Silane PEX (SPEX) liners - a commercial reality in the water industry

摘要

The water industry is being judged on the way that it maintains its underground assets to deliver a sufficient quantity of good quality water at an adequate pressure. In practice this involves rehabilitating the old cast iron mains. The use of fully structural PE linings is expensive. Therefore the industry uses less expensive thin wall PE interactive linings which share the internal pressure loads with the host pipe. PE has limitations in long term creep and necking when bridging voids, gaps and internal protrusions. This paper describes a range of Silane PEX (SPEX) liners that have been developed specifically for interactive liners. The liner can be installed as a loose fitting PE liner, then crosslinked insitu using the flowing drinking water to produce a fully crosslinked structure having superior long term creep, yield strain and crack resistance than PE. This type of PEX liner can also be butt fusion welded and extruded using standard PE equipment.