With Ta#64 installed , TM4 HS line was helium pressure tested at TCS. base leak rate is 0.0XE-9 atm.cc/sec. HS line tested leak rate is 3x E-7 atm.cc/sec on 5 minutes 50 psi helium testing. Leak check result wasgood at NHC by helium spray method. We decided to apply water to HS and all other water lines still. The vacuum status is closely being watched. So far, TCS pumping down trend is still good. HS line supply water valve was switched on and off couple of times at TCS IG1 1.15 XE-6 range, and no vacuum spike was observed. More information will be logged in during the TM4 and target conditioning stage at TCS. |