Patents by Inventor Nelson H. Kehl

Nelson H. Kehl 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).

  • Patent number: 4667385
    Abstract: For a molten metal stirring lance a steel tubular member is coated interiorly with wax, for instance, and a refractory material plug is cast in the member. The plug extends from one end of the member and leaves a clear space near the other end. Melting the wax out leaves a thin gas passageway gap around the plug. The end having the clear space is capped and connected to a gas feed pipe which is surrounded by a stiffener member. The latter member is convered with a refractory material protective sheath. The refractory material in the tubular member erodes or ablates by a small amount during each use in molten metal to keep the gas discharge gap clear.
    Type: Grant
    Filed: August 23, 1985
    Date of Patent: May 26, 1987
    Assignee: Midwest Instrument Co., Inc.
    Inventors: James W. Colzani, Nelson H. Kehl