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单选题Pitting in the suction areas of a centrifugal pump bronze impeller is usually caused by （）.A cavitationB electrolysisC abrasionD corrosion

题目
单选题
Pitting in the suction areas of a centrifugal pump bronze impeller is usually caused by （）.
A

cavitation

B

electrolysis

C

abrasion

D

corrosion

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相似问题和答案

第1题：

All of the following steps are taken in starting a centrifugal pump，EXCEPT to ______．

A.Set the relief valve

B.Check the lubrication system

C.Vent the pump casing

D.Open the pump suction and discharge valves


正确答案：A

第2题：

单选题
With respect to centrifugal pump impellers, which of the following descriptions represents the correct centrifugal pump classification? （）
A

Single stage or multistage

B

High pressure or low pressure

C

Open or close coupled

D

Horizontal or vertical


正确答案： C
解析： 暂无解析

第3题：

If a centrifugal pump is driven by a constant speed electric motor and produces a discharge pressure less than designed, the cause is probably ______.

A.excessive pump speed

B.excessive suction head

C.worn wearing rings

D.gross pump misalignment


正确答案：C

第4题：

单选题
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


正确答案： A
解析： 暂无解析

第5题：

单选题
What is a function of the wearing rings used in most centrifugal pumps?（）
A

Absorb erosion of high velocity discharge stream

B

Seal pump shaft against entry of air

C

Isolate the discharge side from the suction side

D

Dampen the turbulent discharge flow


正确答案： C
解析： 暂无解析

第6题：

You start a centrifugal cargo pump to discharge cargo．The pump works for a while and then loses suction．This could be caused by ______．

A.The pump running backwards

B.Incomplete priming

C.The discharge head being too high

D.All of the above


正确答案：B

第7题：

单选题
Which of the following statements is correct with regards to the operation of a centrifugal cargo pump?（）
A

Oil is discharged from the impeller through the outlet

B

Gravity causes the oil to flow toward the discharge

C

The self-priming feature of the centrifugal pump enables it to draw its own suction as it starts

D

The discharge capacity varies directly with the speed of the impeller


正确答案： C
解析： 暂无解析

第8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


正确答案：C

第9题：

单选题
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


正确答案： A
解析： 暂无解析

第10题：

单选题
A centrifugal bilge pump requires priming （）.
A

primarily to lubricate the shaft seals

B

due to the inability of this type of pump to lift water to cover the suction (eye) of the impeller

C

to initially unload the pump by having its head pressure equal to discharge pressure

D

in order to overcome the potential energy of water in the discharge line


正确答案： D
解析： 暂无解析

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