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NPSHA Evaluation

07/13/2009 3:16 AM

what does NPSHA mean and how can you evaluate it for a reciprocating pump?
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PWSlack
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#1

Re: NPSHA evaluation

07/13/2009 3:23 AM

Net Positive Suction Head evaluates whether there is enough fluid at the inlet of a pump to prime it and to make sure that the pump doesn't cavitate, i.e. pull a vacuum on the incoming fluid, making it boil. Cavitation will wreck a pump in short order.

What sort of reciprocating pump? What size? What is the fluid? What is its temperature and pressure?

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Hendrik
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#2

Re: NPSHA evaluation

07/13/2009 3:29 AM

Net Positive Suction Head Available relies on atmospheric pressure and will change during a period. It is best calculated using the minimum value.

The pump side NPSHR (Required) will depend on the pump specs.

There must always be enough Available to Satisfy the Required.

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Codemaster
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#3

Re: NPSHA evaluation

07/13/2009 6:06 AM

Don't forget the acceleration head! You might need a pulsation damper on the suction pipe.

Codey

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