CTOD estimation procedure for clad pipe girth welds subjected to bending load

Abstract This work describes a crack driving force estimation procedure applicable for structural integrity assessments of dissimilar girth welds in clad pipes subjected to high levels of bending load. The purpose of this study is to explore the application of the equivalent stress-strain relationship approach coupled with a weld bevel simplification scheme and the EPRI procedure to evaluate the CTOD for defects located at the weld centerline, including the effects of the weld strength mismatch, weld bevel geometry and the clad layer thickness. Parametric 3D finite element analyses of pipes with circumferential part-through cracks are performed to validate the weld joint simplification and to assess the accuracy of the crack driving forces predictions. Finally, the results show that the estimations using the proposed methodology are in close agreement to those obtained directly from finite element analyses

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