Wood, Richards, Street, Muckle, Bowman
# 2006 Washington DC
For the movement of fuel gas and water, plastics pipes are dominant in many markets, and this success has been based on single material solid wall pipes. There are now an expanding number of multi-layered plastics pipes, and described here for the first time is the performance of the second-generation of skinned pipe from Uponor Ltd. The skinned pipes described here consist of a pressure rated core polyethylene (PE) pipe, and a sacrificial skin made from polypropylene (PP). The new pipe retains all the positive values of the first generation of these pipes, but has enhanced resistance to fracture at low temperatures. The authors report on the pipe structure, provide data on skin adhesion, supply information on the electrofusion (EF) joint performance when EF fittings are jointed to this pipe, and give data on the raised fracture resistance of the 2nd generation pipes. New families, and new generations, of multi-layered plastics pipes are being developed, as such pipes can give major benefits to utility companies via enhanced tolerance to pipe laying, improved productivity of EF jointing, and raised quality of EF joint performance.
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