Branch boreholes
CA 2226970 C · Owner: Smith International, Inc. · Inventors: Bruce, Ronald James; Mcgarian, Bruce
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of forming and lining a branch borehole comprises installing a packer in a main borehole, installing a whipstock on the packer milling a window in , the main borehole casing using the whipstock recovering the whipstock, and , then installing a deflector (20) to deflect a lining into the lateral. The external diameter (D) of the deflector is less than the internal diameter of the casing of the main borehole so as to permit subsequent milling away of cement and surplus lining material using a washover tool or thin walled mill. The preferred deflector includes a relatively steep deflector face (21) at the upper end of the deflector and a relatively shallow deflector face (22) …
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 17, 1996 and granted October 7, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 17, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 17, 2018.
- 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.