ICONE19-43221 Planning of Environmental Mitigation for Stress Corrosion Cracking of BWR Core Internals by Means of Noble Metal Chemical Addition and of Electrochemical Corrosion Potential Measurement

Abstract

Noble Metal Chemical Addition (NMCA) [1-2] is planned to be applied in Tokai Daini Power Station (Tokai-2, BWR, 1,100MWe, commenced commercial operation on November in 1973) after the 25th outage for environmental mitigation for Stress Corrosion Cracking (SCC) of BWR core internals, PLR pipes and so on. In addition, it is also planned to measure Electrochemical Corrosion Potential (ECP) at some locations such as core internals in order to check the mitigation effect of NMCA. This paper describes the outline of this proactive project, as well as explaining challenges of Japanese Code on Fitnessfor- Service (FFS Code) [3] to reflect ECP evaluation results on SCC assessment. Orientation for solutions of these challenges of FFS Code is also discussed.