Rotary drill bit with cutting insert having edge preparation
US9428968B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 2013 |
| Grant date | Aug 30, 2016 |
| Priority date | — |
| Expiry date | Aug 6, 2034 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/58
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A rotary drill bit for engaging an earth strata material includes an elongate drill bit body having an axial forward end and an axial rearward end, and a cutting insert attached to the axial forward end of the elongate drill bit body. The cutting insert has an elongate insert body rotatable about a central axis and includes a pair of symmetrical halves symmetrical about the central axis, each symmetrical half including a leading face, a top surface having a relief surface, a T-land surface extending between the leading face and the relief surface and a cutting edge formed at the intersection of the T-land surface and the relief surface. The cutting edge can have a negative axial rake angle. The relief surface can include a primary relief surface and a secondary relief surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.