Logging method and apparatus for acoustic inspection of a borehole fitted with casing
CA 2014875 C · Owner: Schlumberger Canada Limited · Inventors: Wright, Peter
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Method for determining at least one characteristic of a casing cemented in a borehole, such as cement bond and casing thickness from a reflected, acoustic signal S(t) obtained by directing an acoustic pulse at a substantially normal incidence towards a radial sector of the wall of the casing, said pulse stimulating thickness resonance within the walls of the casing. The method according to the invention comprises the steps of : defining a first time window corresponding to a first portion of signal S(t) including the initial reflection from the casing and subsequent acoustic returns due to resonance, defining a second time window corresponding to a second portion of signal S(t) only …
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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 April 19, 1990 and granted December 7, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 19, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 19, 2012.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.