Patents Assigned to Pipeform LLC
  • Interlocked plastic-encased concrete pipe
    Patent number: 5573040
    Abstract: A composite concrete pipe in which both the inner and outer surfaces are plastic. The pipe may be formed of any diameter by forming the inner and outer plastic surfaces from helically wrapped interlocking plastic strips to form the diameters desired.
    Type: Grant
    Filed: February 20, 1996
    Date of Patent: November 12, 1996
    Assignee: Pipeform LLC
    Inventors: Mark W. Schumacher, Raymond L. Sterling