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variable displacment gearpump resolotion

variable displacment gearpump resolotion

variable displacment gearpump resolotion

I have developed a variable displacement control valve this valve relates to variable diplacement hydraulic pumping.  
advantageously when this variable displacement contol valve arrangement is used with a fixed displacement pump (gear Pump)
the variable control valve arrangement provideds variable displacement operation similar to that provided by a variable displacement pump (piston pump) in wich the flow and presure can be controlled by a machine operator
When the hydraulic opperation of the machine is not in use the pump will lower its flow rate and idle.
Pilot pressure from the manual hydraulic valve (valve bank) enables the valve to opperate the pump at full pressure until it is released by the machine opperator the pump goes back to idle


RE: variable displacment gearpump resolotion

So you have not developed a variable flow gear pump...just a valve that dumps oil when pressure is not required. This is called an unloading valve...a pilot operated unloading valve.

Where is the question?


RE: variable displacment gearpump resolotion

Yes you could call it some type of unloading valve,Our valve worke
diffrent we have a 25 bar constant pressure and the rest of the flow are dump back to tank,once the monoblock valve are activated
flow and pressure required incresed accordingly to load sensing  ,We have fitted our valve with a parker P365 gear pump on Sandvik Exera 206 Drill rig and it worked Very good(Replace the
Rexroth A10V100DFR 1/31 SERIES, We have chosen the P365 as the maximum pressure on the gear pump are 240 bar and Sandvik exera
pressures are 230Bar on the Rexroth Pump

RE: variable displacment gearpump resolotion

So...does your valve bring anything above what already exists with load sensing?

You don't seem to be asking any questions or brining new ideas. It's more like advertising the fact that you have put a valve on a gear pump.   

RE: variable displacment gearpump resolotion

Have you run this system at partial flow and partial pressures?
How is the heat generation?

+1 on teds comments. Sounds like an ordinary on/off unloading system, which is great. But not a substitute for variable pump if partial loads are required.  

RE: variable displacment gearpump resolotion

I'd jump on the bandwagon but it's getting kind of full... ISZ

RE: variable displacment gearpump resolotion

Try running a gear pump or fixed displacement pump using a servo motor.  Then you have control.
Then you can control flow or pressure and even limit the both so power stays within limits.

In this case the hydraulics are nothing more than means of transmitting power from one place to another like a flexible drive shaft or chain.

Peter Nachtwey
Delta Computer Systems


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