Apparatus for directional drilling
US5421421A · kind A · utility
Inventor
Key dates
| Filing date | Jul 12, 1993 |
| Grant date | Jun 6, 1995 |
| Priority date | — |
| Expiry date | Jul 12, 2013 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B7/06
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A downhole steering tool comprises a hollow mandrel (11), an independently rotatable sleeve (12) extending over a portion of the mandrel (11), steering plungers (26) carried by the sleeve (12) and extendable and retractable laterally to and from pressure contact with the hole wall (28) for steering a drill below the tool when in use, releasable locking means (14) for locking the sleeve (12) to the mandrel (11) rotationally, and fluid control means (15) operable to direct to the locking means (14) and the steering plungers (26) a portion from fluid circulation through the mandrel (11) to release the locking means (14) and to extend the steering plungers (26) by means of pressure of the fluid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.