Presentation Information
[1D12]Internal Inspection of the Reactor Pressure Vessel at Unit 2, Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company (TEPCO)(2) Investigation Implementation
*Go Ono1, Tatsunori Watanuki1, Noritaka Moriwaki1, Yusuke Aoki1, Kenichi Magariyama2, Takuto Hanafusa2, Yoichi Sakuragi2, Masashi Yamada3, Shunsuke Kurosawa4, Masanori Hatori5 (1. TOSHIBA, 2. TEPCO HD, 3. Olympus, 4. Nagoya Univ., 5. Decom.Tech)
Keywords:
Fukushima Daiichi NPS,Reactor Pressure Vessel,Radiation-Resistant fiberscope
Following the previous presentation, this paper reports on the route construction and implementation of the internal investigation of the Reactor Pressure Vessel (RPV) at Unit 2 of Tokyo Electric Power Company Holdings’ Fukushima Daiichi Nuclear Power Station.
The investigation was based on a policy of utilizing existing reactor water level instrumentation piping, and the piping connected to the N16A nozzle was selected based on mock-up test results and site conditions. To secure access while maintaining the existing confinement boundary, a configuration combining a pipe-freezing method with a water-sealed boundary was adopted. Candidate endoscope specifications were comparatively evaluated, and the optimal model was selected from the perspective of insertability. In addition, to ensure reliable operation under high-radiation conditions, prior training was conducted using a full-scale mock-up facility, through which operational procedures and role assignments were optimized. As a result, safe and reliable access to the RPV interior and successful completion of the investigation were achieved. This report presents the details of these efforts.
The investigation was based on a policy of utilizing existing reactor water level instrumentation piping, and the piping connected to the N16A nozzle was selected based on mock-up test results and site conditions. To secure access while maintaining the existing confinement boundary, a configuration combining a pipe-freezing method with a water-sealed boundary was adopted. Candidate endoscope specifications were comparatively evaluated, and the optimal model was selected from the perspective of insertability. In addition, to ensure reliable operation under high-radiation conditions, prior training was conducted using a full-scale mock-up facility, through which operational procedures and role assignments were optimized. As a result, safe and reliable access to the RPV interior and successful completion of the investigation were achieved. This report presents the details of these efforts.
Comment
To browse or post comments, you must log in.Log in