Why does a TPH log splitter have a pressure relief valve?

[Dead Horse]

My American TPH splitter has a pessure relief valve. Since tractors all have their own PRV in the hydraulic circuit, why does this splitter's cylinder control have a PRV?

Set properly, is it designed to "kick off" the retract cycle detent?

 

[Treemonkey1000]

My guess is that it would be like a Safety valve if the Tractor hydraulics were to fail and over pressure the log splitter. Or if the Hydraulics from the tractor were a bit on the high side pressure wise for the splitter.

 

[brandoro]

I agree that it is to protect the splitter regardless of the pressure supplied. They don't know which tractor(s) you might connect the splitter to so they build a limit into it to protect the splitter, and the operator, from damage from excess pressure.

 

[Mechanos]

My American TPH splitter has a pessure relief valve. Since tractors all have their own PRV in the hydraulic circuit, why does this splitter's cylinder control have a PRV?

Set properly, is it designed to "kick off" the retract cycle detent?

It's probably there just for that reason..... to "kick off" the retract cylce detent. I find this feature very convenient and quite a time saver. Instead of standing there doing nothing while retracting the ram, I just click it into the retract detent and go about my business picking up the split wood and/or picking up the next log to place in the splitter. When the ram fully retracts, it kicks the control lever back into the neutral position and it's sitting there waiting for me to split the next log.

 

[mmurphy]

Not all tractors are set for the same pressure.
The log splitter is probably set where manufacturer says everything will hold with out flying apart.
If log spliiter safely bypasses pressure at 2000 psi, but tractor is at 2500 psi, the tractor relief setting will not have helped on a tough overload.

 

[J_J]

Dead Horse

If you are trying to increase the force on the splitter, and the relief is set below the tractor hyd relief, you can adjust the log splitter relief to match the tractor relief setting if the log splitter can take the tractor hyd pressure. Leave the detent pressure where it is.

 

[Dead Horse]

Dead Horse

If you are trying to increase the force on the splitter, and the relief is set below the tractor hyd relief, you can adjust the log splitter relief to match the tractor relief setting if the log splitter can take the tractor hyd pressure. Leave the detent pressure where it is.

JJ

The "detent pressure" I am not sure of. The retract cycle is in a detent position, but it does not kick out at the end of the cycle. I looked the splitter up on the internet and could not find any information about this particulat model, (American) other than the basic statistics.

There is only one adjustable pressure valve on the splitter. (It is a 30" throw, 4 inch cylinder) I am running it on my Kubota 3710. The tractor hydraulics are not hitting their relief valve limit on a really tough log, so I figure I can dial up the relief valve on the splitter until that limit.

I cannot find the hydraulic pressure capacity for the L3710, but the American specification say the splitter can take 2500#. I would think the tractor is less than that........as the loader cylinders are half the diameter of the one on the splitter. What do you think?

BTW, to increase pressure setting you turn the needle valve "in", correct?

 

[J_J]

Here is a Prince log splitter valve, showing the relief valve and the detent relief valve.
Page 3. It may have a non adjustable relief detent.

Use a 3000 psi hyd gage.

To adjust valve relief, turn screw in to increase pressure. Most relief setting are set using 12 GPM hyd flow. Adjust splitter relief to equal the tractor relief, or 50 psi lower.

You say it doesn't kick out, then something is wrong. Is this a factory valve or did someone replace it with something else. Might have to disassemble the valve, inspect and clean it.

http://www.princehyd.com/Portals/0/products/valves/catalog/ValvesLsRd25.pdf

Standard relief on Prince valves is 2250 psi but will go up to 2750 psi.

 

[Dead Horse]

I bought it used, though I don't think it had many hours on it. The pressure relief valve looks like it has been wrenched on, paint is missing. The guy I bought it from is a nincompoop, so he could have backed the valve off. It is a great, powerful splitter with a 4 way wedge and i have split a LOT of wood with it The detent relief has never worked.

I am gonna a dial it down to the point the tractor's EPR kicks in and then back it off a tad. Maybe that will fix the detent issue. I may not be getting enough pressure to kick off the detent, though at full retract, the tractor's hyd pump does labor a bit.

I just as soon not pull the valve apart if I don't have to.

Thanks for your help, JJ! Thanks a lot.

Did this load just last week.

 

[J_J]

Those log splitter valves are only about $60 from

https://www.surpluscenter.com/item.asp?item=9-7724&catname=hydraulic

The auto valves are even better, but pricey.