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:
Jul. 05, 1977
Filed:
Jun. 13, 1974
Per Harald Collin, Falun, SW;
ASEA Aktiebolag, Vasteras, SW;
Abstract
A furnace for melting solid ferrous pieces such as pig iron and steel scrap, features a combination of electric induction heating and flame heating of the pieces which are charged into the furnace hearth via a charging stack up through which the products of combustion flow from the furnace counter-current to the descending charged pieces moving downwardly through the stack. The flame heating is via burners supplied with hydrocarbon fluid fuel with oxygen proportioned for incomplete combustion, the products of combustion and unburned fuel ascending through the stack and preheating the descending charged pieces. Air is supplied to the stack to complete the combustion of the previously unburned fuel in and around the descending pieces, this being done at a level where the descending pieces have not yet reached temperatures sufficient to cause excessive oxidation of the pieces. Other details providing for effective utilization of these principles, are included in the disclosure.