hydraulic relief valve to cut torque

[DesignerMike]

I have a high torque low-speed hydraulic motor that will produce excessive torque in a new application. I can't cut the system pressure, and prefer to re-use the motor I have. NOTE: It's a closed center constant pressure system.

I believe I can put a relief valve inline before the motor to cut the working pressure to my motor (and stall the motor at a given torque).

System pressure is 3000 psi, I require ~ 1500 psi to hit my torque limit. IF I put an adjustable relief valve set to 1500 psi before the motor. I believe I can assume that the relief valve is simply working of the pressure differential and when the motor requirements hit 1500 psi and the pressure relief adds 1500 psi, the circuit would dead-head and stall?

Using the adjustable relief would give me the option to fine-tune the torque output. I understand that I will be adding some additional heat to the circuit since the relief would be bypassing during "normal" operating conditions and it is not the best way to do it. It's low flow around 2.2 gpm.

On the other hand, the correct size motor may cost less than an adjustable relief valve.

 

[budt]

A Relief Valve can be piped to work but a Reducing Valve in the line to the Motor is what should use.

There will still be some heat generation but it will be a LOT LESS than a circuit using a Relief Valve.

Also you can still use excess pump flow to operate other functions since the only reduced pressure will be at the Hydraulic Motor Inlet.


Bud Trinkel CFPE
HYDRA-PNEU CONSULTING, INC.
fluidpower1 @ hotmail.com

http://www.fluidpower1.us

 

[hydromech]

I'm in agreement with Bud.

A reducer is the way to go...

 

[DesignerMike]

I didn't even think about that.

I use them all the time in water, compressed air, and steam applications... But I don't use "hydraulics" very much anymore, and didn't consider it.

Thanks