Large ultra-high-vacuum VAT gate valve with viton gasket for the VIRGO interferometer

摘要

A 1.2 m diameter vacuum gate valve has been built by VAT as the first of a series of four, to equip the 2×3 km arms of the VIRGO interferometer. A Parker viton ringΦ = 15 mm, l = 4 m was submitted to a special heat treatment in air and in vacuum at Orsay before being inserted into the gate valve. The results tests on air tightness and on hydrogen, fluorine, and hydrocarbon outgassing carried out on the first gate valve are presented.