In the fitness for service assessment of a welded component with crack like defect, the current industry practices treat the welding residual stress in the same way as the applied operating stress in calculating the crack driving force. Although a growing crack should release the welding residual stress, the same initial residual stress is used in calculating the stress intensity factor solution regardless of the crack depth. Such procedures should result in too conservative solutions, since the crack extension effect on welding residual stress release is ignored in the crack driving force calculation. The present paper discusses the current state of the industry code and standard procedures for welded component defect assessment with a practical example problem solution, along with detailed discussions on the effects of crack growth on the welding residual stress. The objective of the paper is to motivate the industry to improve the code and standard procedures for the weld defect assessment. Also it presents a comparison of crack-like defect assessment results between the current industry procedure and one of newly proposed crack driving force calculation procedures for a crack growing in welding residual stress field, considering the welding residual stress release effects of growing crack. Recommendations for improving the industry code and standard procedures for the weld area defect assessment are provided based the investigation.

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