compressed air issue?

[Brisli]

Hi everyone,
we are experiencing issues with our machine valve gate valves and our gripper circuit valves on our robots. our compressed air goes thru a dessicant dryer and then thru a series of filters before going to the floor. upon inspection of the failed valves, the grease on the spool is gone. any ideas why this could be happening?

Thanks.

[rickbatey]

I don't think air valves use grease but a light oil. Some shouldn't be lubricated at all. But maybe you need to change grease or even the valves. How are you cleaning the valves?
On valve gates I believe you should have an accumulator to stop from starving the pneumatic operation. Are you sure you have enough air volume out of the drier and filters to carry all those systems?
Rick.