Patents by Inventor Shunji Nishi

Shunji Nishi 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).

  • Threaded joint for oil-well pipe
    Patent number: 4830411
    Abstract: A threaded joint for oil-well pipe comprises a box having an internal thread, a pin having an external thread, a metal-to-metal sealing contact provided at the unthreaded tips of the box and pin, and a film of grease applied on the surface of the internal and external threads. The cross-sectional area of a void containing the screw axis left between the meshed internal and external threads is at least 0.6 mm.sup.2 per pitch.
    Type: Grant
    Filed: February 12, 1988
    Date of Patent: May 16, 1989
    Assignee: Nippon Steel Corporation
    Inventors: Eiji Tsuru, Shunji Nishi, Masao Ogasawara