
Flanges and Fittings ISO-KF, ISO-K, ISO-F, CF
“Ultra-high Vacuum (UHV)” designates the pressure range below 10-7 ar. Several physical quantities, such as mean free path, monolayer time, flow density of the particles impinging on the walls, leak rate and the degassing rate are of significance in the charac ter-ization of this pressure range. For the definitions of these quantities refer to technical publiions on this subject. In