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單項選擇題

With respect to centrifugal pump impellers, which of the following descriptions represents the correct centrifugal pump classification? （）

A.Single stage or multistage
B.High pressure or low pressure
C.Open or close coupled
D.Horizontal or vertical

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單項選擇題

If a radial piston hydraulic pump fails to deliver rated fluid volume, the cause can be （）.

A.contaminated fluid
B.pitted thrust rings
C.worn pintle bearings
D.obstructed suctions passage

單項選擇題

To maintain design discharge pressure from a centrifugal pump, the design clearance must be maintained between the （）.

A.shaft and impeller
B.motor and pump shaft
C.casing and impeller wearing rings
D.lantern ring and impeller