Experimental study on aging performance of polyethylene gas pipelines

Abstract

Currently, there is a lack of adequate standards for evaluating the integrity inspection cycle of polyethylene (PE) gas pipelines. In this study, a series of photo-oxidation accelerated-aging experimental tests for PE80 gas pipe samples were performed. The attenuation laws of several critical performance parameters, such as micro-morphology, tensile strength, and thermal stability tests, were established. These parameters were determined at different aging times. A novel comprehensive performance evaluation method for pipeline integrity was developed using the analytic hierarchy process, and a reasonable inspection period for pipeline integrity was identified. The results showed that the samples experienced two stages of aging: rapid aging stage and aging platform stage. During the rapid aging stage, the comprehensive evaluation index for the aging performance decreased rapidly. However, the comprehensive evaluation index for the aging performance remained almost unchanged during the aging platform stage.