Steerable magnetic dipole antenna for measurement-while-drilling applications
US8604796B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 12, 2011 |
| Grant date | Dec 10, 2013 |
| Priority date | — |
| Expiry date | Aug 1, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/30
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A steerable or non-steerable, magnetic dipole antenna for Measurement-While-Drilling (MWD) or Logging-While-Drilling (LWD) applications. The antenna elements use a hole arrangement in addition to grooves in a steel tool body, which is typically a drill collar. This antenna embodiment is extremely robust, meaning that does not significantly reduce the structural integrity of the tool body in which it is disposed. The antenna embodiment is also relatively wear resistant. The resultant magnetic dipole generated by this antenna is also electrically steerable in inclination angle from a common origin. A variable dipole moment inclination angle combined with independently measured tool rotation orientation during normal drilling allows the antenna to generate a magnetic dipole moment that may be directed at any three dimensional angle and from a common origin point at the centroid of the antenna. The antenna can also be embodied to be more sensitive to resistivity in a particular azimuthal direction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.