tail edge of the plate coming out of the clamp during the run

i have a problem with the tail edge of the plate coming out of the clamp during the run.
its PQC so there are no spanners involved.
The clamp seems to go through all its motions ok when putting a plate on, then BANG it goes at some random point when you think its all running sweet as.
Take all off manually etc, then back to square one.
it does this approx twice a shift on me.
Ive never altered anything regarding "fan out " etc.
Any ideas

 

PQC is the remote console, I think you mean semi-APC. Have you reset your clamp pressure yet? Is it confined to one unit? Have you tried mounting manually? Are your plates the right size? Shorter plates (even by a couple of m)m will have a hard time staying locked in the clamp.

 

yeah the semi APC.had a word with my shift partner, he says when he puts the plate on that unit he loosens the 4 allen screw bolts on the back edge before he puts. the plate on.It never comes off for him???. il try that..but surely i shouldn't be doing this as its an APC not a manual clamp. How would you go about resetting clamp pressure.

 

What!!! Those 4 are for setting clamp pressure and that's a one time thing.

The clamp is closed (and opened) by the air-piston on the operator side. No wonder your plates are coming out. Slap his wrist and tell him to leave the darned thing set.

 

I've never had to do it but I guess you'd loosen the cap screws, cut a plate down to around 200mm and insert it into a clamping section, close the clamp manually and tighten the cap screw until you can't pull the plate out. Repeat for all clamps... then take the adjustment key away from your shift partner ;-)

 

cheers for all that info, ive had the an engineer in today and got the clamp working perfectly after about 3 hours on it! allot of crap inside the shaft at the back of the tail edge clamp with was causing it not to properly open and close, sorted now... only thing is its doing it on the 4 th unit now.at least i know where to start!