JRR-3冷中性子源装置の減速材容器ユニットの更新

Replacement of the moderator cell unit of JRR-3's cold neutron source facility

羽沢 知也; 永堀 和久; 楠 剛 

Hazawa, Tomoya; Nagahori, Kazuhisa; Kusunoki, Tsuyoshi

減速材容器は液体水素を貯留するためのステンレス鋼製の容器で、中性子照射脆化により、その寿命が約7年と定めている。研究炉利用課では国内での製作も視野に入れながら調査を開始、国内で減速材容器を製作し、2006年2月に交換作業を終了した。交換作業終了後、中性子特性測定を行い、従前のフランス製の減速材容器と同等な性能を有していることを確認し、減速材容器の国産化に成功した。

The moderator cell containing liquid hydrogen is made of stainless steel. The material irradiation lifetime is limited to 7 years due to irradiation brittleness. The survey and design for a renewal moderator cell were conducted with a view to domestic production by the JAEA. It was fabricated and replaced by a domestic company, and the replacement work was completed in February, 2006. Characteristic was measured after exchange, and it had the same performance as the moderator cell made in France, and succeeded in making to domestic production.