Plastic Pipes Conference Association # 2023 Lake Buena Vista
Gerald Pinter, Lukas Travnicek, Johannes Wiener, Jan Poduska, Florian Arbeiter, Pavel Hutar
Crack initiation and subsequent crack growth are known to be the key factors which determine the final lifetime of a polymeric pipe. Subsequently, exact knowledge regarding the crack growth behavior is a key issue to guarantee safe operation. Furthermore, novel concepts are needed to satisfy increasing demands, for example with regards to the utilization of recycled materials. The current work shows a summary of the main findings of the scientific work of the last ten years on several approaches on how to control crack growth to optimize the overall potential of polymeric pipe systems.
Within this work, three approaches, which can be used separately, but also conjoined are discussed. Approach number one is the use of a multilayer pipe setup with mechanically similar materials, in order to allow the safe operation of polyethylene pipes containing recycled material even under internal pressure. Approach number two explores the possibilities and also the impact of residual stresses on the final lifetime of pipes. Approach number three shows the potential of using vastly dissimilar materials in order to stop initiated cracks from growing further through the material.
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