Plastic Pipes Conference Association # 1995 Edinburgh
Kitao, Hiarse, Nishimura, Inouge, Ishikawa, Otani, Miyasa, Kato
In this paper, the behavior of rapid crack propagation in gaspressurized polyethylene pipes was analyzed using the method in which two characteristic curves, i.e., the crack velocity and the gas decompression velocity, were compared. The crack velocity of 216mm outer diameter SDR13.5 medium density polyethylene pipes at -1O0Cwas evaluated by the Small Scale Steady State(S4) test. The full scale behavior of rapid crack propagation was simulated by 3m length S4 tests without internal gas-flow baffles and external containment cages. The behavior of crack propagation and arrest were well explained by this analysis method. Finally, drop weight tear test(DWTT), based on transition criteria in which arrest temperature is evaluated, was examined.
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