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單項選擇題

Air leakage between the shaft and stuffing box packing in a centrifugal pump is prevented by （）.

A.a compressed packing gland
B.lantern tings between the packing rings
C.a liquid seal
D.the stuffing box gland

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單項選擇題

Tube leaks in the distillate cooler of a two stage flash evaporator will result in （）.

A.loss of second stage vacuum
B.contamination of the distillate
C.lower feed inlet temperature
D.contamination of the second stage condenser

單項選擇題

The pressure of a liquid leaving the pump can be referred to as the （）.

A.total head
B.discharge head
C.net positive suction head
D.suction head

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