Improved heat treatment of grinding rod
CA 2232024 C · Owner: Molycop Steel Inc. · Inventors: Pugh, Robert William
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for heat treating a steel bar to produce a grinding rod having a softer core of at least 99% pearlite and having a hardness of less than 45 Rockwell C an outer shell of martensite having a hardness of at least 50 Rockwell C and softer end portions having a hardness of less than 35 Rockwell C where the softer end portions each having an engineered heat treated length less than 15 cm comprises repeating a formed steel bar to above its austenitising temperature transferring with minimal cooling the repeated bar to an open tubular quench vessel while securing the bar in the vessel to minimize bar warping in the vessel during quenching introducing quench water into an inlet end of 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 March 13, 1998 and granted September 17, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 13, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 13, 2020.
- 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.