Log splitter hydraulics issues...

mrcaptainbob · Nov 26, 2009

Need some guidance. I turned the (very) old log splitter into a kit. I believe the only parts useable are the filter and the cylinder. Will be using them in the new splitter. I did read the glossary info provided (thanks, J_J) in another thread (Vickers Pump) and came away somewhat educated. Sure appreciate the help on that. My question now is about controlling the cylinder. It is a 4" x 20" four bolt, double acting cylinder. It also has an extra 1/4" port at each end. Can/should these ports be plugged? Also, to keep it as a double acting cylinder, which type of control valve can I use? I like the feature of power return so I can chain yank a stuck piece of elm when necessary! I'd like to maximize the power on this cylinder, of coarse, so how can I determine how much is okay? I will check on the available engines I have, but am pretty sure I can come up with at least a 10 HP vertical shaft. So, next question....as previously recommended, a two stage pump is in my best interest. How can I determine the best model, GPM and pressure-wise for what I want to achieve?
Thanks again for all the help and guidance.

IceStationZebra · Nov 26, 2009

Bob - "It is a 4" x 20" four bolt, double acting cylinder. It also has an extra 1/4" port at each end. Can/should these ports be plugged?"

Can't you just plumb it like it was on the old splitter? It sounds like you have a generic Agricultural tie-rod type cylinder. These often have two sets of ports to accommodate different installations. They could also be bleed ports. A picture would help a lot.

Bob - "I like the feature of power return so I can chain yank a stuck piece of elm when necessary!"

The cylinder will not retract otherwise - unless you mount it so the cylinder is pointing up and use gravity to retract it.

Bob - "I'd like to maximize the power on this cylinder, of coarse, so how can I determine how much is okay?"

You need to find out what the pressure rating is. The cylinder should be marked somewhere, or you have to find the manufacturer and part number. Most ag cylinders are rated for 3000 psi, but some of the larger ones are only 2500pri. If you assume wrong you can kill somebody, or at the very least bend the cylinder rod.

Bob - "How can I determine the best model, GPM and pressure-wise for what I want to achieve? "

(gpm x psi)
----------- = hp
1714

cid/rev x rpm
------------- x eff = gpm
231

see "www dot hydraulic-supply.com/pdf/1455.pdf" for more formulas.
Haldex Barnes pumps are factory set to switch from high flow/low pressure to low flow/high pressure once the line pressure exceeds ~650psi. The pump/motor relationship depends on the max operating pressure, which also affects your available force.

16gpm nominal
1.034 cid/rev @ low pressure = ~15.3gpm @ 3600rpm = ~5.8hp @ 650psi
0.258 cid/rev @ high pressure = ~3.7gpm @ 3600rpm = ~6.5hp @ 3000psi/5.4hp @ 2500psi

22gpm nominal
1.395 cid/rev @ low pressure = ~20.7gpm @ 3600rpm = ~7.8hp @ 650psi
0.465 cid/rev @ high pressure = ~6.7gpm @ 3600rpm = ~11.8hp @ 3000psi/9.8hp @ 2500psi

ISZ

J_J · Nov 26, 2009

mrcaptainbob,

With a 10 hp engine, you can use this pump, and this valve and some hoses and a small reservoir. If you have two ports on each end, then plug the one you do not need. Just preference.

https://www.surpluscenter.com/item.asp?UID=2009112605581626&item=9-1390&catname=hydraulic

https://www.surpluscenter.com/item.asp?UID=2009112605581626&item=9-7724&catname=hydraulic

mrcaptainbob · Nov 27, 2009

Great info. I will post pictures late Friday eve. Will try to find info on that cylinder.
Sure appreciate the help.

Hope ya'll had a great Thanksgiving....

mrcaptainbob · Nov 27, 2009

Here are some pics of that cylinder. Have not cleaned it up (obviously!).
The first is a giant chunk of steel with quite a few oil circuits in it. The large center hole is the entry for the end of the cylinder. At the upper left of that are two 1/4" ports. Each was connected directly to the 1/4" ports on the cylinder body shown in the next picture. The last picture shows the end of that cylinder that mated with that giant chunk of steel. Will clean it up early part of next week. Hopefully some info will show from that.

IceStationZebra · Nov 27, 2009

That is an industrial style cylinder. I haven't been around too many of them so I don't recognize it but two major brands are Eaton and Parker (both of which have bought out many other brands in the past years).

BTW that is the first time I have seen the cylinder ports go into the barrel and not the end plates. I wonder if this was a one-off special or a "field" modification?

ISZ

mrcaptainbob · Nov 27, 2009

I have no idea, IceStationZebra. The guy who built it passed away last year and any info along with him. I suspect that end plate the bolts thread into was an add on to mount it to that 'GCoS'. There are side ports in the original base that are plugged. Maybe the original end plate was bored out for this setup....