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Stress Distributions at the Dissimilar Metal Weld of Safety Injection Nozzles According to Safe-end Length and SMW Thickness

안전단 길이 및 동종금속용접부 두께 변화에 따른 안전주입노즐 이종금속용접부의 응력분포

  • Kim, Tae-Jin (Dept. of Mechanical System Design Engineering, Seoul Nat'l Univ. of Science and Technology) ;
  • Jeong, Woo-Chul (Dept. of Mechanical System Design Engineering, Seoul Nat'l Univ. of Science and Technology) ;
  • Huh, Nam-Su (Dept. of Mechanical System Design Engineering, Seoul Nat'l Univ. of Science and Technology)
  • 김태진 (서울과학기술대학교 기계시스템디자인공학과) ;
  • 정우철 (서울과학기술대학교 기계시스템디자인공학과) ;
  • 허남수 (서울과학기술대학교 기계시스템디자인공학과)
  • Received : 2015.04.08
  • Accepted : 2015.04.28
  • Published : 2015.10.01

Abstract

In the present paper, we evaluate the effects of the safe-end length and thickness of the similar metal weld (SMW) of safety injection nozzles on stress distributions at the dissimilar metal weld (DMW). For this evaluation, we carry out detailed 2-D axisymmetric finite element analyses by considering four different values of the safe-end length and four different values of the thickness of SMW. Based on the results obtained, we found that the SMW thickness affects the axial stresses at the center of the DMW for the shorter safe-end length; on the other hand, it does not affect the hoop stresses. In terms of the safe-end length, the values of the axial and hoop stresses at the inner surface of the DMW center increase as the safe-end length increases. In particular, for the cases considered in the present study, the stress distributions at the DMW center can be categorized according to certain values of safe-end length.

Keywords

Welding Residual Stress;Dissimilar Metal Weld;Similar Metal Weld;Primary Water Stress Corrosion Cracking;Nozzle;Finite Element Analysis

Acknowledgement

Supported by : 한국에너지기술평가원(KETEP)

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