Study on the Applicability of X52 Pipeline Steel with Hydrogen Addition

In hydrogen-containing environments, hydrogen can cause hydrogen damage to metal materials, leading to pipeline and equipment failure. In order to effectively evaluate the safety of hydrogen-blend transportation, an experimental platform has been built to meet the requirements of hydrogen permeation characteristic testing and hydrogen embrittlement degradation testing. Taking the X52 pipeline as an example, a study was conducted on the applicability of hydrogen blending transportation for medium- and low-grade pipeline steel. The results showed that the increase in hydrogen partial pressure would lead to a nonlinear increase in the accumulation of the atomic hydrogen concentration under the surface of the pipe, which would exacerbate hydrogen damage in the pipe and advance the characterization of hydrogen damage characteristics. At the same time, the notch effect will further amplify the characterization of hydrogen loss characteristics. In addition, based on experimental test results, a predictive formula for the relationship between hydrogen damage and atomic hydrogen accumulation in pipes was constructed, laying the foundation for the safety evaluation of hydrogen-doped pipelines. At the micro level, the transformation relationship of the fracture model of pipes under a hydrogen-doped environment was revealed, and it was found that the defect conditions significantly increased the original hydrogen loss degree and influence range of the pipe matrix.