Process for manufacturing high-strength bainitic steel rails with excellent rolling-contact fatigue resistance
CA 2116504 C · Owner: Ueda, Masaharu · Inventors: Kageyama, Hideaki; Sugino, Kazuo; Ueda, Masaharu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for manufacturing high-strength bainitic steel rails with an excellent rolling-contact fatigue resistance comprising the steps of hot rolling steel containing 0.15 % to 0.45 % carbon, 0.15 % to 2.00 % silicon 0.30 % to 2.00 %, manganese, 0.50 % to 3.00 % chromium and at least one, element selected from a group of molybdenum nickel, copper, niobium, vanadium, titanium and boron subjecting the, hot-rolled rail to an accelerated cooling from the austenite region to a temperature between 500° to 300° C at which the, accelerated cooling is stopped at a rate of 1° to 10° C per, second, and then further cooling the rail to a lower temperature by natural or controlled cooling. The …
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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 February 25, 1994 and granted June 30, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 25, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 25, 2016.
- 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
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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.