Reducing or preventing dissipation of electrical current and associated magnetic signal in a wellbore
US9938819B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 2016 |
| Grant date | Apr 10, 2018 |
| Priority date | — |
| Expiry date | Apr 22, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/16
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An artificial toolface reference system includes a power supply providing current to a ground lead and a reference lead. A ground point is coupled to the ground lead and in electrical connection with the ground. A reference wellbore includes a reference conductor in electrical connection with the ground. The reference conductor is in electrical connection with the reference lead. The reference conductor includes an uninsulated portion and an insulated portion having an insulating layer positioned thereabout. A guidance sensor positioned outside the reference wellbore includes at least one magnetometer. The power supply may be used to provide a current through the reference conductor, into the ground through the uninsulated portion, and the ground point such that a reference magnetic field is generated along the reference conductor. The guidance sensor may measure the reference magnetic field with a magnetometer. An artificial magnetic toolface may be calculated therefrom.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.