System of drilling deviated wellbores
US4577701A · kind A · utility
53Cited by
10References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 8, 1984 |
| Grant date | Mar 25, 1986 |
| Priority date | — |
| Expiry date | Aug 8, 2004 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B7/068
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Directional drilling is carried out with a rotary drilling tool having a drill string, a drill bit, a drill motor for rotating the drill bit independently of the drill string, and a bent sub affixed between the lower end of the drill string and the drill motor for angularly displacing the axis of rotation of the drill bit from the axis of rotation of the drill string. Both the drill string and drill bit are rotated to provide a straight path for the wellbore, while only the drill bit is rotated during the deviation of the wellbore from a straight path.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.