Giving up on buying a splitter. I borrowed a Timberwolf TW-2 and fell in love, but not with the price tag. Figure I'm best to build a splitter the way I would like one. I intend to build a splitter with a 5"x24" cylinder and a 22 gpm pump backed by an 11 horse motor. However, I cannot find anything above 3000 psi in cylinder, pump, & valve. What are the 35+ ton splitters attaining their ratings with items only rated to 3000 psi? Also, from valve to tank (return) & tank to pump can be low pressure hoses right? I only see filters rated to 200psi.
Splitter Build.. Have some questions related to hydraulics.
- Thread starter SIERRADMAX
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Caseihmech
New Member
Hey there,
To calculate your tonnage you have to figure you surface area in square inches on your cylinder piston and multiply by 3000 psi to get your tonnage. The more gallons you put to the cylinder the faster your cycle times will be. That doesn't affect your splitting force. Flow is speed, pressure is force.
Your filter will be on the suction side of your pump it will be low pressure. The valve you need with a gear pump is a open center valve. So when you are not stroking the valve you will be sending oil back to sump with no restriction. So the return side of your valve will be low pressure. The only high pressure you will see is, pump to valve, valve to cylinder ends.
3000 PSI is the max the pump should be putting out because on your valve you will have a relief valve. Which should be adjustable, You will want that set at about 2800 PSI. (or lower, to protect the rod from bending) You don't want the pump to be hitting 3000 psi every time it hits a hard to split piece. The pump will not last very long at all. Depending on the valve you get, you can have a detent return. That should be set to kick out as soon as the cylinder retracts all the way. So again your pump is not going up to high pressure.
Have thought about a two stage pump. Good speed then slows down to split hard piece.
One last thing, When buying fittings go with JIC or O-ring face fittings. They will be more in price the pipe thread, but they will seal up much better and if you have to pull lines off they will come apart much easier.
It will be a fun project, and when you are done you will have what you want. They hydraulics on a wood splitter are a real basic system.
To calculate your tonnage you have to figure you surface area in square inches on your cylinder piston and multiply by 3000 psi to get your tonnage. The more gallons you put to the cylinder the faster your cycle times will be. That doesn't affect your splitting force. Flow is speed, pressure is force.
Your filter will be on the suction side of your pump it will be low pressure. The valve you need with a gear pump is a open center valve. So when you are not stroking the valve you will be sending oil back to sump with no restriction. So the return side of your valve will be low pressure. The only high pressure you will see is, pump to valve, valve to cylinder ends.
3000 PSI is the max the pump should be putting out because on your valve you will have a relief valve. Which should be adjustable, You will want that set at about 2800 PSI. (or lower, to protect the rod from bending) You don't want the pump to be hitting 3000 psi every time it hits a hard to split piece. The pump will not last very long at all. Depending on the valve you get, you can have a detent return. That should be set to kick out as soon as the cylinder retracts all the way. So again your pump is not going up to high pressure.
Have thought about a two stage pump. Good speed then slows down to split hard piece.
One last thing, When buying fittings go with JIC or O-ring face fittings. They will be more in price the pipe thread, but they will seal up much better and if you have to pull lines off they will come apart much easier.
It will be a fun project, and when you are done you will have what you want. They hydraulics on a wood splitter are a real basic system.
Ram 1500 with an axe...
Minister of Fire
I bought all my stuff for my last build here http://www.surpluscenter.com/hydraulic.asp?catname=hydraulic very good prices & you can buy your hoses premade with the ends you need.
2 stage pump is what I intend to use. I might mix/match between surpluscenter, northern tool, grainger, & mcmastercarr for parts. Any idea on an oil tank size? Judging by the dimensions of the PW-2, it has a 10 gallon tank. Oil lines got rather warm after a couple hours of use. I'm assuming the 5"x24" will require more oil. Will a 15 gallon suffice?
You will not need to exceed 10 Gal. Proper fitted hoses will make more difference in run temp than a larger tank will at that point.
Ignore the advertised tonnage of factory built splitters. Its a sales gimmick and almost NEVER will the tonnage rating be correct (there are a couple of companies that are honest).
Don't plan on building the hydraulics to obtain the 3000 psi relief pressure. You simply won't need that much pressure. I run a 5" ram also, and have the pressure set to 2750 psi. Unstoppable. You can only run up to the pressure of the lowest rated part. Components above 3000 PSI can get mighty pricey.
Your pump/engine setup will be sweet on a 5" ram.
Ignore the advertised tonnage of factory built splitters. Its a sales gimmick and almost NEVER will the tonnage rating be correct (there are a couple of companies that are honest).
Don't plan on building the hydraulics to obtain the 3000 psi relief pressure. You simply won't need that much pressure. I run a 5" ram also, and have the pressure set to 2750 psi. Unstoppable. You can only run up to the pressure of the lowest rated part. Components above 3000 PSI can get mighty pricey.
Your pump/engine setup will be sweet on a 5" ram.
Get a control valve with 3/4" ports. Check the orifices of the fitting you use some fittings have as little as 3/8" orifice for 3/4" hose. These restrictions are the major cause of heat.
Sounds like you're off to a good start with the pump/engine/piston setup.
Like Jags said the fittings are the most important - an 1/8"/1/4" reduction in inside diameter at these pressures become substantial orifices - orifi for those in the know
Mcmaster carries subpar compression fittings - I wouldn't recommend them for high vibration hydraulic applications - lots of firsthand experience here
Swagelok is pricier stuff but well worth it for assembly/disassembly and limited hydraulic leaks, Parker got the bid to tube the hydraulic skids on the GT's I work on and they nearly lost their behinds on warranty claims.
You probably want to stay towards SAE compression fittings on your hoses as they are easiest to source at the local hose shops
And somewhere above someone stated the filter was suction side of pump - putting one on the return makes a lot more sense for ~$25 TSC sells the housing and filter, unless you want to cavitate and damage the pump
Like Jags said the fittings are the most important - an 1/8"/1/4" reduction in inside diameter at these pressures become substantial orifices - orifi for those in the know
Mcmaster carries subpar compression fittings - I wouldn't recommend them for high vibration hydraulic applications - lots of firsthand experience here
Swagelok is pricier stuff but well worth it for assembly/disassembly and limited hydraulic leaks, Parker got the bid to tube the hydraulic skids on the GT's I work on and they nearly lost their behinds on warranty claims.
You probably want to stay towards SAE compression fittings on your hoses as they are easiest to source at the local hose shops
And somewhere above someone stated the filter was suction side of pump - putting one on the return makes a lot more sense for ~$25 TSC sells the housing and filter, unless you want to cavitate and damage the pump
Ram 1500 with an axe...
Minister of Fire
What? You want me to say... Bad luck?. HaWhy? It ain't rocket surgery or brain science.
It would have to be. He ain't running a single stage 22 gpm pump at 2800+ psi with an 11HP engine.
Caseihmech
New Member
I would have to say seeing a filter on the return side would be a first for me. You want your return to be a no restriction return. You want the oil exiting the cylinder as smoothly and easily as possible, back to the tank. Gear pumps have no problem sucking oil from the reservoir. If you were running a piston pump then you would need a gear charge pump. (but that's a discussion for another day).
Take a walk through your local HD/Lowes/Tractor Supply. Every last one of those units has it in the return, as does every non-homebuilt unit I've run across lately. It's in the return on my Iron & Oak as well.
The issue is cavitation which would occur when the filter gets clogged, restricing the intake of oil. Two fastest ways to destroy any hydraulic pump are cavitation and aeration.
Caseihmech
New Member
It would have to be. He ain't running a single stage 22 gpm pump at 2800+ psi with an 11HP engine.
Well true. Being around tractors all day long, there is no such thing as two stage pumps. You have gear pumps, piston pumps, gerotor pumps. But no two stage.
Caseihmech
New Member
I cant argue about the those two ways of damage a pump. But what are you doing letting the filter get clogged?
And a return that gets restricted also slow down the cylinder and also take out the pump.
These machines generate plenty of fine wood dust and have a vent somewhere on the tank to let it in. Every time you extend the cylinder you will have airflow into the tank.
In order for the return to build that much pressure, the filter bypass valve (built into the filter or the mount) would have to fail, the filter itself would have to withstand the operating pressure of the system (not happening) and the relief valve in the pump/control valve would also have to fail. Pretty unlikely compared to a clogged filter restricting oil flow into the pump.
Most filters start bypassing oil once they see a 10-20 psi pressure differential from one side to the other. The exact pressure required to start bypassing oil varies from filter to filter but they all are set well below the bursting point of the filter can.
Caseihmech
New Member
Having the filter return or the SUCTION side doesn't make a huge difference. ha. It all really comes down to how you take care of the machine. It can be done either way. Its more of a personal preference. 6 of one half dozen of the other.
A lot of people can not believe some of the poor maintenance stories I have seen. A cure for odd noises in tractors, turn up the radio. I have had a farmer tell me one time when he turned up the radio the noise went away. That was after we had to replace pump and a couple different valves. Another one a guy bought a brand new Case 821 wheel loader. 8000 hours later didn't understand why his transmission went out, this was after we told him the filter on his tranny and the oil in it was never changed since it was new.
A lot of people can not believe some of the poor maintenance stories I have seen. A cure for odd noises in tractors, turn up the radio. I have had a farmer tell me one time when he turned up the radio the noise went away. That was after we had to replace pump and a couple different valves. Another one a guy bought a brand new Case 821 wheel loader. 8000 hours later didn't understand why his transmission went out, this was after we told him the filter on his tranny and the oil in it was never changed since it was new.
Recent cust of mine was disappointed in his Deere 110 TLB. (Compact backhoe) It just didn't have all the power it should have had. And I was puzzled too until he told me "it's only got 1200 hours on it and I ain't had to do nuthin' to it till now!"
(That included oil/filter changes , the air filter was black!)
Caseihmech
New Member
We had one customer call us to do a service on a skytrac. Who also complained of low power. Come to find out the exhaust had some how broke or fell off of his turbo and was blowing all the smoke right at the air filter. And they kept running it. You talk about BLACK and packed full! Its amazing what some people have in there head when it comes to any sort of machinery.
Caseihmech
New Member
So, if the splitter will only see high pressure on the supply side (pump to valve, valve to cylinder, cylinder return to valve), are these locations where I should use high pressure JIC fittings? Anyone know if a good source? What about on the return? I see the timberwolf splitters use hoses with stainless hose clamps.
Noted on the restriction with regards to different fitting/hose sizes. How would I go with the following:
Cylinder has 7/8"-14 working ports
Pump has 1" outlet.
Most detent valve I can find (3000 psi rated & 22gpm) have 3/4" working ports. Anyone recommend a valve w/ 1" ports?
Noted on the restriction with regards to different fitting/hose sizes. How would I go with the following:
Cylinder has 7/8"-14 working ports
Pump has 1" outlet.
Most detent valve I can find (3000 psi rated & 22gpm) have 3/4" working ports. Anyone recommend a valve w/ 1" ports?
splitez has a 3/4" valve that handles 30 GPM with detent. http://www.splitez.com/hydraulic_valves.html
And to the OP - even at that - keep your eye on it. There are plenty of hydro hoses that are only rated to 2500 psi.
Should the pump be level or below the outlet port of the tank?
I don't see how it could be on the supply. Most filter housings I see are 200psi max. If on the return, can it be mounted just prior to entering the tank? I've seen them on the return side of the valve and to me, this would be prone to damage.
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