Anyone know what this hydraulic pump is or how it works?

This topic has 7 replies, 6 voices, and was last updated 19 June 2017 at 17:15 by Howard Lewis.

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15 June 2017 at 12:33 #302662
Ian Parkin
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@ianparkin39383
I bought this hydraulic pump to try and run my press

It has a 3 phase motor driving the pump it has one outlet and a solonoid valve near the outlet..Am i correct in thinking that if i connect the outlet to my ram and run the motor it will pump oil at a pressure and when the motor stops it will hold the pressure…when the solonoid is energised it will let the oil return to the tank?

Also how do i check rotation of the motor…there's an arrow but no visible shaft or fan….if it pumps out the outlet that must be correct rotation? Or do i need to buy a phase rotation meter? New toy ?

Edited By Ian Parkin on 15/06/2017 12:33:43

Edited By Ian Parkin on 15/06/2017 12:34:43

Edited By Ian Parkin on 15/06/2017 12:35:42
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15 June 2017 at 12:33 #8752
Ian Parkin
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@ianparkin39383
15 June 2017 at 14:13 #302675
J Hancock
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@jhancock95746
If this is a positive displacement pump , take care !
15 June 2017 at 14:32 #302677
Ian Parkin
Participant
@ianparkin39383
Well i have connected it up and it all works as i expected pumps one way doesn't the other so direction surely be ok. However on my new 30ton ram it only pumps it up to 10 tons on the dial which is calibrated for a 75mm dia ram…no actual psi readings

But I'm pleased with it nice and quiet and fast on the ram…

Does anyone know what sort of machine something like this would be on?

Mr Hancock whats wrong with a positive displacement pump and what am i likely to have?
15 June 2017 at 14:50 #302680
not done it yet
Participant
@notdoneityet
Pressure is force multiplied by area. You have both area and force indicated so you should be able to calculate the pressure. It must have an internal pressure relief valve. Whether that is adjustable or not is not clear. It is unlikely to be adjustable by a factor of three, mind. Depends on motor power and flow as well as pressure.

You could change your ram for one of three times the area and recalibrate the scale!
15 June 2017 at 14:51 #302681
Alan Waddington 2
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@alanwaddington2
Looks very similar to a 12v one i had running a small Hiab on my trailer. There was an allen key adjuster to up the pressure. When i first piped it up it wouldn't lift anything over 400kg, but once the screw was adjusted it easily did 800kg. I'm guessing it was some form of internal bypass.
15 June 2017 at 15:20 #302684
John Rudd
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@johnrudd16576
The likelihood is that you have a gear pump or vane type pump.

Dead heading a positive displacement pump is not good for the motor or pump internals ( conrod/crank), could result in burning out the motor if the motor protection doesnt work, or bent parts in the pump itself, usually protected by a relief valve….

For a more comprehensive guide on hydraulics have a read here……

https://en.m.wikipedia.org/wiki/Hydraulic_pump
19 June 2017 at 17:15 #303238
Howard Lewis
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@howardlewis46836
Failure modes if you increase the pressure: could be a burned out motor, (may not be immediate but could happen gradually) or if the pump is the first point of failure, the key / keyway in the drive shaft / rotor / gear may be the next.

Beware of sudden leakage of high pressure oil. It could be dangerous; penetrating flesh, and possibly causing blood poisoning Think what a jet of oil at 5,000 psi would do to an eye.

My suggestion, if needed, would be to do initial runs with a sheet of something substantial between you and the unit when testing it after adjustment

Sorry to be so dismal, but no point in injuring oneself.

Howard
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