Hydraulic pump info needed

So I have a very well built homemade hydraulic press that my grandfather purchased around late 1940s. The hydraulic pump has gotten very weak and needs to be replaced. It is an old Racine military surplus pump and no info on it is available that I have found so I would like to calculate what I could replace it with. Shaft size is 1" but I could always replace the half of my Lovejoy for a smaller shaft size. I do also have a couple of 5 hp motors but they are pretty much the same rpm.

My Ram is 2 3/8" dia. in a 6" dia. casing which is just over 32" long. My motor is a 3 phase 7.5 hp 1725 rpm. I would like to run at least 10 ton but maybe more if my setup would handle it.

I am mainly using it to bend 1 1/4" pipe but use it to press out bearings and straighten bent metal also. I have pics but do not know how to post them. Was looking at a Vickers or Eaton style pump. Also not sure if I should get a vane or gear pump.

10t in a 2.375" bore is going to land you around 4500psi. Not crazy high, but definitely at the point where you need to be paying attention to the strength of your fittings/hoses/etc.

Good luck!

EDIT- or maybe I read that wrong and it's a 6" bore with 2-3/8" rod. At that point you're done to 700psi and about anything will do what you want. I'd be looking for a logsplitter style 2 stage pump. To reduce cycle time.

If the ram rod diameter is 2.375 and the hydraulic cylinder inside diameter is 6" then at 1200 psi you would get around 33,929 push and 28,613 pull. At 1500 psi then 42,411 push,35,766 pull. These numbers are approximate and only for reference. The 7.5 horse power motor is great for your application. the size of the pump really depends to some degree with on how fast you want the ram to travel. Gallons per minute. You may also want to add a flow divider to control ram no load travel speed.
My 100 ton press uses a Baldor 8 H.P that coulpled through a love joy Commercial Shearing gear pump and flow divider, my control valve relief pressure is set at 25,000 psi. At my business all presses are gear pumps, we haven't use vanes in years.

Thanks. Yes, the ram rod is 2.375 and cylinder is about 6" outside diameter. I'm concerned about the rpm being lower as the pumps I have spotted are for 3000 or 3600 rpm, or is that just their max rpm? I am also using a hand valve for operation if that's what you are meaning. Any idea how I can post pics? I think the 1500psi would be nice as that would get me 20 tons. Where is a good place to purchase? It would be online as there aren't much for hydraulic suppliers in my small town.

69stang said:

Thanks. Yes, the ram rod is 2.375 and cylinder is about 6" outside diameter. I'm concerned about the rpm being lower as the pumps I have spotted are for 3000 or 3600 rpm, or is that just their max rpm? I am also using a hand valve for operation if that's what you are meaning. Any idea how I can post pics? I think the 1500psi would be nice as that would get me 20 tons. Where is a good place to purchase? It would be online as there aren't much for hydraulic suppliers in my small town.

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Pumps are fine running under speed. If you know the gear displacement in CCs you can calculate GPM and get your travel speed.

As for buying, check out Baum Hydraulics in (Kansas?), or Federal Fluid Power in Mt. Pleasant, MI. We have used both of them and they are good with helping out.

...also, Surplus Center is a good choice for hydraulic supplies. Located in Nebraska.

I just ordered a Vickers knockoff vane pump from them. 22 gpm for $242. They've got all kinds of pumps.

For this press, you could just as easily use a vane type pump. That's probably what is in your current unit.

PS~ If you request it, they'll send you their printed catalog. It's worth getting, just browsing through it you can find things you didn't even know you needed and will wonder how you got along without them all this time, LOL.

another place to look for hydraulic parts is Northern Hydraulics, I think they're in Minnesota?

Most of the wear in Hyd pumps happens in the end plate faces. Many times, lightly milling or grinding the end plates to re-surface them flat and smooth again will restore performance. It's the low cost solution. Been there, done that.