Composition and method for cementing a well
CA 2071722 C · Owner: Riley, Wendell D. · Inventors: Riley, Wendell D.; Childs, Jerry D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention is concerned with a composition for and method of performing primary cementing operations. The method comprises the use of a water slurry of a thixotropic cementing composition which rapidly develops sufficient static gel strength to reduce if not eliminate annular gas migration. The thixotropic cementing composition comprises hydraulic cement water, an alkali, metal aluminate and an alkali metal halide.
Read the whole patent
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 19, 1992 and granted November 21, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 19, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 19, 2014.
- 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.