Plug apparatus and method for cementing a liner in a well bore
CA 2035289 A1 · Owner: Fraser, James M. Iii · Inventors: Fraser, James M. Iii
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention provides an apparatus for cementing a liner string in a well bore. The apparatus comprises an operating string having a smaller diameter than the internal diameter of the liner string which is insertable therein. The operating string is connected within the internal diameter of the liner string and may be operated by rotation of the operating string to release the string from the liner. A plug is connected to the lower end of the operating string and has a top plug which is releasably supported from the plug carrying body together with a longitudinally spaced bottom plug which is releasably supported from the top plug. The top plug is pressure releasable relative to …
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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 January 30, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 30, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 30, 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.