pumps, valves and fittings

Have you tried google?
Have you tried the sites of pump, valve and fitting vendors?

"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?

What type of pump are you having problems with?

What is your problem?

Sounds like no Google connection.

Have you tried ???
It has a lot of information.

If you are looking for comprehensive information / explanations / definitions etc. ref. pump performance curves (Head - Flow, Efficiency, BHP, NPSH etc.) this is not all that easy to find.
Careful with calculations involving Affinity Laws (pumps at diff. speeds, reduction of impeller dia. etc.), useful but you need to be aware of what they really mean (e.g. Q, Speed -rpm-, Power not independent variables. Affinity Laws are simply eqn.s of Iso-efficiency curves. Understanding that, they are useful for many calcs.).

Regards,

mrs
(ps: e-mail: manuel-suarez@cantv.net)