Tool unclamp noise

Hello.

I have a problem whit the toolchange in a MA40HA. It seems like the tool is not unclamped fast enough. The arm sometimes drags the tool out from the spindle whit a banging noise. I have taken the cylinders apart and checked the springs and the draw bar. It did not help. I bleeded the system and there seems to be no air in the hydraulic oil. The problem is present even whit a low tool change speed (25%).

Are anybody having a idea what the cause could be?

Could the hydraulic valve work too slow?

Thanks for any help!

Best regards, Samuel

Call a engineer, some of the MA40H has 2 stage unclamp cylinder, and a some of them has really difficult hydraulic system..

also inside drawbar there a some ruller pins, that rust.

My suggestion if yu are not sure about the mechanical parts then call local service.

Check the two collets loose. First unclamp and then use collet fixing tool.