Cured-in-place pipe

A cured-in-place pipe (CIPP) is a jointless, seamless, pipe-within-a-pipe with the capability to rehabilitate pipes ranging in diameter from six to 96 inches and to negotiate bends. Pipe rehabilitation reduces infiltration and leaks in pipeline systems without digging.

The CIPP Process

A resin-saturated felt tube made of polyester is inverted or pulled into a damaged pipe. Little to no digging is involved in this trenchless process, making for a more environmentally friendly method than traditional "dig and replace" pipe repair methods. Resin/Chemical washout must be controlled for public and environmental safety. To reduce home evacuations and fish kills, an environmental safety plan is required. Next, hot water or steam is used to cure the resin and form a tight-fitting, jointless and corrosion-resistant replacement pipe. During the curing process of any resin system, volatile organic compounds (VOC) and hazardous air pollutants (HAP) are released. Service laterals are restored internally with robotically controlled cutting devices. The rehabilitated pipe is then inspected by closed-circuit television (CCTV). CIPP is considered a trenchless technology.

History

In 1971, Eric Wood implemented the first cured-in-place pipe technology in London, England. He called the CIPP process insit u form, derived from the Latin meaning "form in place." Wood applied for US patent no. 4009063 on January 29, 1975. The patent was granted February 22, 1977 and was commercialized by Insituform Technologies until it entered the public domain on February 22, 1994.

External links

• Information on U.S. Patent no. 4009063:
• Related information on CIPP patents:
• Trenchless Technology:
• How CIPP is installed: