A.the pressure regulating valve is not closing
B.an excessive lack of refrigerant in the system
C.badly leaking discharge valves
D.worn piston rings
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A.Both are higher than normal burning temperatures
B.The flash point is always higher
C.The ignition temperature is always higher
D.They are not necessarily related
A.tend to twist about its long axis
B.expand in length and in diameter
C.contract in length and expand in diameter
D.flex at right angles to the applied pressure
A.holding the discharge valve open
B.relieving the intercooler pressure to the atmosphere
C.using an enlarged, permanently opened clearance expansion space
D.a pre-charged accumulator
A.within the space concerned
B.outside the space concerned
C.the throttle station
D.within the fire room
A.leaking discharge valve
B.jammed suction valve
C.tripped overload relay
D.broken discharge un-loader
最新試題
Who is responsible for ensuring that someone is assigned to close the watertight doors in an emergency?（）
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If the thermal bulb of an expansion valve is incorrectly placed at the center of the coil instead of the end, it will （）.
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Which of the listed pumps is NOT a positive displacement pump?（）
The amount of fluid friction or internal friction inherent in a mineral lubricating oil is reflected as a measure of its （）.
One cause of high head pressure occurring in a refrigeration system can be （）.
The usual symptoms of cavitation in a centrifugal pump is （）.
The output volume of a positive fixed displacement pump can be changed only by （）.