T. Kishi, National Institute for Materials Science, Japan; N. Uesugi, JAPEIC, Japan
ABSTRACT
Safety assurance of nuclear power plants is highly depended on a thorough going preventive maintenance. Since there are many nuclear power plants with longer operating intervals in Japan, the long-term maintenance plan in consideration of the operation age is introducing to attain their safety assurance. In recent years, cracks by high cycle thermal fatigue were found at the outlet pipes of a heat exchanger, and also the cracks of SCC type were detected at the welded joints of nickel based alloy of core internal. To avoid similar events, NDE inspections are being carried out to ensure the structural integrity of the plants, together with the investigation of the preventive measures. In view of the diversification of the aging degradation phenomena in nuclear power plants and a complete preventive maintenance, it is necessary to develop the NDT techniques applicable for automatic inspection for a large area and the techniques for improving the delectability of dissimilar metal welds. Moreover, it is important to promote the continuous research activities, which produce potential scientific knowledge and technology for regulation activities.
Publication Source: 3nd International Conference on NDE in Relation to Structural Integrity for Nuclear and Pressurized Components, November 14-16, 2001, Seville Spain. Publisher: Tecnatom s.a. - [Homepage]
