Patents by Inventor Peter Spence Clough

Peter Spence Clough 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).

  • Temporarily blocking the bore of a pipe through which a fluid flows with a foamed plug removed by dissolving
    Patent number: 5687771
    Abstract: A kit is provided for temporarily blocking the bore of a pipe through which a fluid flows, the kit comprising an expansible flexible bag seal which is inserted through a hole provided in the wall of the pipe and an apparatus for injecting into the bag seal a quantity of a material adapted to expand in situ in the bag seal and inflate the bag seal to seal against the inside of the pipe. The pipe may be a gas main and the material may be an expandable synthetic resin foam. The bag seal is removed by injecting thereinto a substance capable of dissolving the foam so that the bag seal can be at least partially deflated.
    Type: Grant
    Filed: November 30, 1994
    Date of Patent: November 18, 1997
    Assignee: British Gas plc
    Inventor: Peter Spence Clough