hydraulic pumps rpm

[jomifo]

Hello-

I'm a newbie when it comes to hydraulics. I'm hoping someone here can give me some advice. I'd like to build a log splitter that works off the PTO of my BCS 2-wheeled tractor. The tractor has a 13HP Honda motor which I'm thinking has plenty of HP. The PTO runs at 990 RPM. From what I can tell, there don't seem to be many pumps out there that run at that low of an RPM. I've found a few searching the internet, but they all seem to be higher flow/lower pressure type pumps. My understanding is that I need higher pressures for a log splitter.

From what I've seen most of the pumps out there for this type of application are made to directly couple to a gas engine at around 3600 RPM. One option I thought was making a pulley/belt-driven jack shaft to double the RPMs to around 1980, but not even sure if there is a pump out there that would work well at that RPM.

Any advice on pumps, cylinders, or the feasibility of constructing a jack-shaft would be greatly appreciated.

Thanks,
Joe

 

[Yankee Clipper]

Jomifo,

Most hydraulic pumps need around 1000 RPM for the pressure plates to move against the side faces of the gears to seal and increase pump efficiency. Below that most gear pumps are not too efficient.

There were some gear pump made for use on air planters at 540 RPM, but they were made a bit differently - different pressure plates . Most applications will use a gear box to take a standard pump and speed it up so the running speed is above 1000 RPM.

Your idea of using a belt / pulley arrangement is likely the best as you can take a standard pump and get to where you need to be on speed. Don't lose sight of your rated engine speed and also high idle - remeber, it will be multiplied times whatever factor you use.

Good luck!

 

[dynasim]

Surplus center sells a whole range of pto speed pumps(meant to be directly mounted to the splines of 540 or 1000 rpm pto outlets). They have all different flow capabilities, so you could have your pick!

Others have used them with good success.

Chris