循环载荷作用下聚乙烯管材老化性能及寿命预测

Aging Property and Life Prediction of Polyethylene Pipe Under Cyclic Loading

运行过程中的循环载荷作用会对聚乙烯管材的使用寿命产生影响。为探究聚乙烯(PE)管材在循环载荷影响下的预期寿命,搭建PE管材热氧老化实验平台,对试验PE管施加循环内压载荷,并进行不同老化条件下的加速老化试验。测试老化PE管材的断裂伸长率及氧化诱导期,再分别基于PE管材断裂伸长率及抗氧剂消耗对循环载荷作用下的PE管材使用寿命进行预测。结果表明,在循环载荷作用下,以PE管材断裂伸长率及氧化诱导期为考察指标的预期使用寿命分别为90.04 a和118.51 a,相比基于抗氧剂损耗的寿命预测,基于力学性能的寿命预测结果更偏保守。

Cyclic loading during operation could affect the service life of polyethylene pipe.In order to explore the expected life of polyethylene(PE)pipe under the influence of cyclic load, a thermal oxygen aging experimental platform was built for PE pipe, cyclic internal pressure load was applied to the test of PE pipe, and accelerated aging tests were carried out under different aging conditions.The elongation at break and oxidation induction period of aging PE pipe were measured, and the service life of PE pipe under cyclic loading was predicted based on the elongation at break and antioxidant consumption, respectively.The results show that under the action of cyclic load, the expected service life of PE pipe with elongation at break and oxidation induction period are 90.04 a and 118.51 a, respectively.Comparing with the life prediction based on antioxidant loss, the life prediction based on mechanical properties is more conservative.