Cementing apparatus
CA 2021932 C · Owner: Davis-Lynch, Inc. · Inventors: Coone, Malcolm G.; Ehlinger, Jeffry C.; Cole, Frank
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Apparatus is disclosed for use in placing cement within the annulus between a casing string and a well bore in which the casing string is suspended such apparatus, including a stage collar connectible as part of the casing string and having a packing element mounted thereon and adapted to be inflated into engagement with the well bore one or more side ports through which cement may be circulated into the annulus above the packer tubular, members or sleeves for opening and closing the ports following inflation of the packing element.
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 July 25, 1990 and granted June 15, 1993. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 25, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 25, 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.