Drilling apparatus and cutter
US4865137A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 22, 1988 |
| Grant date | Sep 12, 1989 |
| Priority date | — |
| Expiry date | Apr 22, 2008 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/22
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An underreamer including a body having a bore therethrough, an arm mounted at its upper end to the body, a sleeve member detachably secured to the lower end of each arm and adapted to receive the frictional wear caused by the rotation of the conical cutter mounted thereto. Bearings and seals disposed between the cutter and the sleeve member provide smooth rotation of the cutter. In addition, locking pins and bearings extending between the arm and the sleeve member secure the sleeve on the arm. The arms are pivotally mounted in slots in the body and mechanical structure is provided for moving the arms to their cutting position with their lower ends positioned radially outward from the body.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.