Apparatus and method for drilling boreholes
US5679894A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 10, 1995 |
| Grant date | Oct 21, 1997 |
| Priority date | — |
| Expiry date | Oct 10, 2015 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B47/12
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The present invention provides a drilling system for directional drilling of boreholes. The system contains a drill string having a drill bit driven by a positive displacement mud motor. Sensors placed at selected locations in the drill string continually measure various downhole operating parameters, including the differential pressure across the mud motor, rotational speed of the mud motor, torque, temperature, pressure differential between the fluid passing through the mud motor and the annulas between the drill string and the borehole, and temperature of the circulating fluid. A downhole control circuit having a microprocessor and nonvolatile memory processes signals from these sensors and transmits the processed data uphole to a surface control unit via a suitable telemetry system. The surface control unit is programmed to operate the drilling system or aid an operator to control the drilling operations in any number of modes in response to the information provided by the various sensors. The system also provides means for monitoring the wear condition of the mud motor and to estimate the remaining life of the mud motor during the drilling operations. The drill string also pre…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.