DOI QR코드

DOI QR Code

개선된 SA508-Gr.1a 배관재의 파단전누설평가 여유도 분석

Leak-Before-Break Assessment Margin Analysis of Improved SA508-Gr.1a Pipe Material

  • 김만원 (한국수력원자력(주) 중앙연구원) ;
  • 이요섭 (한국수력원자력(주) 중앙연구원) ;
  • 신인환 (한국수력원자력(주) 중앙연구원) ;
  • 양준석 (한국수력원자력(주) 중앙연구원) ;
  • 김홍덕 (한국수력원자력(주) 중앙연구원)
  • 투고 : 2020.04.29
  • 심사 : 2020.05.26
  • 발행 : 2020.06.30

초록

The effect of improving the tensile and J-R fracture toughness properties of SA508 Gr.1a on the LBB margin for the main steam pipe is investigated. The material properties and microstructure images of the existing main steam piping material SA106 Gr.C used in domestic nuclear power plants and the newly selected material SA508 Gr.1a were compared. For each material, LBB margins were calculated and compared through finite element analysis and crack instability evaluation. The LBB margin of the improved SA508 Gr.1a is found to be greatly improved compared to that of the existing SA106 Gr.C and SA508 Gr.1a. This is because of the increased material's strength and J-R fracture toughness compared to the previous materials. In order to analyze the effect of physical property change on the LBB margin, the sensitivity of each LBB margin according to the variation of tensile strength and J-R fracture toughness was analyzed. The effect of the change in tensile strength was found to be greater than that of the change in fracture toughness. Therefore, an increase in strength significantly influenced the improvement of the LBB margin of the improved SA508 Gr.1a.

키워드

참고문헌

  1. Song, M. S., 2006, "The Effect of Weld Residual Stress on Crack Opening Displacement and LBB Evaluation for OPR1000 Surge Line," Trans. of the KPVP, Vol. 2, No. 1, pp. 66-74.
  2. Lee, S. Y., Kim, N. H., Koo, G. H., Kim. S. K. and Kim, Y. J., 2016, "Preliminary Leak-before Break Assessment of Intermediate Heat Transport System Hot-Leg of a Prototype Generation IV Sodium-cooled Fast Reactor," Trans. of the KPVP, Vol. 12, No. 1, pp. 126-133. doi: http://dx.doi.org/10.20466/KPVP.2016.12.1.126
  3. Kim, M. W. and Park, Y. S, 2013, "A Simple Finite Element Modeling Method for Leak-Before-Break Crack Analysis of Pipe with Overlay Dissimilar Metal Weldments," Trans. of the KPVP, Vol. 9, No. 1, pp. 70-76.
  4. KEPCO-E&C, 2012, "Technical Report : Leak- Before-Break for Main Steam Line," KEPCO Engineering & Construction Company. INC, Kimcheon-si, 9-037-N460 -001 Rev.0.
  5. KHNP, 2019, "Development of Technologies for Improving Mechanical Properties of Main Steam Piping: Final Report," Korea Hydro & Nuclear Power Co. Ltd., Daejeon, 2019-50003339-전-0917FR.
  6. Kim, J. W., Cho, H. G., Kim, M. W. and Kim, H. D., 2017, "Analysis of Tensile and J-R Fracture Toughness Data for LBB Evaluation of Low-alloy Steel Pipes," Proc. of 2017 KPVP Conference, Changwon, Nov. 23- 24, pp. 227-228.
  7. KEPRI, 2011, "Material Property Test for Main Steam Pipe of APR-1000 (Final Report)," Korea Electric Power Research Institute, Daejeon.
  8. ABAQUS/CAE Ver.6.10-3, 2010, (C) Dassault Systemes Simulia Corp., USA.
  9. USNRC, 2008, "Guidance on Monitoring and Responding to Reactor Coolant System Leakage," Regulatory Guide 1.45 Revision 1, U.S. Nuclear Regulatory Commission, Washington, DC.
  10. EPRI, 1987, "PICEP: Pipe Crack Evaluation Program (Revision 1) Special Report," Electric Power Research Institute, Palo Alto, California, NP-3596-SR Rev.1.