Directional drilling methods and apparatus
US5139094A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 1, 1991 |
| Grant date | Aug 18, 1992 |
| Priority date | — |
| Expiry date | Feb 1, 2011 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B7/068
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Methods are provided for controlling the direction of a borehole drilled by a downhole motor, including the steps of positioning downhole adjustable bent housing and near-bit stabilizer in the drill string, adjusting the bent housing from its normally straight condition to its bent condition to effect borehole curvature, and using the stabilizer in its undergage condition to enhance the inclination. The Measurements are made from which the inclination with respect to the vertical and the azimuth can be determined and telemetered uphole for processing, display, and recording. Preferably the directional measurements are made at two locations, one below the bent point and one above it. These two sets of measurements can be compared to confirm the bend angle and to obtain a definition of the orientation of the plane of the bend angle so that the drilling path can be accurately controlled. Use of the present invention eliminates having to superimpose rotation of the deflected drill string in order to drill straight ahead because the bend angle can be eliminated by downhole adjustment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.