Lawrence, Potter, Teo
Additional Information - Posters # 1998 Gothenburg
The short term testing of any plastic pipe for its prospective longevity in service is extremely difficult because it requires some accelerated technique which needs to work within or verv close to the normal operatin? strains if extensive creep processes are to be avoided. The problem has now been exacerbated by the progressi\-e improvements made to these products. which has rendered the conventional approach of static type loading method totally impractical. A 'fracture mechanics' neth hod based on cyclic loading that had been pioneered on smaller bore pipes and butt welds is here adapted to large bore (5OOmm diameter upwards) pipe. It is almost axiomatic that any test on pipes of this size \vould be very expensive and so a feasibility study was supported via the ROPAS (EPSRC) grant system to assess both physical and commercial viability. This paper reports on the progress made on that prototype apparatus.
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