Journal of the Computational Structural Engineering Institute of Korea (한국전산구조공학회논문집)

Computational Structural Engineering Institute of Korea (한국전산구조공학회)
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Effect of Similar Metal Weld & Preemptive Weld Overlay On Residual Stress of Repair Weldment In Surge Nozzle

고리 원전 밀림관 노즐의 동종용접과 예방용접 Overlay가 보수용접 잔류응력에 미치는 영향

  • Received : 2009.09.28
  • Accepted : 2009.11.11
  • Published : 2009.12.30
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Abstract

Welding residual stress is occurred after welding process. Tensile residual stress is one factor of PWSCC. Repair welding usually happened during the manufacturing welding process. Repair welds cause strong tensile residual stress. In PWR, Repair weldments made by Alloy 82/182 is susceptible to PWSCC caused by tensile stress, material and environment. Therefore, mitigation of welding residual stress in weldments is important for reliable operating. PWOL is one of the methods for mitigation and verified for over twenty years. In this paper, residual stress distribution of repaired weldments and the effect of PWOL on mitigation is examined for surge nozzle.

용접과정 중 발생되는 인장잔류응력은 원전 배관 이종용접부의 PWSCC가 발생되는 원인 중 하나라고 알려져 있다. 일반적으로 보수용접은 용접과정 중 흔히 일어나는 현상이다. 보수용접은 강한 인장잔류응력을 유도하기 때문에 이종용접부의 PWSCC를 유도하기 쉽다. 본 논문에서는 강한 인장잔류응력이 발생되는 보수용접부에 대해 보수용접 깊이에 따라 동종용접과 예방용접 overlay로 인하여 인장잔류응력의 크기가 변화하는 것을 정량적으로 확인하였다.

Keywords

References

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