Bridgeport VMC 1000 oil pressure

[racerdog]

The lubrication system on this machine has a pump that cycles about 2 times an hour. As soon as it pumps some oil into the ways and the ball screw it stops. Sometimes during the machining cycle the alarm " Low oil pressure" flashes on the screen and the machine stops.
Do I need to tell the boss to get a new oil pump or is there some adjustment that can be made?
If we do need a new oil pump who would have one?
The boss just got this machine. Its a 1993 model. I just do not want to be responsible if it runs out of oil on the ways or the ball screw.
racerdog

[machintek]

Oil time ON and OFF are controlled by parameters (DX or heidenhain control?)
usually I set it up to 600 seconds off and 10 seconds on.
Is it consuming oil?
Can you verify if the oil pressure switch is changing state?
Note that typically the oil timer runs when it sees movement of axis.

George

[racerdog]

The machine has the Heidenhain TNC 2500B control. As far as I have been able to tell it is set up to only allow access to four or five basic parameters.
We probably need some kind of factory code to gain access to all the parameters.
Thanks for the info. I'll pass it on to the boss.
racerdog

[machintek]

Under the MOD key, code = 95148, ENT, gets you into the parameters.

George

[gus]

But do be careful......

I would 'guess' the pressure sensor is bad, but you can find the parameter for the lube pressure and shut it off.

Of course, teh lube pressure could actually be low...

[One of Many]

This could also be as simple as a brittle lube line failure dumping the oil off preventing it from building any pressure.

DC

[Riverside192]

Had the same problem with our VMC 800. It ended up being a cracked Lubrication Manifold inside the pump resevoir. $95.00 in 2003 to replace it. DropsA USA in Houston Texas had the new improved version made from a plastic that was not as brittle as the original. Hope this helps D.

[machintek]

Better yet, I had a service call on a machine that when the oil way above the crack, it would not fault out, I assume it prevented as massive a leak as when the oil level was below the crack, then it did give a pressure error. Find that problem quickly!
If a line is broken, it will pump the tank out pretty quick. Hence my question if it was comsuming oil.
Also sometimes, if the brand of oil is changed, the two oils are not compatable and may "snot" clogging all the metering units.

George

[One of Many]

Originally Posted by machintek Also sometimes, if the brand of oil is changed, the two oils are not compatable and may "snot" clogging all the metering units. George

I just heard about this issue with incompatible way oils. I understand that when Mobile Vactra is used, if it is changed, the new oils can cause the parafin wax to seperate out. I was told the little Bijur tanks will go cloudy milky white if this is the case. So, at least there may be some other indicators of the impending condition. No telling on non-transparent tanks, eh. Yikes!

DC

[racerdog]

Today (4/03/06) I checked out all the replies to my original question.
The machine is getting oil but just not enough of it. Still get the "Low oil pressure" alarm.
The lines are all new. No cracks or clogged lines.
Called up Heidenhain support to try and find out which parameter controls the oil pressure but they could not help me. They said it depends on how Bridgeport configured the lubrication system and that they did not have that information.
I have the manual with a list of the parameters but can't find anything pertaining to lubrication.
Its got the TNC 2500B control.
Anybody know the parameter that controls the lubrication cycle?
racerdog

[Riverside192]

With a crack in the manifold inside the resovoir it will still pump oil but it wont hold pressure and will bleed back into the resovoir causing the low oil fault. Take the top off the resovoir remove the manifold and look for a crack on the outlet side of the manifold. It was pretty hard to see untill I got it cleaned up and all the oil wiped off. As soon as I put a little air to it, the crack was easy to find. Good luck. D.

[mcwmah]

remove the tube that is the output point from the lube pump. Jam a ball bearing at the out let and see what happens. See if the pressure achieve 40psi. Then pressure switch and pump is o.k.If not there is a internal leak in the lube pump. Maybe the manifold is crack. If there is no alarm then you have a leak along the tubing to he machine. Hope will help u.