Method and apparatus for transmitting information to the surface from a drill string down hole in a well
US6714138B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 29, 2000 |
| Grant date | Mar 30, 2004 |
| Priority date | — |
| Expiry date | May 25, 2021 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B47/20
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method and apparatus for transmitting information to the surface from down hole in a well in which a pulser is incorporated into the bottom hole assembly of a drill string that generates pressure pulses encoded to contain information concerning the drilling operation. The pressure pulses travel to the surface where they are decoded so as to decipher the information. The pulser includes a stator forming passages through which drilling fluid flows on its way to the drill bit. The rotor has blades that obstruct the flow of drilling fluid through the passages when the rotor is rotated into a first orientation and that relieve the obstruction when rotated into a second orientation, so that oscillation of the rotor generates the encoded pressure pulses. An electric motor, under the operation of a controller, drives a drive train that oscillates the rotor between the first and second orientations. The electric motor is located in an air-filled chamber whereas the major portion of the drive train is located in a liquid-filled chamber. The controller controls one or more characteristics of the pressure pulses by varying the oscillation of the rotor. The controller may receive information …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.