Horizontal boring apparatus and method
US4993503A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 1990 |
| Grant date | Feb 19, 1991 |
| Priority date | — |
| Expiry date | Mar 27, 2010 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B47/13
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Boring apparatus for forming a generally horizontal underground passage for a utility conduit or the like that includes a tool head with elongated body structure and a cutting face of ellipto-conical form at one end of the elongated body structure. The cutting face has a major axis and a minor axis and cutting bit structure is fixed to and projects forwardly from the cutting face and extends substantially the full width of the cutting face generally along the major axis. The tool head also includes coupling structure for attaching the tool head to a drill string such that the cutting tool face is offset from the drill string axis. Structure in the cutting face defines a cutting fluid orifice adjacent the cutting bit structure for directing a high velocity jet of cutting fluid forwardly of the cutting tool face. The tool body is adapted to be advanced and concurrently driven in rotation to move the cutting face in orbital boring action about the drill string axis to bore an underground passage and to be advanced without rotation to produce a change in direction of the underground passage in the direction of offset from the drill string axis.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.