Method of forming a welded joint between polyolefinic members
US5296073A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 24, 1992 |
| Grant date | Mar 22, 1994 |
| Priority date | — |
| Expiry date | Apr 24, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S285/909
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A polyethylene pipe 10 is joined by a welded joint to a cross-linked polyethylene coupler 14 which has been expanded to make the coupler heat recoverable. Radiant energy (eg light in the visible spectrum or infra-red light) illuminates the outer surface of the coupler 14 supplied by an array of 15OW reflector lamps 20. The coupler 14 shrinks and is forced into engagement with the pipe 10 and the pipe 12 to join the pipes. A fusion welded joint is formed between the coupler 14 and each pipe, 10, 12. In an alternative a pipe is drawn down and inserted in an aperture through the wall of another pipe. A lamp is inserted in the drawn down pipe and the radiant energy causes the pipe to expand into engagement with the edge of the aperture and to be joined to it by a welded joint (FIG. 2).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.