Method and apparatus for plugging and cutting a gas line or the like without excavation
US4295494A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jul 16, 1979 |
| Grant date | Oct 20, 1981 |
| Priority date | — |
| Expiry date | Jul 16, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49735
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A method and apparatus of sealing and cutting an underground pipeline, such as a gas line or the like, at or near a point where it connects to a main utilizes an expandable plug which may be inserted in the line without the need to excavate to obtain access to the point of sealing. A thermally stabilized cross-linked preshrunk polyolefin plug is inserted into the line on a heater element. The plug may be inserted from a point where the line exits the earth. Once the plug is inserted on the end of the heater element, the heater element is heated causing the plug to expand fitting it tightly inside of the line at or near the main. The heater element may then be withdrawn, and the line may be cut adjacent the inserted plug.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.