Journal of the Korean Society for Nondestructive Testing (비파괴검사학회지)

The Korean Society for Nondestructive Testing (한국비파괴검사학회)
권호 표지
DOI QR코드

DOI QR Code

A Study on the Chemical Cleaning Process and Its Qualification Test by Eddy Current Testing

  • Received : 2013.10.14
  • Accepted : 2013.12.14
  • Published : 2013.12.30
Download PDF
⟨ Previous Next ⟩

Abstract

Steam Generator (SG) tube, as a barrier isolating the primary coolant system from the secondary side of nuclear power plants (NPP), must maintain the structural integrity for the public safety and their efficient power generation. So, SG tubes are subject to the periodic examination and the repairs if needed so that any defective tubes are not in service. Recently, corrosion related degradations were detected in the tubes of the domestic OPR-1000 NPP, as a form of axially oriented outer diameter stress corrosion cracking (ODSCC). According to the studies on the factors causing the heat fouling as well as developing corrosion cracking, densely scaled deposits on the secondary side of the SG tubes are mainly known to be problematic causing the adverse impacts against the soundness of the SG tubes [1]. Therefore, the processes of various cleaning methods efficiently to dissolve and remove the deposits have been applied as well as it is imperative to maintain the structural integrity of the tubes after exposing to the cleaning agent. So qualification test (QT) should be carried out to assess the perfection of the chemical cleaning and QT is to apply the processes and to do ECT. In this paper, the chemical cleaning processes to dissolve and remove the scaled deposits are introduced and results of ECT on the artificial crack specimens to determine the effectiveness of those processes are represented.

Keywords

References

  1. Atomic Energy Society of Japan, "Handbook of Water Chemistry of Nuclear Reactor System," Corona Publishing Co. Tokyo, p. 170 (2000)
  2. S. Odar and K. Kuhnke, "The KWU chemical cleaning process as a remedial measure to improve steam generator performance," Proc. Int. Conf. Water Chemistry of Nuclear Systems, Water Chemistry 6, British Nuclear Energy Society, p. 113 (1992)
  3. H. Forch, T. Oliver and W. Hertle, "Chemical cleaning of PWR steam generators with a low temperature process," Nucl. Eng. Des., p. 147, p. 115 (1993)
  4. G. Jacobi, B. Markgraf, H. R. Sauer, K. Seidelmann and S. Odar, "KWU's hightemperature chemical cleaning process application in German PWRs to improve steam generator performance," Proc. Int. Conf. Water Chemistry of Nuclear Systems, Water Chemistry 8, British Nuclear Energy Society, pp. 207-212 (2000)
  5. B. Dow and R. Thomas, "Chemical cleaning review," Nucl. Eng. Int., p. 40, p. 38 (1995)
  6. S. Odar, "KWU high temperature chemical cleaning process control," Proc. Int. Conf. Water Chemistry of Nuclear Systems, Water Chemistry 7, British Nuclear Energy Society, pp. 335-340 (1996)
  7. H. Kawamura, K. Fujiwara, H. Kanbe, H. Hirano, H. Takiguchi, K. Yoshino, S. Yamamoto, T. Shibata and K. Ishigure, "Applicability of chemical cleaning process to steam generator side(III)," Journal of Nuclear Science and Technology, Vol. 43, No. 6, pp. 655-668 (2006) https://doi.org/10.1080/18811248.2006.9711145
  8. K. Fujiwara, "Applicability of chemical cleaning process to steam generator side(I)," Journal of Nuclear Science and Technology, Vol. 41, No. 1 pp. 44-54 (2004) https://doi.org/10.1080/18811248.2004.9715456
  9. J. M. Jevec and W. S. Leedy, "Chemical Cleaning Solvent and Process Testing," EPRI NP-2976, (1983)
  10. D. P. Rochester, D. Ltate and R. P. Dow, "Optimization of the EPRI/SGOG steam generator chemical cleaning copper solvent," Proc. Int. Conf. on Water Chemistry in Nuclear Power Plants, Water Chemistry '91, Japan Atomic Industrial Forum, Fukui, Japan, 229 (1991)
  11. Central Research Institute of KHNP, "Chemical cleaning assessment for defect tube, Rev. 0," pp 1-6 (2012)