A.kg
B.MPa
C.mH20
D.None of the above
您可能感興趣的試卷
你可能感興趣的試題
Which of the following are components of a mechanical seal? （）
(1) stationary ring
(2) rotational ring
(3) packing
(4)spring
A.(1), (2) and (3)
B.(1), (2) and (4)
C.(2), (3) and (4)
D.None of the above
A.variable stroke pumps
B.multistage pumps
C.positive displacement pumps
D.triple-ported pumps
A.mixed-flow pump
B.axial-flow pump
C.centrifugal pump
D.displacement pump
A.on top cover
B.on sides of bowl
C.in drain line on the discs
D.on the discs
A.oil
B.sea water
C.refrigerant
D.fresh water
最新試題
Which of the problems listed would came the discharge temperature of an R-12 refrigeration compressor to increase?（）
The rate of heat transfer between the hot and cold fluids passing through a shell-and-tube type heat exchanger will （）.
If the thermal bulb of an expansion valve is incorrectly placed at the center of the coil instead of the end, it will （）.
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 head pressure of a reciprocating refrigeration compressor is excessive, （）.
Heavy wear in a particular area of the inner circumference of a packing ring may be caused by （）.
A grease gun is generally used to lubricate a （）.
The amount of fluid friction or internal friction inherent in a mineral lubricating oil is reflected as a measure of its （）.
A salinity indicator is used to determine the （）.
A gradual decrease in the discharge pressure of an operating hydraulic pump can be caused by （）.