Friction-reducing drill pipe component
US6655477B2 · kind B2 · utility
8Cited by
7References
33Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 27, 1998 |
| Grant date | Dec 2, 2003 |
| Priority date | — |
| Expiry date | Apr 5, 2018 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B17/1064
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The friction reducing drill pipe component in the form of a sub (10) is adapted to form part of a drill string. The sub (10) comprises a tubular mandrel (12) having first and second ends for connection to adjacent components of the drill string. A sleeve (18) is mounted on the mandrel (12), and first and second stops on the mandrel (16, 20) restrain the sleeve 18 against axial movement relative to the mandrel (12). One of the stops (20) is removable or retractable to permit the sleeve (18) to be removed over the first end of the mandrel.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.