Rotary drill bit with cutting insert for engaging earth strata
US9085947B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 2013 |
| Grant date | Jul 21, 2015 |
| Priority date | — |
| Expiry date | Nov 5, 2033 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/003
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A rotary drill bit for engaging an earth strata material includes a cutting insert attached to an axial forward end of an elongate drill bit body. The cutting insert includes an elongate insert body rotatable about a central axis with a pair of symmetrical halves symmetrical about the central axis, each symmetrical half comprising: a leading face; a top surface having a primary relief surface; a web thinning gash extending between the leading face and the primary relief surface, the web thinning gash having a debris evacuation portion centrally disposed adjacent the central axis and a distal transition portion disposed adjacent the debris evacuation portion; a first leading cutting edge at the intersection of the leading face and the primary relief surface; and a second leading cutting edge at the intersection of the web thinning gash and the primary relief surface of the top surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.