Denford Software & Machines

Hi

I accidentally friction welded the drawbar to the end of the brauer unit plunger by powering up the spindle with the plunger down. They have since been separated however now when the command to activate the cylinder is given the cylinder will extend but not retract. I know the problem is with the cylinder itself as I have tested the pneumatic system with a brauer unit from another Triac, which worked fine.

I think that I have damaged the seals by heating up the unit during the accident. I can also see that some oil is leaking from the bottom of the unit- the brown substance in the second photo. Does anyone know what type of oil to top up the unit with and how to disassemble the unit to investigate further? The socket head cap screw in the photo just turns the whole plunger when I turn it. I can see a circlip at the bottom of the unit but I can't separate the threaded body of the cylinder from the steel mounting flange. Any advice would be greatly appreciated.
Thank you for your help

I am pretty sure I used to fill the cylinder with normal machine oil. You should be able to pull the ram out with an allen key & refill to the top of the tube.

Hi Martin
Thanks very much for the reply. Forgive my ignorance but how do you remove the plunger? If I try and turn the socket head cap screw with an allen key the whole plunger rotates in the cylinder.
Do you think 3 in 1 would work?
Thanks

If you put the allen key at a slight angle it should pull out.

3 in 1 should be fine.

Thanks Martin. So I hooked the ram out and topped up the oil, but when I reconnected it to the Triac Pneumatics it still wouldn't retract. However, when I disconnected the quick connect airline again it shot back up. Any thoughts on what that might mean? Too much oil/not enough, damaged seals? Any further help is really appreciated.
Thanks

It sounds like the solenoid is not letting the air dump. It may be worth activating the draw bar several times to see if the valve will free up.

Thanks Martin. Unfortunately the problem still persists.

Update. I'm going to try and replace the seals in the Brauer unit. Can anyone identify the type of seal/ring shown in the photo? This is the seal that attaches to the top of the plunger. It measures 41mm OD at the flared top, 33mm ID, 9mm wide there is a groove on the inside that measures 3mm wide that a feature on the plunger connects to. If it weren't for this internal groove I would think it a a standard U ring. Do any members know what it's called and where to look for a replacement?
Thanks

It could be a custom seal.

I'd think the best place to try would be somewhere that overhauls/repairs hydraulic rams.

Thanks Moray. A custom seal sounds worrying. I have contacted a supplier and will report back.