Patents by Inventor John P. Petreanu

John P. Petreanu 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: 5292375
    Abstract: Lead in coatings on structures can be removed, without creating hazardous waste, by a flame spray process which utilizes a glass composition having high lead solubility, resistance to devitrification, and an expansion coefficient which is substantially different from that of the metal structure. The process comprises flame spraying particles of a glass powder composition onto the lead based coating to form a layer of glass material, permitting the glass layer to cool sufficiently so that it spalls, thereby forming fragments of the glass layer which readily separate from the structure, collecting the glass fragments, and repeating these steps until any organic material in the coating has been pyrolized and removed as part of the fragments, substantially all red lead present in the coating has been reduced to yellow lead, and all of the lead which was in the lead based coating has been removed from the structure by being incorporated into the glass layers.
    Type: Grant
    Filed: June 7, 1993
    Date of Patent: March 8, 1994
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Ashok Kumar, John P. Petreanu