Noticeable difference 2000psi vs 2250psi

[bdoyle]

I am looking at pto gear pumps and the backhoe I have requires 7 GPM @ 2320 psi. Most pumps I find are rated at 2000 psi but I have seen one Chief pump @ 2250. Would I notice the difference or is it a matter of tweaking the operating RPM a bit. I don't believe the have a internal pressure relief valve or do they?
thanks!
Brian

 

[J_J]

If you have a 3 in cyl bore and 1.5 in shaft, and 2000 psi, the force would be about 14,137 lbs.

------------------------------------------------------2320 psi, -----------------------------16399 lbs

If your BH has a relief, set it same as tractor relief.

Rpm's only control the volume in GPM's.

The hyd component develops the pressure.

 

[Egon]

If it's a PD pump the RPM will dictate the flow rate. The top pressure will be regulated by the PSV.

The top pressure can be reached at any flow rate with lower rates taking more time to fill the hydraulic system.

When using my no. 7 backhoe I usually throttle way back so everything is moving slower. Makes it easier for ham handed old folk to react.

 

[bdoyle]

So when they say that the pump will deliver 7 GPM @ 2000 PSI it is more of a comparative tool than a limitation. I have to add a pressure relief valve when I plumb in pump and tank. Just want to make sure I do this once, correctly. I think I may just use tractor hydraulics just to test every thing out before laying out the cash on pumps ect.
Thanks,
Brian