Method of joining reinforced thermoplastic pipes
US5824179A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 12, 1996 |
| Grant date | Oct 20, 1998 |
| Priority date | — |
| Expiry date | Mar 12, 2016 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2023/22
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
An electrofusion coupler is slid over one of two thermoplastic pipes, each having a layer or layers of reinforcing fibers between the center of the wall of the pipe and the outside surface of the pipe. The end surfaces are trimmed in a butt fusion machine and the resulting end surfaces are forced against a heater plate. The plate is removed and the end surfaces are forced together. Internal and external beads involving inward and outward flow of material result, the outward flow ensures that there is at the welded joint an inner layer which is free from reinforcement fibers. The external bead is removed and the coupler is slid over the butt fused welded joint and energized to cause it to become fusion welded to the outside of the pipe.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.