Fire Wood Processor Hydraulics

[SCOOP56]

Building a firewood processor and have gathered most parts.
My attention is now to gather "hydraulics". I have 2 hydraulic motors to drive the chain saw and the log advance.
My splitter ram is 5" bore and 2" rod diameter, 24" stroke, 3500psi max.
My cylinders for log lift, holding bar, and saw pressure are 2 1/2 bore, 1 1/8 rod diameter 12" stroke, 2500 psi.
What size "pump" should I use? 2 stage?
Thanks Glen

 

[J_J]

What size engine do you have.

HP determines the pump you can use.

 

[SCOOP56]

4 cyl gas engine. 80hp.

 

[J_J]

Then you definitely can run the largest 2 stage pump Surplus has, a 28 GPM pump.

28 GPM DYNAMIC 2-STAGE PUMP

 

[oldnslo]

scoop56,
I would suggest you look at a sequence of operation to determine what functions will be running at what times.
Then estimate speeds and forces required for function.

Doing this will help determine if a single hi-lo pump will work or if you would have better performance using multiple pumps.

Example: one pump somewhat dedicated to the saw & log advance for a more controlled speed. Splitter, log lift & clamp, possibly one pump depending on how they cycle in respect to each other. My guess is you would probably get the best performance using a double pump with one section for saw & log advance, the other for lift and clamp. Use a totally separate pump for splitter.

 

[J_J]

Something like this maybe.

 

[muddstopper]

I would not recommend trying to run the hydraulic saw motor and all the other hydraulics with a 2stage wood splitter pump. A lot depends on what cuin size motor you plan for your saw. Your best bet is to run a double pump setup. One pump dedicated to the saw, and one, or possibly two, more pumps to run the splitter cylinder and the log lift, conveyor, or other accesseries. A good saw motor, will need 20+gpm to get the proper chain speed out of the saw your 2stage wood splitter pump will only make that kind of flow in the low pressure side of the pump. Pressure for saw motor will probably need to be in the 1800-2000psi min. range, again on the high flow side of you pump, you wont be able to build the pressure you need. A good case can be made for adding a third low volume pump to your system to power all the small cylinders. Yes you can rob oil and use flow controls and pressure reliefs to control the speed and power for the lift cylinders and bar cylinders, and the log advance (conveyor??) motors, but all those extra parts might cost more than say a 5gpm gear pump. Also, you will notice a performance drops in the speed of the saw, or splitter cylinder, if you decide to use a little of their available oil flow while sawing or splitting. In the future, you might decide to add a off feed conveyor to move the split wood, another oil robber. You have the hp to run the saw and splitter with plenty left over for add ons, even if you dont decide to add anything now, I would plan on it incase yo change yuor mind later on.

 

[glastron23]

muddstopper said it about the 2 stage pump is a real problem. If i had to do it over i would bite the bullet and buy a pressure/flow compensated pump, it would solve a lot of problems. we used a triple gear pump, 1 for the saw, 1 for the splitter and 1 for the rest of the hydraulic cylinders and advance motor.

 

[oldnslo]

glastron,
nice looking rig you have there.

 

[SCOOP56]

To everyone, thanks for the advice, certainly cures my queries.
Scoop56