Patents by Inventor Apparao Duvvuri

Apparao Duvvuri 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: 5638893
    Abstract: The parting agent spray system is used with a roll casting machine to reduce the parting problems associated with releasing the casting-strip from the rolls. The parting system comprises a bank of self-cleaning spray nozzles for each of the upper roll and the lower roll of the caster. Each bank of nozzles is enclosed in its own individual housing which terminates proximal to the surface of the roll, and is movably located on a track. The housing is utilized to contain any excess graphite spray and prevent it from escaping from the area around the roll caster and contaminating the surrounding environment. The nozzles are grouped into zones, each zone connected to a parting agent solution source via an influent parting agent solution line, and connected to an air source via an air supply line for controlling the flow of the parting agent solution through each of the nozzles and atomizing the same, thus allowing the nozzles in each zone to be independently manipulated.
    Type: Grant
    Filed: October 7, 1993
    Date of Patent: June 17, 1997
    Assignee: FATA Hunter, Inc.
    Inventors: Subbiah Sankaran, Apparao Duvvuri
  • Patent number: 5584336
    Abstract: A method of operation of a twin roll casting apparatus to produce thin gauge sheet metal at high-production rates. The method includes simultaneously adjusting various operating parameters, such as the roll speed, tip position, roll gap, molten metal input temperature and exit strip tension. In an iterative fashion, the strip gauge is reduced in steps while increasing the speed of the rolls and pulling the tip back out of the roll bite. In conjunction with the aforementioned adjustments, the temperature of the molten metal input to the feed tip is gradually reduced to ensure proper solidification at higher speeds. A set of pinch rolls closes on the exit strip at a certain gauge thickness to apply a drag to the strip in order to ensure proper coil wind-up tension.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: December 17, 1996
    Assignees: Norandal, USA, Fata European Group S.r.l., Hunter Engineering Company, Inc.
    Inventors: Christopher A. Romanowski, Apparao Duvvuri, William E. Carey, William M. Marrison
  • Patent number: 5518064
    Abstract: A method of operation of a twin roll casting apparatus to produce thin gauge sheet metal at high-production rates. The method includes simultaneously adjusting various operating parameters, such as the roll speed, tip position, roll gap, molten metal input temperature and exit strip tension. In an iterative fashion, the strip gauge is reduced in steps while increasing the speed of the rolls and pulling the tip back out of the roll bite. In conjunction with the aforementioned adjustments, the temperature of the molten metal input to the feed tip is gradually reduced to ensure proper solidification at higher speeds. A set of pinch rolls closes on the exit strip at a certain gauge thickness to apply a drag to the strip in order to ensure proper coil wind-up tension.
    Type: Grant
    Filed: May 16, 1994
    Date of Patent: May 21, 1996
    Assignees: Norandal, USA, Fata European Group S.r.l., Hunter Engineering Company, Inc.
    Inventors: Christopher A. Romanowski, Apparao Duvvuri, William E. Carey, William M. Marrison