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. 14, 1987
Filed:
Nov. 19, 1985
Guy Savard, Westmount, CA;
Robert Lee, Montreal, CA;
Canadian Liquid Air Ltd./Air Liquide Canada Ltee, Montreal, CA;
Abstract
Molten steel, normally exposed to an atmosphere of air, is protected against impurities by placing a gas containing a major amount of carbon dioxide gas in such quantities and in such proximity to the surface to cause dissociation of the carbon dioxide at a rate which provides a gas barrier or shroud isolating the steel from the surrounding atmosphere. This method may be applied to protecting certain molten steels being transferred from a ladle to a mold, or from a ladle to a tundish and from the tundish to a mold in continuous casting. In a method where a number of shrouding operations are carried out in series, gas under pressure is bled, in increments, from a storage vessel containing a body of liquid carbon dioxide in an overlying ullage space containing vapor. Each increment is ultimately expanded and dispersed at ambient temperature to form the shroud. As each increment of vapor is removed from the vessel, it is replace by withdrawing liquid carbon dioxide, vaporizing it and returning it to the ullage space.