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kyle.ryan@LIGO.ORG - posted 12:08, Tuesday 14 July 2015 - last comment - 11:56, Tuesday 21 July 2015(19621)

Leak hunting at Y-mid

Kyle, Gerardo 

0850 - 0900 hrs. local -> In and out of Y-end 

Kyle, Gerardo 

Connected LD to exhaust of Y-mid turbo and sprayed helium on turbo fittings -> Found that this turbo has a "Leak valve" a.k.a. a solenoid vent valve which is either not connected or absent altogether on the site's other Main Turbo Pumps (MTPs) -> The turbo had been left levitated but not spinning since John W. and Gerardo's earlier investigation -> As such, this vent valve would be open -> Found that the clamp for the blank on this valve was loose -> Tightened -> With the turbo levitated but stopped, the QDP80 running but valved-out, safety valve and turbo bypass valve opened we sprayed the turbo's CFF and NW fittings with no obvious "smoking gun" -> It is likely that tightening the blank on the vent valve may have been the leak on the turbo side of the 10" gate valve 

For our next session we will vent the turbo volume and remove and replace the vent valve with a blank followed be a leak testing of the CFF joints on the Y-mid volume

Also, set IP9 to Fixed 7000V -> This leaves only the X-mid still in Step Mode (currently 5000V)

Comments related to this report

kyle.ryan@LIGO.ORG - 11:56, Tuesday 21 July 2015 (19788)

Link

Upon noticing the vent valve mounted on the Y-mid turbo, Gerardo and I examined the X-mid turbo and found that it's vent valve was not installed.  Knowing that we would never use it and not ever noticing it on any of the other MTPs, I assumed that the Y-mid having one installed must be the exception.  Since then, I have surveyed the MTPs at the Corner Station and found that they too have them installed, albeit blanked off like the MTP at the Y-mid.  Thus, the X-mid MTP is the exception not the Y-mid MTP