Patents by Inventor Kai Ravnborg

Kai Ravnborg 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).

  • Method of alloying aluminum and calcium into lead
    Patent number: 4808376
    Abstract: A method of alloying powdered aluminum into lead to form lead-calcium-aluminum alloys with relatively high recoveries and low standard deviations of recoveries. The method comprises melting lead, heating the lead, injecting simultaneously calcium-containing granules and aluminum powder into the lead under the surface. The alloying material preferably has a total calcuim content of between about 65% and 80% by weight and a total aluminum content of between about 35% and 20%. The material is preferably injected into an injection bell to hold the alloying material under the surface of the lead.
    Type: Grant
    Filed: August 10, 1987
    Date of Patent: February 28, 1989
    Assignee: The Doe Run Company
    Inventors: Anthony W. Worcester, Kai Ravnborg, Carlos E. Aguirre