| 摘要 |
1397474 Grooving pipe ends JOHNS-MANVILLE CORP 27 March 1973 [31 March 1972] 14635/73 Heading B5A [Also in Division F2] A rubber gasket 24 and PVC support rings 26 are positioned on a mandrel 36 which is lubricated and/or heated. The end of a PVC pipe is heated to the range of thermoelastic deformability, and pushed over the mandrel 36 until one support ring 26 engages a mandrel collar 60, and the pipe end engages a mandrel end ring 56. External pressure and/or suction through a mandrel cavity 46 are applied. After cooling, e.g. by a cooling fluid, the pipe is pulled from the mandrel; the gasket 24 rides up a mandrel ramp 44 so that it and the support rings 26 remain within the moulded pipe groove 20. The pipe may be inserted on to, and removed from, the mandrel by apparatus as described in Specification 1,157,929. |
