Fixed displacement radial piston hydraulic motor wants a new home

[CJ12]

Hello, I come from a farming background and recently a powerharrow's gearbox (tractor pto driven) failed.

I am interested in replacing the gearbox with a hydraulic motor, however you may be able to advise me on whether this is practical given the available pump output and data. Reasons for this are to reduce machine wear from shock loads, and to explore applications for hydraulic power.

I have a tractor with a pump output from svc of 25.1gpm (95lpm) reservoir of 19.8 gal (74.9 l) in a pressure flow compensated system.

I have found on fleabay a fixed displacement 30.48 in3/rev (500 cm3/rev) radial piston motor (max speed 400 rpm) from a 100 tonne injection moulding machine that is cheap but may be too big for my pump.

https://www.rkr-hydraulika.cz/katalogy/Pleiger/MO_05 EN.pdf

I need a rpm speed close to the range of 30 - 60 rpm from the motor. Horsepower requirement from motor will be 40 - 70 HP if that is relevant.

I am concerned that I do not have enough flow to prevent cavitation or that simply a fixed displacement motor will not work here, or the bits and bobs required to make it work will be too expensive?

I can make the flow calculations work out, though this is dependent on the rpm slowing down to match the max fluid flow available, and the system pressure being high enough to give an adequate volumetric efficiency.

Any help appreciated!

 

[hydtools]

Too many things do not match. At 25gpm the motor will turn 189rpm, not 30 - 60. At 25gpm and 2000psi you have 29hp available, not 40 - 70.

Ted

 

[CJ12]

Thanks for reply Ted, I will go back to sourcing some enhanced bearings for the original gearbox.

If anything, I've learned a bit more about fluid flow.