Abstract
Five types of already developed flanges for sealing ultra-high vacuum namely gold wire flat type, gold wire corner type, “Conflat”, “Curvac”, and aluminium foil bend type, are examined to make clear of the points which ensure the vacuum tightness, that is to know the dimesional allowance, tightening force, baking temperature. The new aluminium foil type UHV flange, named “Groovac” was developed in our laboratory, and conventional vacuum flange standardized as Japanese Industrial Standards (JIS) can be used as the female flange. The other male side flange was designed to have single or double semi-circular projections or flat cross-section. Connecting these two, it was proved to have good performances in UHV and even in liquid nitrogen temperature. Aluminium foil gasket of 1, 0.05, and 0.02 mm thickness could be used in repeating 300°C baking, and besides -196°C cooling.
