A method of forming a bore
CA 2858236 C · Owner: Technology Ventures International Limited · Inventors: Burge, Philip M.; Hewson, James A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of forming a supported subterranean well bore in which in one disclosed embodiment, a first drill bit is mounted on a first string of casing tubulars via a steerable tool and the drill bit is used to form a first bore. Upon reaching the required depth the casing string is cemented in place to support the formed bore and a second drill bit is mounted on a second casing string and is inserted into the first casing string. The second drill bit is used to drill through the wall of the first casing string and proceed to form a second deeper bore. Once the second drill bit has reached the required depth the second casing string is cemented in place to support the second bore.
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 May 27, 2004 and granted December 5, 2017. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 27, 2024.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 27, 2026.
- 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.