Honing machine spindle is falling down

[Andrzej Skrzypczyk]

Dear Colleagues,

the issue is related to hydraulic system in the honing machine.
The spindles of this machine are moved up and down by hydraulic cylinders - two cylinders on each spindle.
There are three spindles on this machine and the problem with falling spindle occurs only in one of them.

The issue is that when the hone head (tool) has to be changed one of the spindles is slowly falling down
when others are still in their places. The falling is about 30-40 mm per hour.

I've attached the hydraulic schematic of spindle system.
Elements 1-4 are exchanged by new ones - we type them as an issue.
After changing those elements and also check the fitting of all hydraulic connections the problem still occurs.

Do you have any ideas what can be the issue in this system?
All suggestions will be appreciated.

 

[btrueblood]

Leaky piston seals on the cylinders?

 

[Andrzej Skrzypczyk]

Leaky piston seals on the cylinders?

I forgot to mention that: All seals in cylinders have been changed already.
Our troubleshooting considered that.

 

[IRstuff]

"I forgot to mention that: All seals in cylinders have been changed already. Our troubleshooting considered that."

Just because they're "new" does not automatically give them a pass. The seals could be damaged, or the sealing surfaces could be damaged. If I were to apply Occam's Razor, I would spend a lot of calories on this before declaring them eliminated.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529

 

[3DDave]

There is a leak. You should be able to disconnect lines to the valves that are supposed to be closed on their downstream sides and see if fluid is escaping. Obvious cautions about doing something that is inherently dangerous. if you cap the exhaust port on the cylinder that would see if the piston seal was a problem.

 

[Andrzej Skrzypczyk]

Thank You Guys for all your replies.

I'm going to perform "on field" tests mentioned by 3DDave.
Next step will be check of the quality of "new" seals.

 

[Andrzej Skrzypczyk]

Dear Colleagues,

before we started do find the leakeage in the first spindle the second spindle also started to fall down.
I'll let you know about my experience on this case.