炉内検査装置用超音波センサの「常陽」への適用性検討

Investigation of application of acoustic sensor for the equipment of in-vessel structure's inspection to "JOYO"

唐沢 博一*; 小川 不二雄*; 佐藤 孝男*; 泉 守*; 小舞 正文*

not registered; not registered; not registered; not registered; not registered

高速炉の供用期間中検査に関する技術開発の一環として,原子炉運転中の炉心の挙動を超音波技術によって観測する炉内検査装置について,以下の検討を行った。・照射試験用の超音波センサを試作するとともに,その性能試験を行い,500までの耐熱性を確認した。・炉内検査装置の駆動部,ケーブル,コネクタ等の仕様を検討し,「常陽」の実機条件を考慮して取扱可能な装置の構造概念を明らかにした。・照射試験を行う場合の照射条件を検討し,必要な照射量や照射位置を明らかにするとともに,燃料ラック内のサーベイランスリグで照射試験が可能であることを確認した。

As a part of the development of ISI (In-Service Inspection), the investigations regarding the inspection equipment which can observe the distortion of core assemblies under operating condition with ultrasonic measuring technique were performed as follows. (1)The test elements of high temperature ultrasonic sensor for the irradiation test in operating condition were manufactured. And it was confirmed that the elements had good performance under 500 C air condition. (2)The specifications of drive mechanism, cable and connector were clarified. And structure of the inspection equipment was investigated in consideration to conditions of actual plant in JOYO. (3)As the condition of irradiation test, the neutron flux which should be irradiated and the arrangement of the test elements in a test rig were estimated. It was confirmed that the irradiation test condition can be realized in the severance-rig within a fuel lack.