Rotary drill bits
US4848491A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 19, 1987 |
| Grant date | Jul 18, 1989 |
| Priority date | — |
| Expiry date | Nov 19, 2007 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/46
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A drill bit for drilling deep holes in subsurface formations comprises a bit body having a generally hemispherical leading face and a gauge region, and two blades each extending spirally outwardly across the leading face of the bit body away from the axis of rotation, a cavity of substantial peripheral and axial extent being formed in the bit body on the forward side of each blade, and communicating with an associated exit channel in the gauge region. A plurality of cutting elements are mounted along each blade, the cutting elements being mounted closely adjacent one another side-by-side along the blade so that their cutting edges together form a single long cutting edge without substantial discontinuities. A passage in the bit body supplies drilling fluid to nozzles in the cavities for cooling and cleaning the cutting elements, fluid from the nozzles sweeping past the cutting elements and out through the exit channels.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.