Methods of lining the internal surface of a pipe
US5873390A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 19, 1996 |
| Grant date | Feb 23, 1999 |
| Priority date | — |
| Expiry date | Jul 19, 2016 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16L55/38
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
There is provided a method of lining the internal surface of a pipe involving a larger diameter portion, said method comprising the steps of inserting a first pig into the pipe from an open end thereof, said first pig being a spherical body made of a resilient material having a diameter larger than the pipe inner diameter and having a number of grooves formed on the surface thereof for permitting air escape, injecting behind the first pig a necessary amount of resin into the pipe, inserting behind the resin a second pig into the pipe, said second pig having a diameter smaller than the pipe inner diameter such that a resin lining layer having a desired thickness may be formed on the internal surface of the pipe, providing a positive pressure and applying the positive pressure behind the second pig in the pipe, and causing the first pig, the resin and the second pig to move through the pipe along the entire length thereof by the positive pressure, so as to form a resin lining layer on the internal surface of the pipe by means of the second pig.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.