Method and apparatus for locating a drill bit when drilling out cementing equipment from a wellbore
CA 2239645 C · Owner: Top-Co Gp Inc. As General Partner For Top-Co Lp (A Limited Partnership) · Inventors: Ryll, Robert Lawrence
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for locating a drill bit when drilling out cementing equipment from a casing of a wellbore. A first step involves placing in the casing of the wellbore at the time of placing cementing equipment, at least one coloured marker member. A second step involves monitoring cuttings during drilling for traces of colour. Penetration of a drill bit into the cementing equipment is indicated by coloured cuttings from the at least one coloured marker member.
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 5, 1998 and granted April 8, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 5, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 5, 2020.
- 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.