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hydraulic power pack question

hydraulic power pack question

hydraulic power pack question

i might be in the wrong place with these questions. but im looking to build a hydraulic press. to use when forging .
there are lots of designs’ out there on the web and i think i have most of it all figured out apart from the power pack i have acquired for free
it came off a large road barrier system. operated by a key card system.
and im guessing that the hydraulic ram must had a spring return ram [ that and the Wight of the retractable barrier]
as on the power pack i have there is only one hydraulic line going out .
i have got a photo here and just a have a few questions as the people at the local merchants weren’t much help at all
SO FEEL FREE TO TELL ME I HGAVE IT ALL WRONG as im just trying to logically work it out from scratch

form the photo im assuming that that it operates this way
"D" is my line out , activated by
"C" a 24v solenoid
"E" is a return path to the oil chamber . the valve im told was so they could keep the barrier down during events
[leaving it open would create a bypass ]
"B" behind the cab there is a screwdriver slot? is that for adjusting pressure ?
"A" is another 24v solenoid and i have no idea what’s it does
the gauge is stuck at 600spi but i imagine that’s the static amount of pressure when it’s all switched off
i have re pipeed it , so instead of "C" there is just a gauge on it . the pump ran and didn’t sound any different , i don’t know if there is air in the line and needs priming somehow. or it is something to do with solenoid A needing to be open ?

i intend to have a set up were the pump feeds a shuttle valve [ came off an old tractor ] that can feed a ram to open / close
made with all new hoses and with some thick 15mm angle iron i have
although the gauge only goes to 14000 psi i assume the adjustment on "B" will get me more ?
apart from the motor there is no spec on the unit.
i can find on line, a v simmiler unit for the same intended use inc motor ,has a small 1.1kw 3~ motor will run at 25000 which is more what i think need get ram with about a 4" diameter to be able to get me about 15 ton of force which is the min i will need really

if anyone can give me some advise on this it would be great

RE: hydraulic power pack question

It would be easier if you drew out the circuit because it is difficult to see what is connected to what.

However as far as I can work out,
A appears to be a solenoid which combed the motor output shaft to the hydraulic pump.
B could be the internal pressure relief valve or some sorry of volume flow control
C I think is the return flow back to the oil tank
D is your outlet and return fliw hose
E with the quarter turn valve is actually the high pressure feed from hydraulic pump. I guess that when they manually turned it closed then even if the card was activated and solenoid A activated then there was no flow and it would all go through the pressure relief valve B

I think your guage is just broken.

That's my best guess but some more amnesty might explain it a bit more.

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