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 U.S. 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.
The first and early day pipe relining was done as a drag in method, with the resin on the inside of the liner. This method is still used today, mainly in pit-to-pit situations. At Infinity Lining PTY LTD, we believe in, as much as possible to have the resin on the outside of the liner. We have found in Sydney, and many parts of Australia, that the native trees are very aggressive, and will creep along the minute gap that having the resin on the inside creates. This is fine with the pit-to-pit, as you can seal the ends with a sealant. In cases where you don’t have a pit at the other end, inverting the liner is far superior, as the resin squeezes into all the cracks and broken joins, stopping the roots ever getting back into the pipe.