Method and apparatus for controlling the effect of contact impedence on a galvanic tool in a logging-while-drilling application
CA 2273554 C · Owner: Dion, Dominique · Inventors: Li, Qiming; Fredette, Mark A.; Hall, James Stephen
Overview
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Open the CIPO recordAbstract From the Canadian patent
The present invention describes a method and apparatus to control the effect of contact impedance on a formation resistivity measurement during a logging- while-drilling operation. The control of contact impedance is accomplished by maintaining a substantially zero difference in potential between two monitor electrodes positioned on the resistivity logging tool near a current electrode. The tool can employ a ring electrode configuration and/or a button electrode configuration. The ring electrode configuration incorporates two pairs of ring monitor electrodes on each side of a ring current electrode. The button electrode configuration incorporates a monitor electrode surrounded by a current …
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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 June 2, 1999 and granted May 20, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 2, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 2, 2021.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.