Retrievable center bit
US7520343B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 8, 2005 |
| Grant date | Apr 21, 2009 |
| Priority date | — |
| Expiry date | Feb 8, 2025 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/64
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A retrievable center bit for use with a tubular including an inner bore and a drill shoe cutter mounted thereon. The retrievable center bit may include a body positionable in the bore of the tubular and including an upper end, a lower end and a side outer surface extending therebetween. A cutting surface may be supported on the lower end of the bit body. There may be a locking assembly on the body for releasably locking the bit axially and rotationally to the tubular. A longitudinal bore may extend from the upper end into the body and the body may include a fluid port extending from the bore to open on the cutting surface and a lateral fluid port extending from the bore opening on the side outer surface positionable adjacent the drill shoe cutter when the bit is locked to the tubular.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.