Patents by Inventor Mark D. Vanderwoude

Mark D. Vanderwoude 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).

  • Plastic pipe extrusion
    Patent number: 5028376
    Abstract: In the extrusion of plastic pipe wherein the pipe is in a self supporting but semi-molten state on exiting a die orifice, the inner surface of the extrudate is cooled by a device which applies a suction for establishing flow of a cooling fluid which contacts the inner surface of the extrudate. In a further embodiment the flow of cooling fluid established for cooling the extrudate additionally cools a cavity within a mandrel of the die orifice.
    Type: Grant
    Filed: July 24, 1989
    Date of Patent: July 2, 1991
    Assignee: Phillips Petroleum Company
    Inventor: Mark D. Vanderwoude