operated cargo tank valves, the type of power operator most commonly used is （）.
If the viscosity of the liquid being transferred remains constant as the discharge pressure increases, the rotary pump （）.
If the head pressure of a reciprocating refrigeration compressor is excessive, （）.
An increasing head pressure in a refrigeration system, without any corresponding change in the cooling water inlet temperature, would probably 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 （）.
The rate of heat transfer from a hot region to a cold region is affected most by the （）.
If the relief valve on the discharge side of a hydraulic pump lifts, the cause could be （）.