Rock drill bit with back-reaming protection
US6116357A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 9, 1997 |
| Grant date | Sep 12, 2000 |
| Priority date | — |
| Expiry date | Sep 9, 2017 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/24
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A drill bit for boring a bore hole in an earthen formation comprises: a bit body having a pin end, a cutting end and a longitudinal bit axis and including at least two legs extending from the cutting end, each of the legs including a bearing that rotatably supports a cutter cone. The bit body further includes a fluid flow system, including a flowway in said pin end that is in fluid communication with at least one exit port in the cutting end, the exit port being defined by a nozzle boss and disposed adjacent one of the legs. Each of the legs includes a leading side surface, a trailing side surface, and a center panel, and at least one of said legs is asymmetric such that its trailing side surface is larger than its leading side surface. The present bit can also include a lubricant system that has its opening in the trailing side of the leg, and can further include various wear resistant coatings and inserts on its surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.