Method and composition for cementing in a wellbore
CA 2022845 C · Owner: Carpenter, Robert B. · Inventors: Jones, Richard R.; Carpenter, Robert B.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of cementing in a wellbore penetrating subterranean formations characterized by mixing a predetermined quantity of Portland Cement containing at least 2 percent by weight of tricalciun aluminate: at least 2 percent by weight of gypsum; and 0.3-2.0 percent by weight of polyvinyl alcohol with enough water to form a pumpable slurry; pumping the slurry to a desired location in the wellbore and allowing the slurry to harden to a solid mass. Also disclosed is the composition. These methods and composition provide a cementing that has many advantages and beneficial results as delineated in the specification.
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 August 8, 1990 and granted February 13, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 8, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 8, 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.