Gerardo, Travis, Jordan, Sean (GNB tech)

Today a tech from GNB came to the site to perform maintenance on the air cylinder for GV7 after we were unable to hard close the valve, see alog 89625

We first soft closed GV8 (and replaced the faulty air regulator) as a safety during the GV7 work. We then marked and measured the positions of the reed switches on the cylinder threaded rod, then disconnected the top air line. Sean then disassembled, cleaned and replaced all of the seals in the cylinder head, and the top and bottom flanges. We did have to modify the wear band since the one in the repair kit was too long and the ends overlapped. We also installed the new cylinder, but the used one looked to be in good condition. We will keep that one as an emergency spare.

New grease was applied to all seals and the inside of the cylinder. In order to keep the seals and wear band contained while installing the cylinder, Sean used a plastic band around the cylinder which kept the seals in place as the cylinder passed over them, which was then removed once the cylinder made it past the top piston seal. The top flange was then installed, along with the reed switches and air line.

The valve was already soft closed during the repair, so to test we wanted to see if we could hard close. We noticed there was no longer any air leaking from the solenoid manifold, and we heard the audible "thunk" of the valve camming over (hard closed) at 40 psi, we confirmed the cds screen showed red for the valve status indicating the valve was hard closed. We then re-opened GV8.

No significant issues encountered, just a lot of cleaning of the old grease and seal grooves.

Full set of pictures/videos will be posted to the DCC and linked to this alog.

Closing WP 13256