A.They make it easier to replace the pump shaft packing
B.They can be economically replaced as they wear out
C.They can be removed when it is necessary to lighten the weight of the pump
D.They increase the strength of the shaft
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A.superheated
B.saturated
C.condensed
D.convected
A.radially from the shaft
B.parallel to each other and to the shaft
C.parallel to each other but at a right angle to the shaft
D.at an angle to each other and to the shaft
A.3 or 5
B.5 or 7
C.7 or 9
D.9 or 11
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
最新試題
The usual symptoms of cavitation in a centrifugal pump is （）.
The control mode in which the final control element is moved from one of two flexed positions to the other is known as （）.
Heavy wear in a particular area of the inner circumference of a packing ring may be caused by （）.
A salinity indicator is used to determine the （）.
Which of the listed pumps is NOT a positive displacement pump?（）
Who is responsible for ensuring that someone is assigned to close the watertight doors in an emergency?（）
A grease gun is generally used to lubricate a （）.
The rate of heat transfer between the hot and cold fluids passing through a shell-and-tube type heat exchanger will （）.
The rate of heat transfer from a hot region to a cold region is affected most by the （）.
Thermostatic expansion valves can be adjusted for （）.