Patents by Inventor Darrell R. Lewis

Darrell R. Lewis 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).

  • Drilling mud circulating pit clean out gate valve
    Patent number: 5427353
    Abstract: A drilling mud circulating tank clean out valve is formed by a wedge-shaped valve body having an apertured planar surface secured to the wall of the circulating tank around a cleanout opening adjacent its bottom to form a fluid outlet passageway. A wedge-shaped valve is vertically moveable in the valve body for seating and sealing with a valve seat.
    Type: Grant
    Filed: June 30, 1994
    Date of Patent: June 27, 1995
    Inventor: Darrell R. Lewis