Flow Control Valve

[JohnDeereJoey]

I am looking at upgrading my PTO power pack and wish to run implements with different flow rate requirements...from about 16 GPM to 20 GPM. (All of them can handle 3000 PSI maximum...one of them NEEDS a minimum of 3000 PSI.)

So...if I get a pump (hydraulic power pack) capable of say 20 or 25 GPM at 3000 PSI, is it a simple matter of adding a flow control valve to reduce flow to 16 GPM but maintain 3000 PSI if the load demands it. I looking a Prince RD100 valve. Link at end of this post.

Are there any pitfalls with this approach?

Joel

LINK:

Prince Manufacturing Corporation > Products > Hydraulic Valves > Flow Control > Model RD100

 

[oldnslo]

That flow control will work but will create a little heat since flow controls require some pressure drop to operate.

another option if you have the PTO power is idle the tractor down for lower flows

 

[JohnDeereJoey]

Thank you for your post oldnslo.

I should be with the added heat...the reduced flow is mainly needed in the winter, and any the new power pack will have a cooler.

Reduced pto rpm has worked really well to decrease flow to the snow blower. I'm wondering if full pto speed with a flow control valve would allow full pressure when the blower is under heavy load?

 

[oldnslo]

Flow should not have any effect on pressure so the flow control should have very limited effect on how the blower works under load.

 

[Midniteoyl]

I'm wondering if full pto speed with a flow control valve would allow full pressure when the blower is under heavy load?

Your pressure should be the same or real close from idle to full RPM. Flow increases with RPM, not pressure.

 

[Dave M7040]

I am looking at upgrading my PTO power pack and wish to run implements with different flow rate requirements...from about 16 GPM to 20 GPM. (All of them can handle 3000 PSI maximum...one of them NEEDS a minimum of 3000 PSI.)

So...if I get a pump (hydraulic power pack) capable of say 20 or 25 GPM at 3000 PSI, is it a simple matter of adding a flow control valve to reduce flow to 16 GPM but maintain 3000 PSI if the load demands it. I looking a Prince RD100 valve. Link at end of this post.

Are there any pitfalls with this approach?

Joel

LINK:

Prince Manufacturing Corporation > Products > Hydraulic Valves > Flow Control > Model RD100

A caution would be to make certain you have the pto power needed for the new power pack.

Landpride's unit needs 52 pto hp to produce 25 gpm at 3,000 psi.





While that seems to be right at the limit of your tractor's pto

ability, you wont have any power left for moving the tractor.

Dave M7040

 

[JohnDeereJoey]

Thank you for the replies folks. Greatly appreciated.

For my tractor and implements, a 20 GPM/3000 PSI 3-point-hitch power pack would work well. Does anyone know of a driveshaft (as opposed to the pump directly mounted onto the tractor's PTO) unit available? (The only one I found is John Deere and it's they apparently are not taking orders for it.)

The LandPride HRS30 looks really nice, but as pointed out a 25 GPM/3000PSI pump is at the very maximum of my tractor's available PTO power. Which leads me to a $64,000 question...if an power pack like the HRS30 was used with a flow control valve set to 20 GPM, would the load on the PTO drop accordingly?

Joel

 

[oldnslo]

Joel
Presuming that power pack has fixed displacement gear pump the flow control will not reduce HP required since all of the flow will be at what ever pressure the system requires

 

[JohnDeereJoey]

Joel
Presuming that power pack has fixed displacement gear pump the flow control will not reduce HP required since all of the flow will be at what ever pressure the system requires

I must admit I thought otherwise...but the more I think about what you said the more I think you are correct. There would be less power to the implement, but the load on the PTO would stay essentially constant. If true, it sounds like all I would be doing is generating heat!

 

[oldnslo]

Joel
Yes The highest load will dictate pressure at the pump or flow control inlet any excess oil being returned to tank will be energy loss or heat. Usually not a big issue on system that requires momentary flow like cylinder operating but when continuous duty like running a motor the heat generated can be a concern.