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單項選擇題

An increase in rotor clearances in a rotary pump will （）.

A.increase discharge pressure
B.decrease pump capacity
C.decrease pump cavitation
D.decrease reaction ring clearance

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單項選擇題

Sweating of the refrigeration system compressor crankcase is caused by （）.

A.too much superheat
B.insufficient superheat
C.suction pressure too low
D.excessive refrigerant returning to the compressor

單項選擇題

Which bearing will carry the load on two small points diametrically opposite to each other?（）

A.Needle
B.Tapered roller
C.Roller
D.Ball

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