chandra.romel@LIGO.ORG - posted 14:54, Tuesday 22 March 2016 - last comment - 08:22, Wednesday 23 March 2016(26191)
Diagonal annuli pumping
John, Chandra Connected aux pumping carts to the following annuli: 1. HAM 7/8, with secondary turbo Pressure: 3.4e-5 Torr 2. HAM 11/12, with secondary turbo Pressure: 9.5e-5 Torr 3. HAM 9, no secondary turbo Pressure: 7.0e-4 Torr Still need to connect BSC4 annulus. Two annuli systems are leaking, based on the attached plot of diagonal gauge PT-140. Leak rate (O) e-3 Torr-l/s.
Images attached to this report
Comments related to this report
Tuesday evening: all three pressures on annuli are now low e-5 Torr range. I closed each turbo valve individually to see if pressure would rise in diagonal (on PT-140). No observed changes in pressure over 10 min time span for each. We have greatly reduced the leak rate by reducing pressure in the annuli.