Auto Cycle valve

[6sunset6]

Anyone have experience with this valve? I have it , in process of installing.
Question about psi settings. Valve is rated for 3000 psi max. It comes from the factory with relief set at 2000. Detent 1 set at 1500 and detent 2 set at 1700.
Detent 2 must be 200 psi above detent 1 and 300psi under relief.
The instructions say the detents should not be set higher than 2000 psi. That means the relief cannot be set higher than 2300 psi.
Sort of a waste of 700 psi . Anybody have this valve and fool around with the settings? Oh yeah cylinder is rated for 3000 psi.

 

[oldnslo]

Anyone have experience with this valve? I have it , in process of installing.
Question about psi settings. Valve is rated for 3000 psi max. It comes from the factory with relief set at 2000. Detent 1 set at 1500 and detent 2 set at 1700.
Detent 2 must be 200 psi above detent 1 and 300psi under relief.
The instructions say the detents should not be set higher than 2000 psi. That means the relief cannot be set higher than 2300 psi.
Sort of a waste of 700 psi . Anybody have this valve and fool around with the settings? Oh yeah cylinder is rated for 3000 psi.

Never seen or used one but reading through the instructions it makes me wonder if you can adjust the detents to the point they won't release fully?

I would suspect that if you get a tough piece of wood you can manually hold the valve to keep extending the cylinder.

Agree, the numbers don't make much sense.

Roy

 

[RandyT]

My Iron and Oak splitter uses that exact valve. You can hold the number 1 valve to aid splitting really hard wood. Operates upto the relief pressure. I have had to increase the detent pressure on the return valve to eliminate the dual lever kickout when the oil was cold. don't have a pressure gauge so I don't know what the exact pressure is but my splitter is a 30 ton with a 5 inch cylinder and to achieve that rating would have to be operating at 3000 psi.

 

[J_J]

That is not the way to figure the tonnage on the cyl.

A 5 in cyl, and 2 in shaft, with a pressure of 3000 lbs will have a force of 58,905 lbs or 29.45 ton.

So if the relief is not set at 3000 psi you can not develop the tonnage.

For instance, if it is 2500 psi = 49,087, or 24.5 ton

 

[wdchyd]

One thing to consider with these valves is the higher your pressure detents are the more wear and tear your components will see during each cycle.....reducing the life expentancy of the cyl seals and potentially the pump if the pressure is set too high......:confused2:

You can set these lower for most of your splitting then hold the lever when a larger log won't split with autocycle....

best to install a guage to tune the performance of the detents while using in the field.....

 

[tawilson]

I put one on my homemade splitter years ago and my experience with it echoes RandyT's, even down to never putting a gauge on it.

 

[J_J]

Why would you never put a gage on the log splitter valve especially if the relief comes set for 2000 psi and your hyd pump is capable of 3000 psi.

If I remember right, the relief can be set up to 3000 psi or set to 100 psi below pumps psi, or set same as the tractor psi.

On a 4 in cyl and 2 in shaft, 1000 psi is a difference of 12,586 lbs, or about 6 ton.

Leaving the valve set to 2000 psi is not even logical, and adjusting the relief with out a gage is not logical.

 

[wdchyd]

Funny, true story........in the seventies when I was working for a hyd repair shop, the lead mechanic and engineer together just finished making a custom built log splitter (for the engineers brother)......

During the first start-up, they tee'd in a hyd guage in on the pressure line and put a chunk of steel between the 4 foot cyl and wedge........they ran it up to pressure watching the guage and didn't notice they bent the I-beam on the first run......:confused2:

We got a good chuckle out of it...They didn't though......:laughing:

 

[RandyT]

One thing to consider with these valves is the higher your pressure detents are the more wear and tear your components will see during each cycle.....reducing the life expentancy of the cyl seals and potentially the pump if the pressure is set too high......:confused2:

You can set these lower for most of your splitting then hold the lever when a larger log won't split with autocycle....

best to install a guage to tune the performance of the detents while using in the field.....

I can attest to the wear and tear. the cylinder cap has unscrewed three times in 7 years and 50 hours. tearing the cap seal each time. The third rebuild a set screw was installed to prevent the cap from unscrewing by the hydraulic place.

 

[SSdoxie]

The pressure settings mentioned (1500, 1700, & 2000) are for testing valve for correct operation after first plumbed in. Then pressure can be set to desired settings provided: main does not exceed 3000 psi, detent #2 is at least 300 psi lower than main relief or any relief upstream in pump supply,but not more that 2000 psi, and detent #1 must be 200 psi lower than Detent #2.

 

[6sunset6]

ok I got the 2300 max on the main relief, 2000 on detent 2 and 1800 on detent 1. I am leaving 700psi on the table but that's the way it is. If I need more pressure i.e. 3000 on the cylinder I will call Prince.
I have a gage in the main pressure supply line. How does one go about setting all the pressures including the pump? With out damaging anything.

Also I have a set of valves downstream on the power beyond port from this set
I assume it's relief can be set lower than the relief on the first valve, maybe 2000 ?

 

[J_J]

Why don't you want to set your valve relief to 50 psi below the pump pressure.

As I said before, you lose a lot of force by not setting the valve relief, 50 psi below the pump pressure.

If your log splitter relief is set to 2300 psi, you limit any valve downstream to 2300 psi. If this is a 3pt log splitter, the limit you set on the log splitter valve will limit the pressure downstream , and if the flow from your log splitter goes back to the 3pt, that will limit the force on the 3pt.

Is this valve on a 3pt log splitter or a standalone?

Difference in force if you use 2300 psi instead of 3000 psi.

4 in cyl 2 in rod

2300 psi = 28,903 lbs
3000 psi = 37,699 lbs

 

[6sunset6]

Why don't you want to set your valve relief to 50 psi below the pump pressure.

As I said before, you lose a lot of force by not setting the valve relief, 50 psi below the pump pressure.

If your log splitter relief is set to 2300 psi, you limit any valve downstream to 2300 psi. If this is a 3pt log splitter, the limit you set on the log splitter valve will limit the pressure downstream , and if the flow from your log splitter goes back to the 3pt, that will limit the force on the 3pt.


On a 4 in cyl and 2 in shaft, 1000 psi is a difference of 12,586 lbs, or about 6 ton.

Is this valve on a 3pt log splitter or a standalone?

JJ The whole story is here.
http://www.tractorbynet.com/forums/build-yourself/226024-woodsplitter-build-2-a.html

 

[J_J]

I saw all that but did not connect the two threads.

My point here is if the pump can develop 3000 psi, and if you want max power out of the log splitter, you would set the Autovalve to 50 psi below 3000 psi.

That is so you can call you splitter a 18.53 ton, verses a 14.45 ton splitter , using a 4 in cyl, and 2 in rod.

 

[glastron23]

6sun. the first thing about these auto cycler valves to remember is that once you pull the handles it will stroke full out and then full retract. the pressure settings on the detents is what causes the piston to reverse the stroke out/in. the higher the pressures on the detents the more resistance it will take to achieve this. the more strain you put on the engine/pump/hoses/cylinder and the more heat you will develop.
That you need to do is set the detents to the type of wood you mainly split, soft wood needs very little pressure to split,500 to 750 psi. maple is the same. birch, beech, oak, needs more but twisted yellow birch will really try the machine.
I would leave the main pump pressure at 3000psi, then play with the detents for the wood you mainly use. If a few pieces require more then just grab the handle and do it manually. This will prevent the system from working at max psi all the time when it's not required. Jim

 

[6sunset6]

I see. Full pump pressure never develops then until the valve handle is held manually. The system will reverse mid stroke if it hits something hard. Then hold it manually. As long as it does not do it all the time it's ok. But if it does that crank up the detent setting.
I have to go take some pictures.

 

[6sunset6]

Question I ordered the Prince valve
Surplus Center - 1/2" NPT 20 GPM 1500-3000 PSI RELIEF VALVE RV-H4
It says it is an inline valve which is nice and would save some fittings. But the space I have to work in will not allow it to be plumbed in line. Bummer. But I see no reason that I cannot hang it on a tee, one pressure port piped to the tee and the other a gage port. Tank port goes into the return line. Another question I assume "tank" means a return line and does not have to be direct to the tank. I would prefer to have all returning oil go through the filter, which is in the return line.

 

[J_J]

Yes, tank line is the return fluid from all the cyl, motors, anything that uses the fluid to produce force. Since the return flow is low pressure, you can combine all of the return flows into one hose going to the filter and then the reservoir/tank, as long as the back pressure stays low.

You can have one hose going to the filter if the flow rate is matched with the filter capability. The filter should have an indicator, either a gage, or a electronic warning device like a light or horn to warn of filter changes.