更多"The discharge rate or capacity of a"的相关试题:
[单项选择]When starting a centrifugal pump, the discharge valve should be （）.
A. closed
B. opened fully
C. cracked open
D. partly open
[单项选择]The combined fan discharge rate in an inert gas system is related to the（）.
A. shoreside loading rate
B. maximum cargo pump discharge rate
C. boiler forced draft fan rate
D. size of the largest cargo tank
[单项选择]The discharge head of a centrifugal pump will vary directly with the （）.
A. change in impeller diameter
B. square of the impeller diameter
C. cube of the impeller diameter
D. impeller efficiency for large changes in the size of the impeller
[单项选择]If you heard a ‘crackling’ noise in centrifugal pump, the most probable cause of the problem would be（）
A. insufficient speed
B. cavitation
C. excess discharge pressure
D. excessive net positive suction head B
[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]If the capacity of a centrifugal pump decreases gradually over a long period of time, you should replace the （）.
A. packing gland
B. mechanical seals
C. lantern rings
D. wearing rings
[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
[单项选择]A spring-loaded centrifugal flyweight governor responds to reduced engine load with an immediate increase in （）
A. pilot valve oil pressure
B. speeder spring force
C. compensation needle valve clearance
D. centrifugal force on the flyweights
[单项选择]What is a characteristic of all centrifugal cargo pumps? （）
A. They are self-priming
B. Decreasing the speed of rotation will decrease the discharge pressure
C. Opening the discharge valve wider will increase the discharge pressure
D. All of the above
[单项选择]For optimum results, centrifugal purification of heavy fuel oil should be accomplished with the fuel at the lowest practicable（）
A. throughput
B. additive percent
C. cetane number
D. TBN number
