Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Investigation of the Performance Based Structural Safety Factor of Elbows in Nuclear Power Plants

원전 엘보우의 성능기반 안전여유도 분석

  • 이성호 (한전전력연구원 원자력발전연구소) ;
  • 박치용 (한전전력연구원 원자력발전연구소) ;
  • 박재학 (충북대학교 안전공학과)
  • Published : 2009.08.01
Download PDF
⟨ Previous Next ⟩

Abstract

The piping systems in nuclear power plant are composed of various typed pipes such as straight, elbow pipe, branch and reducer etc. The elbow is connected from straight pipe to another pipes in order to establish the complicated piping system. Elbow is one of very important components considering management of wall thinning degradation. It is however applied by various loads such as system pressure, earthquake, postulated break loading and many transient loads, which provoke simply the internal pressure, bending and torsional stress. In this study, firstly pipes in the secondary system of the nuclear power plant are classified as pipe size and type for selecting the investigating range. Next, a large number of finite element analysis considering the all typed dimensions of commercial pipe has been performed to find out the behavior of TES(twice elastic slop) plastic load of elbows, which is based on evaluation of the structural safety factor. Finally performance based structural safety factor was investigated comparing with maximum allowable load by construction code.

Keywords

References

  1. Frank, M., Hans, R., and Helmut, S., 2001, 'Experience with Piping in German NPPs with Respect to Ageing-Related Aspect,' Nuclear Engineering and Design, Vol. 207, pp. 307~316 https://doi.org/10.1016/S0029-5493(01)00339-9
  2. INPO, 2006, 'Flow-Accelerated Corrosion, 'Engineering Program Guideline
  3. Zhang, L., Wang, Y., Chen, J. and Liu, C., 2001, 'Evaluation of Local Thinned Pressurized Elbows,' Int. J. of Pressure Vessels and Piping, Vol.78, pp. 697~703 https://doi.org/10.1016/S0308-0161(01)00125-9
  4. Kim, J.W., Park, C.Y. and Kim, B.N., 2001, 'Evaluation of Local Wall Thickness of Thinned Pipe Subjected to Internal Pressure and Bending Moment,' Trans. of KSME (A), Vol. 25, No. 1, pp. 81~88
  5. Kim, J.W., Kim, T.S. and Park, C.Y., 2004, 'Effect of Local Wall Thinning Defect on the Collapse Moment of Elbow,' Trans. of KSME (A), Vol. 27, No. 4, pp. 402~409 https://doi.org/10.3795/KSME-A.2004.28.4.402
  6. Lee, S.H., et. al., 2008, Optimization of Thinned Pipe Management Program and Application, Korea Hydro & Nuclear Power Co.
  7. Chattopadhyay, J., Kushwaha, H.H. and Roos, E., 2009, 'Improved Integrity Assessment Equations of Pipe Bends,' Int. J. of Pressure Vessel and Piping, Vol. 86, No. & pp. in Press https://doi.org/10.1016/j.ijpvp.2008.12.005
  8. Oh, C.S., Kim, Y.J. and Park, C.Y., 2008, 'Shakedown Limit Loads for elbows under Internal Pressure and Cyclic in-Plane Bending,' Int. J. of Pressure Vessel and Piping, Vol. 85, No. 6, pp.394~405 https://doi.org/10.1016/j.ijpvp.2007.11.009
  9. ASME, 1998 ed., ASME Boiler and Pressure Vessel Code, Sec. III, Div. 1, Subsection NC/ND and B31.1