Plastic Pipes Conference Association # 1992 Eindhoven
Ward, Atkinson, Greig, Hansard
A novel die-drawing process has been developed at Leeds University. By incorporating a mandrel, pipes may be expanded hoopwise whilst being drawn axially. Such biaxially-oriented pipes have properties better suited to the transmission of gases and liquids than either isotropic or longitudinally-drawn pipes. In this paper, the biaxially-oriented pipes are characterised in terms of birefringence, density and melting behaviour, and their mechanical strengths, moduli and bursting pressures measured. It is shown that these pipes may be joined by butt fusion and electrofusion socket welding.
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