Effect of sea water intrusion from main condenser, damaged by break on reactor core internals, Hamaoka Unit 5 (No.3)
綿貫 理研 Yoshiaki WATANUKI 今井 富康 Tomiyasu IMAI 塚田 匡 Tadashi TSUKADA 黒野 晃平 Kouhei KURONO 丹羽 勇太 Yuuta NIWA
condenser pipe breakcorrosionfield experienceplant surveysea water intrusion
In the process of achieving cold shutdown following the shutdown of Hamaoka Nuclear Power Station Unit 5 on May 14, 2011, large quantities of seawater flowed into the reactor and other facilities due to main condenser tubes which had broken. The investigations focusing on corrosion of materials had been conducted through various methods, observation of equipments, material tests, cleaning tests, and inspection of RPV and its components. Based on these investigations, we had evaluated the impact on the reactor facilities due to the inflow of seawater. On Dec 15, 2015, we had summarized health assessment which had been reviewed by academic experts.