Pump sizing question - several pump inlets w/ common header 1

[Remisero]

Dear Forum,

I would appreciate any feedback you might have, or if you could point me to a good book on pumps in order to resolve a question I have relating to pumps connected to common header inlet (4" drain line from 300,000 gallon water tank):

My question is if there is any practical formula or rule of thumb on how to determine if a new pump I want to install (3" inlet 240GPM @ 12ft.) will starve in any way two already installed pumps: (2.5" inlet 70GPM @ 65ft.) and (3" inlet 115GPM @ 75ft.) when they all operate at the same time.

I still haven’t found any literature on this, so I would appreciate any input you might have. This new pump I want to install is to fill up tank trucks with water.

 

[NickiConway]

I would suggest you determine the NPSHa (Net Positive Suction Head Aviavble) with all three pumps running and compare to the NPSHr (Net Positive Suction Head Required) for each individual pump. As for a good book, I'm not sure off hand, but I think a quick “Google” of NPSH will give you most of the basics.

Nic