| 摘要 |
1534547 Pipe joints MARSTON EXCELSIOR Ltd 10 Feb 1976 [5 March 1975] 9108/75 Heading F2G A joint between a pair of pipe ends 1, 2 which have been accurately machined to form cylindrical recesses 5, 6 comprises a cylindrical metal sealing member 7 which extends into the recesses 5, 6 and is an interference therewith, the ends 9, 10 of the member 7 being flexible so that under the influence of pressure within the pipe ends 1, 2, they will be pressed into sealing engagement with the recesses 5, 6. The ends 9, 10 of the cylinder are preferably of slightly greater diameter than that of the central portion 11 when the member 7 is not in place, and the material of the member 7 preferably has the same coefficient of thermal expansion as the pipes, advantageously by being of the same material. Flanges 3, 4 and bolts 14 are provided for holding the joint, alternatively a screw-threaded coupling member may be employed. An annular ridge 8 is provided on the member 7 for location purposes and a groove 12 is provided in the ridge 8 to facilitate withdrawal of the member 7. Also disclosed is a sliding expansion joint, Fig. 3, in which is provided a metal cylinder 30 having a smooth internal surface 5 in which slides a member 28 integral with a flexible metal sealing cylinder 30. An annular ridge 28a is disposed around the member 28 and this may ride within limits defined by a wall 34 and a flange 32 on a retainer screwed on to the wall 34. |
