Copper gaskets

Each face of the two mating flanges (referred to as CF or ConFlat flanges) has a knife edge, which cuts into the softer copper gasket, providing an extremely leak-tight, metal-to-metal seal. The gaskets are punched from high purity, oxygen-free copper having the ability to withstand high temperatures (up to 450°C) without leaking. Such high temperatures are used during the instrument cleaning (bake-out).

The picture shows copper gaskets having outer diameters of 48.1 - 171.3 mm that were originally part of the instrument ZAB-EQ manufactured by VG Analytical LTD. in 1986.