Patent · US Expired

Polymeric pipe deformer and method for relining existing pipelines

US6058978A · kind A · utility

29Cited by
41References
21Claims
0Family size

Inventors

Key dates

Filing dateJul 17, 1996
Grant dateMay 9, 2000
Priority date
Expiry dateJul 17, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S138/07
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A method and apparatus for relining, repairing or reconstructing existing infrastructure pipeline systems that are new, structurally deficient or experiencing an excessive amount of exfiltration or infiltration, or converting new or damaged pipelines into dual-containment pipelines. A plurality of stock, high density polyethylene lining pipes having a cylindrical cross-section with a diameter up to 36 inches and lengths of 40-50 feet are joined together to a job specific length. The lining pipe is then heated to its flex temperature and gradually deformed to a reduced diameter. At the job site, the deformed lining pipe is inserted into the existing pipe and a controlled, pressurized environment is created therein for a period of time dependent on the pipe's length. Pressurized steam is first inserted to provide heat and internal pressure to expand the pipe. Then, compressed air is inserted to cool the pipe while maintaining the internal pressure to complete the expansion and set the pipe. When converting to dual-containment pipelines, the deformed pipe will have a plurality of spacers attached thereon such that the existing and deformed pipes are axially aligned and have an annular…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.