Anti-rotation device for cementing plugs with deformable peripheral "fins" or "lips"
CA 2045441 C · Owner: Buisine, Paul · Inventors: Lavaure, Gilbert; Buisine, Paul
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Used for exploitation of oil or similar wells. - The device includes a tubular portion . designed to be interposed between the lowermost element of a casing (1) and the bottom holding sleeve (3) . made of a material with a strong friction coefficient and easily drillable by a drilling tool . delimiting, from its bottom opening (7a) on an internal, convergent (11) opening into a straight section (12) with a diameter substantially equal to or lower than that of the plugs (13, 14) in the prestressed state of the lips and having, from said section on, a bore (15) with the same diameter as the latter, extending over an axial length at least equal to that occupied by at least two plugs in …
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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 25, 1991 and granted July 23, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 25, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 25, 2013.
- 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.