Forge welding of heavy duty tubulars
CA 2492479 A1 · Owner: Cole, Anthony Thomas · Inventors: Zijsling, Djurre Hans; Cole, Anthony Thomas; 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 of joining heavy duty oilfield well, or other tubulars comprises , joining the tubulars by forge welding and flushing a reducing flushing gas around the heated tubular ends during at least part of the forge welding operation such that oxides are removed from the forge welded tubular ends and the amount of oxide inclusions and irregularities between the forge welded tubular ends is limited. The tubular ends may have a teethed or non-planar shape to inhibit any abrupt variations of the wall strength in the welding area and/or to reduce shear forces to the forge weld when the tubulars are twisted and/or radially expanded.
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. No grant is recorded for it in Canada; had it been granted, its 20-year term would have 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.