A.3 or 5
B.5 or 7
C.7 or 9
D.9 or 11
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A.sensible heat
B.latent heat
C.total heat
D.residual heat
A.centerline of the pump and the level of the liquid in the suction well when the source of liquid is below the pump
B.centerline of the pump and the suction liquid level when the source of liquid is above the pump
C.centerline of the pump and the level of the discharge liquid
D.liquid levels of the suction and discharge
A.total heat
B.residual heat
C.specific heat
D.superheat
A.Single stage or multistage
B.High pressure or low pressure
C.Open or close coupled
D.Horizontal or vertical
A.contaminated fluid
B.pitted thrust rings
C.worn pintle bearings
D.obstructed suctions passage
最新試題
Low compressor head pressure in a refrigeration system can be caused by（）.
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?（）
Which of the problems listed would came the discharge temperature of an R-12 refrigeration compressor to increase?（）
Pitting in the suction areas of a centrifugal pump bronze impeller is usually caused by （）.
The general purpose of a heat exchanger is to （）.
A gradual decrease in the discharge pressure of an operating hydraulic pump can be caused by （）.
An increasing head pressure in a refrigeration system, without any corresponding change in the cooling water inlet temperature, would probably be caused by （）.
If the suction pressure at the refrigeration compressor is below normal, the cause 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 （）.