Pipe for relining underground pipelines
US5148837A · kind A · utility
40Cited by
15References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 8, 1991 |
| Grant date | Sep 22, 1992 |
| Priority date | — |
| Expiry date | Jan 8, 2011 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16L55/1656
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
Pipe for relining underground pipelines, which is of the composite type having an annularly rigid corrugated outside wall (10) of polymer material, which is connected to the outside surface of a smooth inside wall (11) which consists of a thermoplastic elastomer so that it can be stretched and compressed. According to the invention there is provided on the inside of the smooth inside wall (11) a thin layer (13) of the thermoplastic having a lower frictional coefficient and/or greater wear-resistance than the material of the inside wall.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.