海船船员考试
单选题The basic function of the centrifugal pump impeller is to （）.A directly increase the pressure of the liquid being pumpedB directly increase the velocity of the liquid being pumpedC convert the potential energy of the liquid to kinetic energyD separate
题目
directly increase the pressure of the liquid being pumped
directly increase the velocity of the liquid being pumped
convert the potential energy of the liquid to kinetic energy
separate air from the liquid being pumped
相似问题和答案
第1题：
What is the function of wearing rings found on some centrifugal pumps ________．
A.Absorb erosion of high velocity discharge stream
B.Seal pump shaft against entry of air
C.Isolate the outlet side from the inlet side
D.Dampen the turbulent discharge flow
第2题：
Single stage or multistage
High pressure or low pressure
Open or close coupled
Horizontal or vertical
第3题：
It is possible to mount a double suction centrifugal pump impeller with the vanes facing in the wrong direction. This would cause the pump ______.
A.head capacity to improve
B.discharge to be reversed
C.efficiency to decrease
D.slippage to decrease
第4题：
have a greater head capacity
operate with increased impeller efficiency
discharge through the suction side of the pump casing
require more power to run the shaft
第5题：
Absorb erosion of high velocity discharge stream
Seal pump shaft against entry of air
Isolate the discharge side from the suction side
Dampen the turbulent discharge flow
第6题：
What causes cavitation in a centrifugal pump ________．
A.Vapor pockets in the flow stream
B.Rough impeller surfaces
C.Worn wearing rings
D.Heavy fluid in the flow stream
第7题：
Oil is discharged from the impeller through the outlet
Gravity causes the oil to flow toward the discharge
The self-priming feature of the centrifugal pump enables it to draw its own suction as it starts
The discharge capacity varies directly with the speed of the impeller
第8题：
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
第9题：
reduce radial thrust to the impeller
double the liquid velocity through the pump when compared to a single volute
reduce hydraulic end thrust
provide the effect of multi-staging
第10题：
two or more impellers housed together in one casing and mounted on a single shaft
a single stepped impeller mounted in a progressively staged casing
a large radial clearance between the impeller and casing to prevent overheating due to
an increase in the discharge velocity of the liquid with a corresponding decrease in pressure through the stages