The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 10, 1979
Filed:
Feb. 14, 1977
Fred Byrd, Lebanon, OH (US);
James A Fisher, Middletown, OH (US);
Armco Steel Corporation, Middletown, OH (US);
Abstract
In a line for coating a ferrous base metal strip with a molten coating metal, the line being of the type having a preparation furnace for the strip comprising a direct fired furnace, a controlled atmosphere heating furnace, one or more cooling chambers and a snout leading beneath the surface of the molten coating metal bath, all in sealed relationship to each other, the improvement comprising a method and means for maintaining a non-oxidizing atmosphere at positive pressure within the entire preparation furnace during line stop. To this end, a retractable, refractory lined door means is provided in the conduit between the direct fired furnace and its exhaust fan to seal off the direct fired furnace from its exhaust fan and an air dilution opening in that conduit. Additionally, means are provided to add excess nitrogen flow to the preparation furnace to maintain a positive pressure therein. Thus, during a line stop, the refractory lined door will be shifted from its normal retracted position to its position sealing off the direct fired furnace and the means for adding excess nitrogen will be actuated to maintain a positive pressure within the entire strip preparation furnace of the metallic coating line.