Research on residual stress and hydrogen diffusion of X80 pipeline welded joint

Hydrogen enrichment induced by pipeline welding residual stress is a key issue affecting the safe service of hydrogen pipelines. In order to explore influence on diffusion and effect heat treatment, an X80 model with six-layer girth weld was established using ABAQUS software, coupling analysis temperature field, carried out. The distribution in area local inclusion analyzed, relationship between hydrostatic pipeline, direction shape were explored, post-weld treatment studied. curve similar concentration curve, can be considered main driving force for pipeline. As angle inclusions increases, flux will gradually decrease. more slender inclusions, stronger ability parallel or 45° weaker perpendicular inclusions. occurs boundaries before after internal hard higher than that soft Post-weld significantly reduce stress, thereby reducing concentration.