Drill bit with protection member
CA 2546316 C · Owner: Shell Canada Limited · Inventors: Savignat, Jean-Michel Claude Gaston; Zijsling, Djurre Hans
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method is provided for removing a body of selected material from the interior of a casing extending into a borehole formed in an earth formation. The method comprises lowering a drill bit for further drilling of the borehole, into the casing, the drill bit having a longitudinal axis of rotation during operation, the drill bit comprising rock cutting means at , least one protection member for protecting the inner surface of the casing from contact with the rock cutting means each protection member being adapted , to remove said selected material from the interior of the casing and being radially movable towards the inner surface of the casing and control means , for applying a …
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 November 26, 2004 and granted July 31, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 26, 2024.
- Certificates of supplementary protection extend only drug patents, and it isn't classified as one.
- 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.