KAGRA VIS Operations Manual - Pumpdown and Venting Procedure

Pumpdown of the vacuum chambers causes large mechanical stresses which tilt the IPs and cause them to drift. Also, loss of buoyancy from the air on the suspended masses causes the GAS filters to sag. Similar changes happen in reverse on venting. Therefore it is necessary to monitor the suspensions during pumpdown and venting to correct any alignment issues before they lead to problems. See detailed procedures below.

Type A

Type B

Type Bp

Type C

KAGRA/Subgroups/VIS/OpsManual/PumpdownAndVenting (last edited 2019-05-02 16:21:20 by MarkBarton)