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單項(xiàng)選擇題

If you were operating a centrifugal water service pump with worn wearing rings, the （）.

A.pump would be very noisy
B.pump would vibrate excessively
C.pump would develop insufficient flow
D.stuffing box would leak excessively

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單項(xiàng)選擇題

The packing installed in the pump stuffing box is lubricated by （）.

A.gravity and feed oil cups
B.grease cups
C.hand during installation
D.leakage through the stuffing box

單項(xiàng)選擇題

The steam coils in a high pressure evaporator used for saltwater service should be de-scaled with （）.

A.a needle gun
B.soap and water
C.a wire brush
D.a chipping hammer

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