A.maintain a preset pressure on the line
B.closely regulate the amount of flow
C.relieve excessive pressure on the line
D.allow flow in one direction only
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A.insufficient load
B.excessively high oil viscosity
C.relief-valve pressure setting too high
D.reservoir level being maintained two inches above normal
A.a defective or broken high pressure un-loader
B.a loose valve plate
C.excessive overload
D.no compression
A.regulating the oil flow with the six-way valve
B.moving the automatic differential valve
C.moving the receiving tele-motor which regulates the two-way valve
D.varying the angle of a tilting box or eccentricity of a floating ring
A.Pour point
B.Cloud point
C.Vacuum
D.Pressure
A.set for maximum torque
B.on the purge and vent stroke
C.in the neutral position
D.rotating backwards
最新試題
If the suction pressure at the refrigeration compressor is below normal, the cause can be（）.
If the thermal bulb of an expansion valve is incorrectly placed at the center of the coil instead of the end, it will （）.
The temperature differential occurring between the inlet temperature of the fluid to be cooled and the outlet temperature of the cooling medium in a shell-and-tube heat exchanger is greatest in which of the flow designs listed?（）
A salinity indicator is used to determine the （）.
When the steering gear is in operation, you should （）.
One cause of high head pressure occurring in a refrigeration system can be （）.
The control mode in which the final control element is moved from one of two flexed positions to the other is known as （）.
The amount of fluid friction or internal friction inherent in a mineral lubricating oil is reflected as a measure of its （）.
If the viscosity of the liquid being transferred remains constant as the discharge pressure increases, the rotary pump （）.
Who is responsible for ensuring that someone is assigned to close the watertight doors in an emergency?（）