更多"High-speed rotating in a centrifuga"的相关试题:
[单项选择]High-speed rotation in a centrifugal purifier can produce a force （） the force of gravity.
A. many thousand times larger than
B. the same as
C. many thousand times smaller
D. none of the above
[单项选择]If the bowl of a disk type centrifugal purifier when operated as a separator is not primed, the（）
A. oil has a tendency to emulsify in the bowl
B. purifier will act as a clarifier at the discharge ring
C. oil will be lost through the water discharge ports
D. oil solids will be deposited only at the intermediate top disk
[单项选择]A centrifugal fuel oil purifier should be shut down if （）
A. more sealing water is needed
B. the cover clamp needs tightening
C. the purifier has a bad vibration when started
D. water is discharged from the overflow line
[单项选择]A multistage centrifugal pump can be BEST described as having （）.
A. two or more impellers housed together in one casing and mounted on a single shaft
B. a single stepped impeller mounted in a progressively staged casing
C. a large radial clearance between the impeller and casing to prevent overheating due to
D. an increase in the discharge velocity of the liquid with a corresponding decrease in pressure through the stages
[单项选择]The capacity of a centrifugal pump can be increased by the installation of a larger diameter impeller Another means of increasing the pump capacity is to （）.
A. increase speed
B. increase the size of the cardent assembly
C. reduce wearing ring clearances
D. change the pump to a "close coupled" arrangement
[单项选择]Centrifugal pumps can be designed with a number of impellers （） to attain a high final delivery pressure.
A. in series
B. in parallel
C. either A or B
D. None of the above is tree
[单项选择]Shaft sealing in a centrifugal pump can be effected by （）.
A. the mechanical seal
B. packed stuffing boxes
C. either A or B
D. neither A nor B
[单项选择]A centrifugal pump can’t supply water after startingYou should check （）.
A. priming water
B. power supply
C. packing gland
D. bearing lubrication
[单项选择]Centrifugal pumps, however, can be designed with a number of impellers （） to attain a large amount of liquid.
A. in series
B. in parallel
C. assembled
D. together
[单项选择]Which of the following centrifugal pump components converts the liquid kinetic energy of velocity to the potential energy of pressure?（）
A. Impeller
B. Electric motor
C. Volute
D. Eye
[单项选择]A centrifugal pump vibrates excessively during operationUpon disassembling the pump it is found that the impeller is out of balanceWithout an available spare, you should （）.
A. drill holes through the heavy side of the impeller until it balances
B. weld counterweights to the light side of the impeller
C. remove metal from the heavy side by machining in a lathe
D. acid wash and serape the heavy side until it balances
[单项选择]Why are removable sleeves installed on centrifugal pump shafts?（）
A. They make it easier to replace the pump shaft packing
B. They can be economically replaced as they wear out
C. They can be removed when it is necessary to lighten the weight of the pump
D. They increase the strength of the shaft
[单项选择]The centrifugal pump component responsible for converting the mechanical energy of the liquid being pumped, to that of kinetic energy is the （）.
A. electric motor
B. volute
C. impeller
D. diffusion nozzle
[单项选择]A centrifugal pump produces the required pressure energy by means of a rotating （） provided with vanes.
A. propeller
B. impeller
C. circumference
D. screw
[单项选择]A centrifugal pump attempting to develop flow against a closed discharge valve has a/an （）.
A. capacity of 0%
B. efficiency of 100%
C. internal slippage of 0%
D. shut off horsepower rating of 100%
[单项选择]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
[单项选择]If a centrifugal bilge pump were continually operated with the discharge valve closed the （）.
A. motor overload would open
B. relief valve would open
C. pump would eventually overheat
D. motor would overheat
[单项选择]If a centrifugal pump were continually operated with the discharge valve closed, the （）.
A. motor controller overload would open
B. pump would eventually overheat
C. relief valve would continuously cycle open
D. motor would overheat
[单项选择]A double suction centrifugal pump impeller has been installed in the reverse direction, and will （）.
A. have a greater head capacity
B. operate with increased impeller efficiency
C. discharge through the suction side of the pump casing
D. require more power to run the shaft
