Patents by Inventor Noel Lutgen

Noel Lutgen has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Process for producing steel having a low content of nitrogen in a ladle furnace
    Patent number: 4990183
    Abstract: The present invention relates to a process for producing steel in a ladle furnace in which the molten steel is stirred by injection of an inert gas in the lower part of the furnace. According to the invention, the stirring of the bath of steel is effected by the injection of gaseous argon so as to distribute in a homogeneous manner the additives added and the metal temperature in the course of the treatment, while there is simultaneously injected liquid argon above the surface of the bath in the region of intumescence. In this way, substantially any increase in the concentration of nitrogen of the bath of steel in the course of the treatment is avoided. In some cases, and in particular when wires of the type filled with silico-calcium are employed, a reduction in the concentration of nitrogen in the bath of steel is found.
    Type: Grant
    Filed: August 24, 1989
    Date of Patent: February 5, 1991
    Assignees: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude, Liquid Air Corporation
    Inventors: Sara H. Anderson, Noel Lutgen, Jean Foulard