Forge welding method
CA 2492745 C · Owner: Halmrast, Bjorn · Inventors: Rabben, Kjell Magne; Halmrast, Bjorn; Den Boer, Johannis Josephus
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for forge welding tubulars such that formation of upsets in the welding zone is minimized comprises shaping the tubular ends that are to be welded together into an inwardly sloping configuration such that when the tubular ends are heated during the forge welding process the heated tubular ends deform as a result of thermal expansion into a substantially longitudinally oriented cylindrical shape.
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, 2003 and granted January 3, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 17, 2023.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 17, 2025.
- 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.