Wood Splitter Calculations

[AlinCalifornia]

Hello all.. I am putting together a log splitter and I would like to get some expertish advise.. The parts I have are a new 9 H.P. motor,,16 G.P.M. 2 stage pump,, Cylinder is 24 inches long,, 22.5 inches around and the bore is 14.750....I would like to know what the pressure would be when I am done..The new 2 stage pump says it is good for 33 tons,, So would that be the max splitting force? Also does anyone have or know of where I can get a piece of H beam or 4 x 6 X 3/8'' tubing? If that would be heavy enough?,, would rather find used 95215 area..Here is a picture of the cylinder and valve..Thank You for any and all input

 

[walkerdogman85]

The surface area of your cylinder piston determines your tonnage, also it depends on what psi your control valve is set on! Go to the Baum hydraulic calculator on the Internet and roughly figure it. What size is the bore, rod, and stroke?

 

[FLRA_Dave]

Not sure on the accuracy (maybe someone can edit it if its off and repost???). I put it together to get some rough ideas going.

Updated link...

https://www.dropbox.com/s/4wrtvswn72r28t2/SPLITTER_GPM_VS_HP_VS_FORCE.xlsx

 

[dave_dj1]

You will have to figure out your bore and rod diameters, then use this:
Hydraulic Cylinder Calculator

The larger rod size will give you a quick return stroke too.

 

[FLRA_Dave]

Hello all.. I am putting together a log splitter and I would like to get some expertish advise.. The parts I have are a new 9 H.P. motor,,16 G.P.M. 2 stage pump,, Cylinder is 24 inches long,, 22.5 inches around and the bore is 14.750....I would like to know what the pressure would be when I am done..The new 2 stage pump says it is good for 33 tons,, So would that be the max splitting force? Also does anyone have or know of where I can get a piece of H beam or 4 x 6 X 3/8'' tubing? If that would be heavy enough?,, would rather find used 95215 area..Here is a picture of the cylinder and valve..Thank You for any and all input

I'm getting lost on the sizing as shown... Should it be 2.25 inches in diameter and the rod at 1.475 inches in diameter?

 

[AlinCalifornia]

The surface area of your cylinder piston determines your tonnage, also it depends on what psi your control valve is set on! Go to the Baum hydraulic calculator on the Internet and roughly figure it. What size is the bore, rod, and stroke?

Ok I did some math so here is what I come up with..The cylinder looks like it is 7 inches,,the bore is 4.75...Stroke 24 inches...Main question is since the pump says 33 tons,, will that be the limit??

 

[FLRA_Dave]

Ok I did some math so here is what I come up with..The cylinder looks like it is 7 inches,,the bore is 4.75...Stroke 24 inches...Main question is since the pump says 33 tons,, will that be the limit??

Your pump does not determine the tonnage. It's the PSI produced by the pump x Area of the cylinder... as previously stated.

 

[nathon918]

Ok I did some math so here is what I come up with..The cylinder looks like it is 7 inches,,the bore is 4.75...Stroke 24 inches...Main question is since the pump says 33 tons,, will that be the limit??

NO.

having a tonnage rating on a pump is retarded.
it should have a pressure rating. your pump pressure and cylinder bore determine tonnage!
you could put a huge cylinder with any pump and generate 100's of tons of pressure

most 2 stage pumps will put out 3000 psi max, and with a 5 inch cylinder it will put out just under 30 tons.

 

[Steve NW WI]

I was thinking that as well, 4 3/4" bore, assuming the first post dimensions were circumference. Also, if the 22.5 is the outer circumference of the cylinder, you need to subtract wall thickness of the cylinder, probably about 1/4 - 1/2" (per side) leaving you with a 6, maybe 6.5" diameter cylinder. Tonnage - great plenty. Use the baum hyd calc link above to figure it out exactly if you'd like.

The pump only affects tonnage based on how much pressure it puts out. It might be 33 tons on a 5" cylinder, but the same pump would put out much less tonnage on a smaller cylinder, or more on a bigger cylinder.

To put it simply, if you change any one part in the system, this is what happens:

Less GPM, slower speed, more GPM higher speed
Lower pressure, less tonnage, higher pressure, more tonnage
Smaller cylinder - higher speed, less tonnage. Bigger = lower speed, higher tonnage

 

[Fifelaker]

I was thinking that as well, 4 3/4" bore, assuming the first post dimensions were circumference. Also, if the 22.5 is the outer circumference of the cylinder, you need to subtract wall thickness of the cylinder, probably about 1/4 - 1/2" (per side) leaving you with a 6, maybe 6.5" diameter cylinder. Tonnage - great plenty. Use the baum hyd calc link above to figure it out exactly if you'd like.

The pump only affects tonnage based on how much pressure it puts out. It might be 33 tons on a 5" cylinder, but the same pump would put out much less tonnage on a smaller cylinder, or more on a bigger cylinder.

To put it simply, if you change any one part in the system, this is what happens:

Less GPM, slower speed, more GPM higher speed
Lower pressure, less tonnage, higher pressure, more tonnage
Smaller cylinder - higher speed, less tonnage. Bigger = lower speed, higher tonnage

But it looks like it has a radial on one side and a bias ply on the other. Wouldn't that skew any tonnage specs???:jester:

 

[Cheesecutter]

For your beam you could try craigslist or a salvage yard may have it. They may also have other steel use could use. I found my beam at a farm auction, and my buddy who works at a welding shop was able to pick up scrap flat stock for scrap price.

 

[Steve NW WI]

But it looks like it has a radial on one side and a bias ply on the other. Wouldn't that skew any tonnage specs???:jester:

Better for twisted grain. I'll find a pic of my splitter when I get home tonight. Been using that setup a long time.

 

[twinfiddles]

Rating on the pump is only the maximum it can produce. System pressure is determined by the relief valve in the control valve. All components must be rated for at least that pressure.

 

[Mac88]

But it looks like it has a radial on one side and a bias ply on the other. Wouldn't that skew any tonnage specs???:jester:

Since they appear to be installed on a steer axle, you can fix that by adjusting the toe-in on the appropriate side.

 

[Steve NW WI]

Better for twisted grain. I'll find a pic of my splitter when I get home tonight. Been using that setup a long time.

What'd I tell ya? Note that the OP's tires are even on the correct side. Radial on the left, bias on the right. Helps counteract the torque generated when splitting crotches.

Note to OP - we're just having a little fun here with another thread - it's just BS.