Process for replacing a length of buried pipe
US5013188A · kind A · utility
Inventors
Key dates
| Filing date | Apr 17, 1990 |
| Grant date | May 7, 1991 |
| Priority date | — |
| Expiry date | Apr 17, 2010 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16L55/1658
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The process comprises excavating pits at the first and second ends of a buried section of old water main pipe that is to be replaced with new pipe. The exposed segments of pipe are broken up to provide access to the bore of the old pipe. A pipe splitter and a cylinder-actuated pulling unit are installed in the first pit. A string of rods is extended through the old pipe bore from the first pit to the second pit. A tool assembly of sequentially connected components is attached to the second end of the rod string. The tool assembly may comprise: means for centralizing the second end of the rod string in the second end of the old pipe section; a pull plate for bearing against the annular second end face of the old pipe section; a cylindrical plug for expanding the passageway extending between the pits; a rod member for extending through the bore of the new pipe section to be installed; and a second pull plate for bearing against the annular second end face of the new pipe. The new pipe section is mounted on the rod member and the string of rods is tripped to the first pit. In the course of tripping or retracting the rod string, the following actions simultaneously occur: the old pipe …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.