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HP in and out of Pump

HP in and out of Pump

HP in and out of Pump


I've been working on a design using hydraulics and I wanted to sanity check myself.  The pump I'm looking at puts out 11GPM at 4250 PSI and requires an input HP of 11HP.

By my calculations I'll be getting out of the pump 27HP.  Does this make sense?  More HP out then going in?  Also, from this pump it looks like I can drive 2 23HP drive motors (10 GPM, 2000PSI).

-Lucas Goodwin

RE: HP in and out of Pump

Sorry, 2 11HP drive motors.  Was thinking of a 20GPM drive motor I was also looking at.


RE: HP in and out of Pump


You are sane.

The pump would use 11 HP at 1,600 PSI. At 4250 it would require the 27 HP you figured.

A pump that is rated at a given pressure can be run at that pressure and have a reasonable life. It can be run at lower pressures and will be more efficient and have longer life in most cases.

The other thing is at what RPM is the 11 GPM flow produced. Slowing the pump down reduces its maximum output and allows it to opearte at a higher pressure with the same motor. Reducing RPM will also make it less efficient
so there needs to be a happy medium.

If the pump is rated at 11 GPM at 1,800 RPM it will only produce 7.26 GPM at 1,200 RPM. Then it can go up to 2,500 PSI with the 11 HP motor.

Bud Trinkel CFPE
fluidpower1 @ hotmail.com

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