Effects of Similar Metal Weld on Residual Stress in Dissimilar Metal Weld According to Safe End Length

동종금속용접이 이종금속용접부 잔류응력에 미치는 영향 평가 시 안전단 길이에 따른 효과

  • Published : 2009.07.01


Nozzle in nuclear power plant is connected to pipe using safe end. Dissimilar metal weld between nozzle and safe end is followed by similar metal weld between safe end and pipe. And thus residual stress in dissimilar metal weld can be affected by similar metal weld. Similar metal weld impose bending stress on dissimilar metal weld, which is according to the length of safe end. In this study, simple nozzle model which covers various radius to thickness ratios was proposed to quantify residual stress in dissimilar metal weld based on finite element analyses. As a result, short length of safe end was proved to be more effective to mitigate residual stress in dissimilar metal weld and critical effective length of safe end is provided according to the radius to thickness ratio.


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