Papers # 2014 Chicago
Polyethylene pipe is being routinely used for the close fit lining of large diameter water trunk mains, with the twin objectives of improving water quality and reducing losses due to leakage. Trunk mains serve large urban areas and by definition are large diameter pipes; examples of real lining schemes in the past 12 months include sizes to 55” (1400mm). As close fit lining technology is being scaled upwards in size, the question of fittings technology becomes important, both to achieve cost effective as much as reliable solutions. We set out in this paper the results of work to develop a system for making connections to trunk mains that have been close fit lined with polyethylene pipe so that air valve discharge points and water drains can be installed at a reduced cost. The results of early testing are presented to examine the types of failure modes to be anticipated and addressed in design to ensure reliable operation.