Process and apparatus for vacuum degassing molten steel
CA 2104910 C · Owner: Fukuda, Kazuhisa · Inventors: Isono, Takahiro; Yamada, Atsumi; Gofuku, Hiroki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Molten steel is efficiently vacuum treated in a vacuum treatment vessel provided with a tap blow lance capable of injecting an oxygen gas and a fuel gas at desired flow rates respectively, onto molten steel on the top of the vacuum treatment vessel in a freely vertically movable manner by setting the lower end of the top blow lance to a level of not more than 2 m from the surface of molten steel bath and injecting only an oxygen gas onto the molten steel and thereafter setting the lower end of the top blow lance to a level of 1.0 m or more from the surface of molten steel bath and injecting both of oxygen gas and a fuel gas from the top blow lance onto the molten steel. The process 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 August 26, 1993 and granted November 16, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 26, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 26, 2015.
- 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.