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单选题
A centrifugal pump produces the required pressure energy by means of a rotating （） provided with vanes.
A
propeller
B
impeller
C
circumference
D
screw
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单选题A centrifugal bilge pump requires priming （）.A
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one size larger than the pump discharge nozzleB
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单选题A pump is defined as device that（）A
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imparts energy to a fluid to move it from level ‘A’ to level ‘B’C
creates a vacuum to move a liquid in all installationD
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enable a visual inspection of the pump while it is runningC
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单选题Which of the listed statements is correct concerning the starting of centrifugal pumps?（）A
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单选题The basic function of the centrifugal pump impeller is to （）.A
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directly increase the velocity of the liquid being pumpedC
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单选题To maintain design discharge pressure from a centrifugal pump, the design clearance must be maintained between the （）.A
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centrifugal pump is cheaper than reciprocating pumpB
the size of centrifugal pump with same capacity is smaller than that of reciprocating pumpC
centrifugal pump makes maintenance easier than reciprocating pump doesD
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单选题Some of the energy fed into the pump will be dissipated as （） due to mechanical inefficiencies, the remainder will be converted into pressure rise and fluid velocity.A
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单选题The amount of fluid delivered by a centrifugal pump can be regulated by （）.A
throttling the pressure lineB
changing the speed of the rotorC
either A or BD
None of the above is tree
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单选题Which of the following centrifugal pump components converts the liquid kinetic energy of velocity to the potential energy of pressure?（）A
ImpellerB
Electric motorC
VoluteD
Eye
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