High Performance Fabric In Old Piping: Quick, Durable Restoration Of Operational Safety

By Andreas Hüttemann, Qualified Engineer Director, R&D/Quality Management, Karl Weiss Technologies and Brian Mattson, Business Development Manager, GTI | December 2009 Vol. 64 No. 12
Fig. 6 Woven fabric reversion of pit three toward pit one with a length of 994 feet.

During the World Gas Conference in Copenhagen, Denmark in June 1997, representatives of U.S. gas utilities asked members of Karl Weiss Technologies, Berlin, Germany, whether they could develop a special fabric hose rehabilitation system for gas services featuring 90 decree elbows.

Karl Weiss agreed to start development work.

In 1998, successful demonstrations convinced gas utilities of the professional performance and efficiency of the technology. On Feb. 10, 1999, Karl Weiss established Starline Trenchless Technology, LLC to promote and commercialize trenchless technologies in the U.S. The Gas Research Institute (precursor to today’s Gas Technology Institute) joined the newly formed company as a strategic partner.

Subsequent development of the technology has diversified the applications of starline technology into pressure water pipe as well. Now, aging gas and water mains are returned to their original strength through the use of flexible, seamless, circular-woven fabric liners installed in the pipes with a special inversion process, without the need for long trenches. This relining process, unlike open-trench gas and water-line replacement, enables utilities to minimize traffic control, excavation, and pavement and landscape restoration - tasks that can account for up to 70 percent of the cost of gas and water-line rehabilitation. Unlike straight or rigid liners, cured-in-place liners can be installed through bends, fully open fittings and where there may be variations in internal pipe diameters.

Case study
In Germany’s capital city Berlin, drinking water is distributed through a 4,900-mile-long pipe network and pumped to 262,000 house connections, 62,000 hydrants and 90,000 valves. Nevertheless, even during consequential maintenance, damage to pipes cannot be totally prevented. When repairing damage to pipes, Berlin Water Works can implement individually suited solutions as was the case recently with the quick and durable restoration of a 20-inch cast iron drinking water pipe by means of woven fabric liner.