Patents by Inventor James R. Tietema

James R. Tietema 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).

  • Blow-out preventor test tool
    Patent number: 4881598
    Abstract: Apparatus and methods are provided for testing a blow-out preventor system of a well, which blow-out preventor system is designed to close upon both a smaller drill pipe string and a larger drill pipe string. The apparatus includes a first elongated cylindrical testing mandrel having an outside diameter substantially equal to an outside diameter of the smaller drill pipe string, and a second elongated cylindrical testing mandrel having an outside diameter substantially equal to an outside diameter of the larger drill pipe string. The first testing mandrel is telescopingly received within the second testing mandrel.
    Type: Grant
    Filed: November 3, 1988
    Date of Patent: November 21, 1989
    Assignee: Conoco Inc.
    Inventors: Michael P. Stockinger, James R. Tietema, Lee S. Bass