Cured-in-place pipe: Trenchless trends

A variety of CIPP products are enabling the rehabilitation, rather than excavation and replacement, of underground pipe for wastewater and drinking water.

It goes by several aliases: Trenchless technology. In-situ pipe repair. Pipe-within-a-pipe. By any name, the underground construction rehabilitation market is a boon to motorists, who suffer fewer delays and take fewer detours. And it’s also a blessing for the construction crews that do the work. They call it “no dig” because that slight exaggeration captures its chief benefit: the installation, replacement or repair of underground utility pipe with minimum excavation and surface disruption. In the U.S., trenchless technology continues an upward growth trend. It has captured nearly half of the $3.4 billion market for sewer line rehabilitation and about an eighth (12.9 percent) of the $1.5 billion spent on repairing potable water pipes, according to the 15th Annual Municipal Infrastructure Survey conducted by Underground Construction (Oildom Publishing Co., Houston, Texas).

Cured-in-place pipe (CIPP) has been a growing subset of trenchless technology since its 1971 debut and is now a substantial market for composite materials (see Table 1, at left). Bill Moore, product leader for CIPP at resin producer AOC LLC (Collierville, Tenn.), notes that CIPP might be AOC’s biggest market. “While a lot of markets have diminished in the past few years, CIPP has grown,” he says.

CIPP typically consists of a resin-impregnated felt or fiber sleeve. With its resin in an uncured state, it forms a flexible, conformable tube that can be inserted into a damaged pipe. Some sleeves are manufactured inside out and are inverted as they are pushed into the existing pipe via air or water pressure…

Read the full article: