Method for producing galvanized tubing
CA 2028004 C · Owner: Allied Tube & Conduit Corporation · Inventors: Patel, Vijay B.; Maitra, Kalyan K.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An improved method of manufacturing galvanized steel tubing from steel strip having at least one galvanized surface, which surface becomes the exterior surface of the tubing is provided. In the method of the invention after the steel strip is roll-formed and welded to complete the tubing and the welded seam is scarfed to remove irregularities, a quantity of an acid solution is applied to substantially only the scarfed area to react with oxidized metal, and the rinsed, leaving the non-scarfed galvanized exterior surface intact. The tubing is then heated to a temperature sufficient to cause the galvanized coating of the exterior surface to begin to flow and the tubing is regalvanized to …
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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 October 18, 1990 and granted March 16, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 18, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 18, 2012.
- 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.