Method and apparatus for determining the in situ larmor frequency of a wellbore nmr tool to compensate for accumulation of magnetic material on the magnet housing of the tool
CA 2117990 C · Owner: Freedman, Robert · Inventors: Smaardyk, John E.; Mac Innis, Jason P.; Freedman, Robert
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A system includes a wellbore tool disposed in a wellbore and a surface apparatus disposed at a surface of the wellbore. Prior to operating the tool to take an initial measurement the wellbore tool is first calibrated to take into account magnetic junk which is magnetically attracted to and accumulated on a magnet housing of the tool. To calibrate the tool a new tuning frequency, called the Larmor frequency is determined, and the tool is tuned to the new Larmor frequency before taking an initial measurement. The wellbore tool and the surface apparatus each include a processing system. Each processing system includes a memory. A first part of a tuning frequency determination software is …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed October 12, 1994 and granted July 6, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 12, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 12, 2016.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.