Papers
Plastic Pipes Conference Association # 2016 Berlin
Pavel Hutař, Jan Poduška, Jaroslav Kučera, Eva Nezbedová, Andreas Frank, Jiří Sadílek, Gerald Pinter
Residual stresses can significantly influence the lifetime of polymer pipes. Therefore, realistic estimation of residual hoop stress can contribute to accurate lifetime estimations. The previously used “accurate method” is quite time consuming and needs a lot of specimens to be prepared and treated. A simplified method was so far used, based on the assumption of a linear distribution, with the drawback that the results were too conservative. In this paper, a new simplified methodology for determining the residual hoop stress in polyolefin pipes is proposed. This new methodology, based on the assumption of an exponential shape which has been experimentally predefined, provides a more precise estimation of residual hoop stress distribution in the pipe wall. This methodology may be used as well for recalculation of some older results of authors that assumed linear stress distribution in the pipe wall.
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