Problems with hydraulic machine vice
Problems with hydraulic machine vice
(OP)
We currently use 2 Homge hydraulic machine vices on our Hurco milling machines. They were a considerable investment some years ago and replacing these now would cost around £800 GBP. The problem we are experiencing is that they do not seem to get up to pressure.
The vice winds in manually on the main screw as it should do and once this reaches tightness it disengages the main screw and engages the secondary screw which winds the piston in to increase the pressure exetered by the jaws. This seems to wind in as it should. However when the secondary screw bottoms out which should be at optimum jaw pressure it is still possible to move the workpiece if struck not overly hard with a mallet.
I have looked at these vices myself and overhauled the entire mechanism on one of them. The slides appear to be in perfect service and parallel condition so no tipping occurs when they are tightened. The latch mechanism between the primary and secondary screws. The piston is in good conidition, fully bled of any air and it does not appear to be leaking any fluid since the main o-ring was replaced.
Does anyone have any further information or ideas about why these may not be making full pressure?
Many thanks
Veero
The vice winds in manually on the main screw as it should do and once this reaches tightness it disengages the main screw and engages the secondary screw which winds the piston in to increase the pressure exetered by the jaws. This seems to wind in as it should. However when the secondary screw bottoms out which should be at optimum jaw pressure it is still possible to move the workpiece if struck not overly hard with a mallet.
I have looked at these vices myself and overhauled the entire mechanism on one of them. The slides appear to be in perfect service and parallel condition so no tipping occurs when they are tightened. The latch mechanism between the primary and secondary screws. The piston is in good conidition, fully bled of any air and it does not appear to be leaking any fluid since the main o-ring was replaced.
Does anyone have any further information or ideas about why these may not be making full pressure?
Many thanks
Veero





RE: Problems with hydraulic machine vice
RE: Problems with hydraulic machine vice
The chamber is preloaded by a stack of Belleville spring washers, so Im wondering if these have become fatigued over time and are not providing enough initial pressure.
I will reply again with some for of sketch showing how the vice works.
Thanks
Veero
RE: Problems with hydraulic machine vice
Try to bleed it into a vacuum.
Mike Halloran
Pembroke Pines, FL, USA
RE: Problems with hydraulic machine vice
Don
Kansas City
RE: Problems with hydraulic machine vice
I agree you either have air in it, or a bad valve/seal somewhere in the system. The bellville's COULD be fatigued, but that does not sound like the problem here to me.