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A centrifugal pump may fail to deliver water when first started if the ______.
A.water seal pipe is plugged
B.pump is not primed
C.seal ring is properly located
D.impeller is flooded
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单选题A centrifugal pump may fail to deliver water when first started if the （）.A
water seal pipe is pluggedB
pump is not primedC
seal ring is improperly locatedD
impeller is flooded
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单选题A centrifugal pump can’t supply water after startingYou should check （）.A
priming waterB
power supplyC
packing glandD
bearing lubrication
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