Abstract: Vacuum support for a burst protection device of graphite, which support is a graphite disc formed by a multiplicity of graphite rings, each of which consists of at least two parts and has a prismatic cross section, the prism surfaces being inclined relative to the plane of the disc.

Abstract: Seal in a column with one or a plurality of trays in which the trays have at their periphery circular recesses in the form of a circular slot. Profiled seals resting against the wall of the column engage in the recesses. The trays have blind holes which at a distance from the periphery of the tray extending down through the circumferential surface through the circular slot. Locking means, preferably wedges, engage in the blind holes to press with adjustable pressure, the profiled seals against the wall of the column.

Abstract: A flexible graphite laminate produced by compacting expanded graphite having incorporated an alkali metal salt containing at least one of the elements chromium, molybdenum and tungsten. The alkali metal salt reduces the corrosive properties of the flexible graphite laminate. The alkali metal salt may be incorporated during or after manufacture of the flexible graphite laminate from graphite.

Abstract: Method and apparatus for joining together edge surfaces of polytetrafluoroethylene material by a butt joint in which abutting surfaces of the material are placed in a chamber bounded by clamps along the abutting surfaces which press together the abutting surfaces, and heating elements in the space between the clamps to heat both sides of the material between the clamps, the boundaries of the chamber inhibiting the volume expansion of the material resulting from heating. Pressure generated in chamber may be controlled by moving a heating element. Additional pressure during cooling-down is exerted on the butt joint by moving one clamping in the direction of the butt joint. A thin foil of a fluorine-containing thermoplastic inserted between the abutting surfaces facilitates joining of the surfaces.