December 28, 2011Innovative Sewerage Technologies (I.S.T.), Germany, a leading producer of sewer rehabilitation products, has launched the world’s first polyurethane-based cure-in-place pipe (CIPP) repair system for the trenchless technology market.
With a working time of up to 24 hours between liner impregnation and installation, plus snap cure capabilities, the solution is a major breakthrough in CIPP system technology, offering utility companies and contractors significant time and cost savings in the repair of broken or fractured sewer pipes, according to an I.S.T. press release.
The I.S.T solution comprises a traditional needle-felt liner and a polyurethane resin called VITROX — a unique isocyanate product developed by Huntsman Polyurethanes, one of the world’s major chemical companies.
VITROX resin is a two-component system with an exceptionally long pot life. Its increased working time window has the potential to revolutionize CIPP working practices. Traditionally companies repairing sewer networks have had to rely on epoxy resins with a relatively short pot life. This meant impregnating hose liners on site, prior to insertion, often under unfavorable conditions.
Using VITROX, far more time is available between resin application and installation. As a result, liners can be prepared off site, the day before application, at a suitable indoor location. This reduces the risk of mixing faults, which can occur on outdoor sites because of inclement weather conditions. It also means actual repair work can start onsite as soon as the team arrives each day.
A further benefit is the speed at which VITROX resins can cure. With a unique snap cure mechanism VITROX resins will harden on demand when the system reaches an elevated, predefined temperature. For the CIPP market, this has been set at just two hours using water-curing techniques (greater than 75 C) and less than one hour using steam methods. VITROX resin can be used with standard CIPP equipment and after curing is resistant to temperatures of up to 120 C.
VITROX resin has been tested extensively in the field by I.S.T and is currently undergoing German national certification from Deutsches Institut für Bautechnik (DIBt) Berlin — a third party institute.