Yuji Higuchi, Rei Hyuga, Kazushi Yamada, Hiroyuki Nishimura
Papers # 2016 Berlin
Recently, thermoplastic-based composite pipes have been developed in order to satisfy the higher requirements for gas and water distribution. Although the stress rupture test is now the major test method used to evaluate the long-term performance of these pipes, developing a new, convenient test method making it possible to safely and easily evaluate the properties of composite pipes is needed. Therefore, a simpler method such as the tensile fatigue test with ring shape specimens was studied as a method for evaluating long-term performance. Although it depends on layer components, it is suggested that compared to the stress rupture test, the ring tensile fatigue test is better able to speedily evaluate long-term performance for some composite pipes. This method also has the advantage of being applicable to a pipe with scatter layers when it was cut from rectangle direction; the notched test method cannot be applied because of the impossibility of inserting a razor-notch. It is suggested that this new test method could possibly replace the conventional creep and fatigue testing method for some composite pipes.