A.loss of second stage vacuum
B.contamination of the distillate
C.lower feed inlet temperature
D.contamination of the second stage condenser
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A.total head
B.discharge head
C.net positive suction head
D.suction head
A.slide block
B.tilting box
C.pintle
D.reaction ring
A.Liquids with different viscosities will always have the same specific gravity
B.Liquids with different viscosities will never have the same specific gravity
C.Viscosity and specific gravity are directly proportional
D.Viscosity and specific gravity are not related in that one does not define or limit the other
A.stored at temperatures below 60 degrees Fahrenheit
B.charged into a system having copper fittings
C.allowed to mix with compressor oil
D.exposed to an open flame or hot surface
A.acid formation
B.sludge formation
C.ice in the expansion valve
D.All of the above
最新試題
Which of the following problems could cause the high pressure cutout switch to shut down the compressor in a refrigeration system?（）
If the head pressure of a reciprocating refrigeration compressor is excessive, （）.
Pitting in the suction areas of a centrifugal pump bronze impeller is usually caused by （）.
When the steering gear is in operation, you should （）.
On tank vessels equipped with power operated cargo tank valves, the type of power operator most commonly used is （）.
Which of the listed pumps is NOT a positive displacement pump?（）
If the viscosity of the liquid being transferred remains constant as the discharge pressure increases, the rotary pump （）.
If the suction pressure at the refrigeration compressor is below normal, the cause can be（）.
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?（）
When a refrigeration compressor has developed a high head pressure as a result of a refrigerant overcharge, you should （）.