PIPE COUPLING

摘要

1462886 Pipe couplings I STRAUB 13 June 1974 [15 June 1973] 26340/74 Heading F2G A sealing gasket 21 incorporated in a pipe coupling 10 (Fig. 1) is of generally C-shaped cross-section with end edges constructed as sealing lips 23, 24 intended to bear against the respective pipe ends, the gasket 21 having a web 22, each sealing lip 23, 24 having a lip root and being supported at the web 22 by a substantially ring-shaped bead 31, 32 spaced axially from the associated lip root, the gasket 21 being provided with spaces 27, 271, 2711 to each side of the beads 31, 32, and the spaces being connected with one another by through passages 33 (Fig. 6). The gasket 21 is supported by a tubular housing 11 slit lengthwise at 12 and clamped by bolts 17 which interconnect a pair of rods 15, 16 held in the edges of clamping brackets 13, 14, the latter being welded to the housing 11. Each sealing lip 23, 24 is tapered towards a free end of minimum thickness remote from its lip root, the associated bead 31, 32 bearing only against the free end of a sealing lip, at least during such time as the housing is not yet clamped. To resist axial forces displacing the pipe ends away from one another, the housing has inwardly bent ends 19, 20 against which rest anchoring rings 29, 30 lamellated as indicated in Fig. 1 and in the shape of truncated cones so that the lamellae overlap at the inner diameter. The rings 29, 30 are supported at their outer diameter by resilient expandible rings 34 which each consist of a wire ring 35 around which is wound a helical spring 36 having tightly contacting coils. In operation, the pipe connection is sealed in the absence of internal pressure by virtue of the ring beads 31, 32 which press the sealing lips 23, 24 against the outer diameter of the pipes. As internal pressure in the pipe increases, the lips 23, 24 become deformed giving an increased sealing action and the lamellae of the anchoring rings 29, 30 are forced to claw into the outer diameter of the pipe to prevent axial movement. In an alternative embodiment (Fig. 9) suitable for use, e.g. where the gasket material has inadequate elasticity, a separate ring 38 of appropriate elastic material is provided having a bead 31 and a bulbous portion 41, and so shaped that it fits exactly into a complementary portion of a gasket 21. A compartment 271 is thus formed and is connected with compartment 27 by bores 33. The two components of this embodiment may conveniently be produced in vulcanization moulds for use especially with smaller diameter pipes, whilst the one-piece gasket may be formed from an extruded band and is more suitable for use in connecting larger diameter pipes.