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:
Aug. 22, 1995
Filed:
May. 04, 1994
Giovanni Coassin, Pordenone, IT;
Corrado De Cecco, Ragogna, IT;
Gianni Gensini, S. Stefano di Buia, IT;
Sergio Gerussi, Pagnacco, IT;
Danieli & C. Officine Meccaniche SpA, Buttrio, IT;
Abstract
Electric arc furnace with alternative sources of energy, which functions with direct current or alternating current and comprises at least one lance (12) to inject pure or combined oxygen above the bath (16) and a plurality of tuyeres (13) positioned in the hearth of the furnace (10) to inject oxygen below the bath, the tuyeres (13) being cooled by a peripheral movement of a cooling mixture consisting of at least one gas having a high cooling power (methane, butane, inert gases, etc.) and of at least one diluting gas (nitrogen, carbon dioxide), pipes (15) being included to introduce additives and powdered coal, post-combustion burners (28) possibly being comprised, the tuyeres (13) including an oxygen delivery pipe (18) having a diameter greater than 8 mm., the oxygen pressure being capable of being modulated according to the working steps, there being a constant minimum pressure of delivery. Melting operating method associated with such an electric furnace, wherein the charging operation with each single charge (skip) is divided into defined periods, with which are associated a pressure of delivery of oxygen through the tuyeres (13) and a percentage of gas having a high cooling power and proportioned to the rate of flow of the oxygen, there being a minimum pressure of delivery of oxygen in each moment of the working of the furnace (10).