浜岡原子力発電所5号機における制御棒駆動水系配管溶接継手の漏えい事象に関する原因調査について

英字タイトル:
Investigation on leakage point of welding part of control rod drive system piping of Hamaoka NPS unit5.
著者:
服部宗仁今井富康黒野晃平江上次孝丹羽勇太（中部電力）
発刊日: 2018年7月10日
公開日: 2021年9月30日

カテゴリ: 第15回

キーワードタグ:
condenser pipe breakcorrosionsea water intrusionSUS weld metal cladding

概要

In this research, research into the causes of the event of piping micro leakage of Hamaoka Nuclear power plant Unit 5 was carried out .Due to main condenser tube damage in May, 2011, seawater flowed into the reactor and other facilities of Unit 5. After that, piping purification was carried out and kept filled with water. Crevice corro- sion was confirmed at the leakage piping and it was estimated to happen at purification process. The leakage piping would not be cleaned sufficiently in the purification process. Three factors were found to be related to corrosion of stainless steel. Chloride ion by seawater, piping weld and influence of internal deposits. Lateral spread inspection is also carried out for places having similar conditions.