Structural materials and code development for Japanese sodium-cooled fast reactors

日本におけるナトリウム冷却高速炉用構造材料および構造規格体系の開発

浅山 泰 ; 永江 勇二 ; 若井 隆純 ; 月森 和之; 森下 正樹 

Asayama, Tai; Nagae, Yuji; Wakai, Takashi; Tsukimori, Kazuyuki; Morishita, Masaki

本報ではJSFR(Japan Sodium-cooled Fast Reactor)に適用する高温構造設計規格体系の開発の現状について紹介する。これまでの研究開発成果に基づき、JSFR用候補材料である316FR鋼および改良9Cr-1Mo鋼が新たに日本機械学会発電用原子力設備規格設計・建設規格第II編高速炉規格に登録された。今後、2016年の次期主要改訂に向けて、時間依存型許容値の500,000時間までの拡張および対応する設計評価法の高度化を行うことに加え、設計・建設規格以外に必要な規格等、すなわち、溶接規格、維持規格、破断前漏えい評価規格、機器構造信頼性評価ガイドラインを策定し高速炉用規格体系を整備すべく、研究開発および規格化活動を進めてゆく。

This paper describes the latest status on the development of elevated temperature materials and structural codes for Japanese sodium-cooled fast reactors (SFRs). Based on the extensive research and development activities in the last decades in Japan, two materials, 316FR and Modified 9Cr-1Mo steels were newly incorporated into the 2012 Edition of Fast Reactor Design and Construction Code of the Japan Society of Mechanical Engineers (JSME). Structural design methodologies are continuously being improved towards the next major revision planed in 2016 Edition where methodologies for a 60-year design of Japanese demonstration fast reactor will be provided. Codes and guidelines for fitness-for-service, leak-before-break evaluation and reliability assessment are concurrently being developed utilizing the System Based Code concept aiming at establishing an integrated code system that encompasses a life cycle of SFRs.