Drilling fluids, drilling fluids additives and methods useful for limiting tar sands accretion on metal surfaces
CA 2437522 C · Owner: Horton, David P. · Inventors: Horton, David P.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Fluids and methods useful in oil well drilling operations are described. The fluids comprise standard viscosifying and fluid loss control additives along with phosphonates or phosphate esters of organic ligands. The addition of the phosphonates or phosphate esters at effective concentrations limits the adherence of heavy oil and heavy oil laden drill cuttings to drill pipe strings and well bore casings.
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 15, 2003 and granted February 15, 2011. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 15, 2023.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 15, 2025.
- 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.