Determining the pressure of formation fluid in earth formations surrounding a borehole
CA 2478136 C · Owner: Schlumberger Technology Corporation · Inventors: Pierre, Stephane; Dussan, V. Elizabeth B.; Trittschuh, Jennifer
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for determining formation fluid pressure in earth formation surrounding a borehole wall uses a downhole probe coupled to a variable-volume cavity. The probe is driven into contact with formation at the borehole wall. The method includes expanding the volume of the cavity during a first period of time to establish fluid communication between tool fluid and formation fluid by withdrawing a minimal amount of fluid from the formation. During a second period of time the tool pressure is allowed to equilibrate to formation pressure. When pressure equilibrium is established formation fluid pressure is set equal to tool pressure. A preferred embodiment includes terminating expanding the …
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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 August 17, 2004 and granted July 10, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 17, 2024.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 17, 2026.
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