Plastic Pipes Conference Association # 1995 Edinburgh
Headford
A novel polyethylene stub flange adaptor is described which allows size-for-size connection, in terms of the respective bores, to iron pipes or fittings. The end load performance of this product is significantly superior to that achieved with conventional polyethylene flanges, especially at large pipe diameters, and the paper attempts to explain the reasons for this. Additionally there is evidence that the sealing performance of mechanical pipeline joints made using this component may be inherently superior, especially where pressure fluctuations occur. Referring to experimental evidence obtained with a slightly different embodiment of the device, it is argued that this potential for enhanced sealing could be fully realised in the case of the hoopreinforced flange by attention to design factors that would minimise stress relaxation effects within the clamped polyethylene shoulders.
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