The aging behavior of HDPE pipe bodies and butt-fusion welded joints: effects of thermal oxidative and hydrothermal accelerated aging

We investigate the aging behavior of High-Density Polyethylene (HDPE) pipelines, specifically comparing the Pipe Body (PB) and Butt-Fusion Welded Joint (BFWJ) under thermal oxidative and hydrothermal accelerated aging conditions. Our results indicate that the performance disparity between PB and BFWJ diminishes as aging time increases. We also find that the specimen type affects the quantity of polyethylene fibers, with hydrothermal aging significantly affecting the cohesive force among these fibers in both PB and BFWJ. These findings on differential aging processes of PB and BFWJ contribute to a deeper understanding of HDPE pipeline durability and offer practical recommendations for mitigating degradation risks associated with these disparities. This research underscores the importance of considering specific aging behaviors in the maintenance and reliability assessment of HDPE pipeline systems used in energy transport, industrial, and agricultural applications.