Percussion drill bit and a regrindable cemented carbide button therefor
US7207402B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 26, 2003 |
| Grant date | Apr 24, 2007 |
| Priority date | — |
| Expiry date | Dec 1, 2023 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/56
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A percussion drill bit for drilling a bore includes a drill body having a connecting section at a rear end thereof for connection to a percussive unit, and a plurality of cemented carbide buttons embedded in a front end of the drill body. Each button comprises a cemented carbide body having a rear mounting portion embedded in the drill body, and a front end protruding from the drill body. The front end of the cemented carbide button is substantially semi-spherically curved and defined by a radius whose origin is disposed axially rearwardly of a plane through the largest diameter of the button. The button projects from the drill bit body a distance which is not less than 50% of the button diameter. A conical intermediate surface forms, in cross-section, an acute angle of about 13–19° with an envelope surface of the rear mounting portion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.