Patents Assigned to Sentry Piping Systems, Inc.
  • Patent number: 4818314
    Abstract: A method for lining a high pressure pipeline with a tubular plastic liner. After depressurizing, purging and cleaning the pipeline is broken into discrete sections each of which is to receive a liner segment. The sections are reamed to remove obstructions which might damage the liner and a close-fitting liner segment is drawn into each section. Each liner segment is fixed at opposed ends of respective pipeline sections to prevent longitudinal movement of the segments. Bleeder holes are provided through the pipeline walls at opposed ends of each pipeline section. After the pipeline sections are reconnected to reform the pipeline, a relatively warm, pressurized fluid is pumped through the pipeline to radially expand each liner segment against the inner walls of the pipeline, thus evacuating the spaces between liner segments and pipeline sections by forcing air, water and other impurities through the bleeder holes.
    Type: Grant
    Filed: September 12, 1986
    Date of Patent: April 4, 1989
    Assignee: Sentry Piping Systems, Inc.
    Inventors: Perry N. Brittain, John D. Kirkpatrick