你可能感興趣的試題

One of the main functions of wearing rings, as used in a centrifugal pump, is to （）.

A.maintain radial alignment between the pump impeller and casing
B.absorb all impeller shaft end thrust
C.prevent water leakage to the atmosphere
D.prevent wear of the pump casing and/or impeller

單項選擇題

Brine density in a distilling plant is measured with a/an （）.

A.psychrometer
B.salinometer
C.anemometer
D.sphygmomanometer

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For safe storage, the maximum allowable temperature to which refrigerant bottles should be exposed is （）.

你可能感興趣的試題

One of the main functions of wearing rings, as used in a centrifugal pump, is to （）.

Brine density in a distilling plant is measured with a/an （）.