Papers
Plastic Pipes Conference Association # 2012 Barcelona
Andreas Frank, Anita Redhead, Thomas Kratochvilla, Heinz Dragaun, Gerald Pinter
Key words : Polyethylene, pipe, test method, lifetime, slow crack growth For a qualitative characterization of the slow crack growth resistance of polyethylene pipe grades several test methods are available. Especially for modern pipe grades these test methods exceed practical time frames and new acceleration methods for a reliable material ranking are required. The Cyclic Cracked Round Bar (CRB) Test was introduced as an alternative test method with a significant acceleration of testing times even at ambient temperatures. Within the current work studies comparing material ranking by Full Notch Creep Test (FNCT) or Pennsylvania Notch Test (PENT) with Cyclic CRB Tests are summarized. Moreover results of two Round Robin Tests will be discussed. The data show a high reproducibility of the Cyclic CRB Test with a high reliability in terms of an accelerated qualitative material ranking.
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