Plastic Pipes Conference Association # 2006 Washington DC
Christodoulou, Wilson, Hunter, Bowman
Polyethylene (PE) based and metallic pipe systems have been assessed for their ability to stop petrol migrating through the pipe wall, fitting or joint and into water contained within the pipe. A quantitative test was devised that is capable of distinguishing between the different pipe systems. Plain PE pipe is relatively translucent to petrol, but the inclusion of a layer of welded aluminium (Al) in the middle of the wall of a PE pipe stops the migration of petrol. But to create an effective pipe network that stops petrol migration, the use of metallic fittings is required, as the currently available plastics fittings that were tested all allowed significant amounts of petrol to migrate through into the system. Iron based pipe systems show both significant migration of petrol into the pipe (we believe via ‘O’ ring seals), and significant contamination believed to arise from the lining used to stop the corrosion of these iron based pipe systems. Iron based pipe systems were the worst performing, except for plain PE pipes. The above observations are significant for pipe systems to carry potable water and to be installed in ground that may contain contamination arising from a previous industrial use.
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