NPSH -

[dbday]

Hi,

Can anyone tell me if there is a general rule of thumb to work out a typical NPSH requirement for a 3 or a 5 plunger pump.
I can quite happily work out the acceleration head for the lines I have, so what want to do is to make sure I am getting this in the normal range for such pumps before I talk to the pump manufacturers themselves.

Thanks for any help

 

[BigInch]

As the number of plungers increase the fluid draw approaches a more constant flowrate and accelerations associated with each plunger overlap to make the flow draw nearly constant in the supply pipe. The acceleration head requirement drops significantly after 3 and chances are head requirements will be minimal if you need any additional head all.

What would you be doing, if you knew that you could not fail?

 

[JJPellin]

If you search for threads involving reciprocating pumps, you will find a number that are relevant to your question. This is one that I recalled:

"Liquid Separation From Plunger In Reciprocating Pump (Water)"

I am having some trouble linking to this post. You can easily find it with a search.

Johnny Pellin

 

[stanier]

Suggest you invest in the book by Miller as this is the classic for reciprocating pumps.
books.google.com › Technology & Engineering › Hydraulics

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