Hydrogen Impact on Transmission Pipeline Risk: Probabilistic Analysis of Failure Cases
Abstract
Transmission pipelines are the safest and most economical solution for long-distance hydrogen delivery. However, safety and reliability issues, such as hydrogen’s impact on material properties including fracture toughness and fatigue crack growth, could restrict pipeline development. This impact may also increase the risk of several pipeline failure causes, including excavation damage, corrosion, earth movement, material failures, and other hydrogen damage mechanisms. While many quantitative risk assessment (QRA) studies exist for natural gas pipelines, limited work focuses on hydrogen pipelines; the influence of hydrogen must be considered. This work presents a systematic causal model for hydrogen pipeline failures that incorporates multiple failure causes, quantifying hydrogen influence on pipeline failures and analyzing how changes in hydrogen effects or operating conditions impact multiple failure causes. According to the results, (1) hydrogen has a relatively minor impact on corrosion-related failure; (2) hydrogen greatly affects crack damage (the failure probability can increase by over 1000 times); (3) excavation damage is nearly independent of hydrogen’s effects; (4) earth movement damage shows increased susceptibility (the failure probability can increase by over 10 times). The hydrogen effects change the relative susceptibility of pipelines to these failure causes, therefore, to implement tailored safety measures under varying operating conditions.