One trip milling system
CA 2803822 C · Owner: Smith International, Inc. · Inventors: Dawson, Alexander William; Robin, Andrew Macdonald; Nairn, Gregory S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The mill assembly and whipstock assembly include a mill having a tapered end which engages and has an angle complementary to a ramp of the whipstock assembly. The ramp includes a plurality of surfaces having different angles whereby the rate of deflection of the mill by the whipstock varies as the mill is lowered into the borehole. In particular the ramp of the whipstock includes two surfaces having steep angles one steep angled surface causing the mill to punch through the wall of the casing and the second steep angle surface moving the center of the mill across the wall of the casing.
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 March 25, 1997 and granted June 10, 2014. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 25, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 25, 2019.
- 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.