Reports until 16:32, Wednesday 06 November 2013
LHO VE
kyle.ryan@LIGO.ORG - posted 16:32, Wednesday 06 November 2013 (8407)
GV6 leak repair attempt
Kyle, John 

We desire to repair a "legacy" leak on the 1.33" CFF on the north side of GV6.  Our preference is to vent GV6's annulus volume and remove the flex line portion of the external piping (redundant) to this joint and just install blank flanges in place of the removed flex line -> Unfortunately, we weren't able to get GV6 to close enough to vent GV6's gate annulus volume to do this.  Even after 70 psi was applied to the top of the pneumatic piston, GV6 never indicated "RED" or "hard-closed".  Furthermore, introducing small amounts of air into the combined annulus volumes via the vent orifice of the small turbo connected to the annulus pump port resulted in PT124B and PT114B increases which verified the fact that GV6 isn't sealing when closed.  

We will discuss options tomorrow but for tonight we restored the nominal state with the exception of leaving the YBM turbo valved-in and IP5 valved-out