Method and apparatus for navigational drilling with a downhole motor employing independent drill string and bottomhole assembly rotary orientation and rotation
US5738178A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 17, 1995 |
| Grant date | Apr 14, 1998 |
| Priority date | — |
| Expiry date | Nov 17, 2015 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B21/10
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A subterranean drilling assembly for linear and nonlinear drilling. A downhole motor-based bottomhole assembly with a bit deflection device includes a torque compensation device and is secured to the drill string via a swivel assembly to permit independent rotation of the string and the bottomhole assembly. In the case of a drill pipe string, the string may be rotated continuously during both linear and nonlinear drilling to reduce drag. In the case of a tubing string, the bottomhole assembly is rotated by the torque compensation device during straight drilling. In both cases, the torque compensation device is employed to adjust TFO for nonlinear drilling when the bottomhole assembly is not rotated. In an alternative embodiment, a torque-sensitive clutch is employed in lieu of the torque compensation device to provide rotational orientation to, and rotation of, the bottomhole assembly.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.