A.molecular fluid vibration
B.energy losses
C.wide pressure variations
D.mechanical damage to control valves
您可能感興趣的試卷
你可能感興趣的試題
A.Keeps the refrigerated space cooler
B.Reduces the efficiency of the plant
C.Takes the load off the compressor
D.Has no affect on the system
A.proportional band
B.the error signal
C.the reset signal
D.feedback
A.Dehydrators must be used continuously in a refrigeration system
B.A 25 ton refrigeration system has the same cooling effect as melting 25 tons of ice in 24 hours
C.A thermostatic expansion valve is used to control refrigerated space temperature
D.The liquid receiver functions to collect and remove non- condensable gases
A.Hydraulic
B.Mechanical
C.Pneumatic
D.Electrical
A.Energy can be created or destroyed
B.Energy may not be transformed
C.The total quantity of energy in the universe is always the same
D.None of the above
最新試題
If you are given the job of adding hydraulic fluid to a mooring winch, and are not certain as to the type of fluid to use, you should （）.
Which of the following statements is correct concerning heat transfer?（）
The usual symptoms of cavitation in a centrifugal pump is （）.
A pressure drop through the refrigerant liquid line may cause （）.
If the relief valve on the discharge side of a hydraulic pump lifts, the cause could be （）.
Heavy wear in a particular area of the inner circumference of a packing ring may be caused by （）.
The rate of heat transfer from a hot region to a cold region is affected most by the （）.
Who is responsible for ensuring that someone is assigned to close the watertight doors in an emergency?（）
The general purpose of a heat exchanger is to （）.
The major source of chemical contaminants in hydraulic fluid is （）.