Apparatus for replacing mains
US4720211A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 4, 1986 |
| Grant date | Jan 19, 1988 |
| Priority date | — |
| Expiry date | Aug 4, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T225/371
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
An apparatus for replacing an existing buried pipe of a crackable, fracturable material. The apparatus has a fracturing structure which applies an intense local pressure to crack and fracture the existing buried pipe into irregular fragments. This fracturing structure can include one or a plurality of blades, some of which may be retractably and expandably movable. The structure which exerts the intense local pressure is also operable to effect at least some outward movement of the fragments. An expansion structure moves the fragments radially outwardly, generally about the axis of the existing main, to provide a passage for a replacement tubular assembly. The apparatus is moveable through the existing main by the action of either a pushing or a pulling force, and the pushing force may be applied by percussive action.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.