Shut=off valve fitting for long sealing life pipes in chemical plants - comprises corrugated cladding of poly:tetra:fluoroethylene in housing passage, with ring seals and laying surfaces of shaped opposite ends

摘要

The shut-off fitting for carrier pipes, and especially a closure flap, comprises: (i) a passage channel with a U-shaped cladding of elastomer material and especially PTFE; where: (a) the ring seals (7,8) and ring laying surfaces (18,19) have shaped end surfaces at the opposite ends; (b) the cladding has a slight corrugated shape in the radial peripheral zone of the shaft passage in the nominal assembly position of the housing; (c) the cladding has the same wall thickness at least over the whole base width; and (d) the shaft grip is formed through holes in the base.