Drilling tool
CA 1306458 C · Owner: Smith International (North Sea) Limited · Inventors: Lau, Werner
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A tool is intended for use in an oil or gas well to retrieve a drilling or production string from the well particularly in a situation where the casing or formation has collapsed, thus gripping the drilling or production string. The tool has a driven member which presents, at its lower end, a self-tapping thread such as a counterclockwise self-tapping thread. The tool includes a ratcheting arrangement which can drive the driven member in a counter-clockwise direction when the tool is lowered relative to the driven member. The tool can be repeatedly raised and lowered thus enabling the selftapping thread to be engaged with the top of the drilling or production string.
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
- Granted August 18, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended August 18, 2009.
- 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.