Design of pump, prv, dir. valve to operate a double acting cylinder.
Design of pump, prv, dir. valve to operate a double acting cylinder.
(OP)
Hi all.
I have a practical question, to work with a double acting piston cylinder (1m Stroke length).
If i want to have a cylinder velocity of 0.5m/s, run by a Internal Gear pump operated with a 4/3 valve, and a prv.
1.Is having a pump displacement of 1.5e-4 m3/rev feasible ? alongwith
2. a PRV operating at Pmax= 3e+007 Pa?
3. Hence the pressure that develops in the hoses goes around 5e+7Pa ?
Are these good values practically????
I want to adjust these 1,2, 3 values to depict a real hydraulic system. The problem is if i try to make the hose pressure to be around 3 e7 pa then I have to operate prv at 1e7 pa and then the pump displacement goes really high. (4e-4 m3/rev to achieve 0.5 m/s ) and I cant calculate/design the hoses drops as no equation is available. Peter here suggests to use some equation for calculating pressure drops but i cant find any relevant scientific papers on it. Please suggest ....
Regards,
Sara.
I have a practical question, to work with a double acting piston cylinder (1m Stroke length).
If i want to have a cylinder velocity of 0.5m/s, run by a Internal Gear pump operated with a 4/3 valve, and a prv.
1.Is having a pump displacement of 1.5e-4 m3/rev feasible ? alongwith
2. a PRV operating at Pmax= 3e+007 Pa?
3. Hence the pressure that develops in the hoses goes around 5e+7Pa ?
Are these good values practically????
I want to adjust these 1,2, 3 values to depict a real hydraulic system. The problem is if i try to make the hose pressure to be around 3 e7 pa then I have to operate prv at 1e7 pa and then the pump displacement goes really high. (4e-4 m3/rev to achieve 0.5 m/s ) and I cant calculate/design the hoses drops as no equation is available. Peter here suggests to use some equation for calculating pressure drops but i cant find any relevant scientific papers on it. Please suggest ....
Regards,
Sara.





RE: Design of pump, prv, dir. valve to operate a double acting cylinder.
150 cc/rev is a pretty big gear pump (something like a size 6 Bucher pump) - and though I've seen these running into 300 bar reliefs, the fluid warms through pretty fast when you do.
A
RE: Design of pump, prv, dir. valve to operate a double acting cylinder.
I cant really have a high pump displacement Im sure of that, now i have to adjust the prv and hose pressures.
RE: Design of pump, prv, dir. valve to operate a double acting cylinder.
I'll attach a simplified schematic of a real system of roughly similar scale I was working on recently:
The compensating valve is set to no more than size or seven bar, and unloads the pump when you don't need full working pressure,
When you load the system up, pressure from the shuttle valve stops off the compensator, allowing the pump to develop full pressure
When you hit the stops, the Main Line Relief limits the pressure to 200-300 bar.
The counterbalance valve stops the load running away from you when you try to let it down (your system will struggle with this)
You can ignore the POCV, which isn't necessary in your example application.
A.
RE: Design of pump, prv, dir. valve to operate a double acting cylinder.
RE: Design of pump, prv, dir. valve to operate a double acting cylinder.
Is this a school assignment?
Patricia Lougheed
******
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