A.acid formation
B.sludge formation
C.ice in the expansion valve
D.All of the above
您可能感興趣的試卷
你可能感興趣的試題
A.superheated outside the system
B.in contact with an open flame
C.heated to the boiling point
D.All of the above
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
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
最新試題
If the head pressure of a reciprocating refrigeration compressor is excessive, ().
Which of the listed pumps is NOT a positive displacement pump?()
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 ().
The output volume of a positive fixed displacement pump can be changed only by ().
When the steering gear is in operation, you should ().
The general purpose of a heat exchanger is to ().
A grease gun is generally used to lubricate a ().
Low compressor head pressure in a refrigeration system can be caused by().
When a refrigeration compressor has developed a high head pressure as a result of a refrigerant overcharge, you should ().