燃料照射試験用再計装機器のメカニカルシール機構の開発

Development of mechanical seal structure for reuse of re-instrumentation device used in fuel irradiation test

井上 修一 ; 山浦 高幸 ; 斎藤 隆; 石川 和義; 菊地 泰二; 相沢 静男; 土谷 邦彦 

Inoue, Shuichi; Yamaura, Takayuki; Saito, Takashi; Ishikawa, Kazuyoshi; Kikuchi, Taiji; Sozawa, Shizuo; Tsuchiya, Kunihiko

材料試験炉(JMTR)では、シュラウド照射装置「OSF-1」や沸騰水キャプセルを用い、発電炉で使用された燃料試料の出力急昇を伴う照射試験を数多く行った。同燃料照射に用いる燃料試料には、遠隔で行う溶接により、熱電対やFPガス圧計のような再計装機器を直接取付けられていた。本開発では、再計装機器の利用効率の向上を図ることを目的に、従来の溶接の代わりに当該機器の再使用を可能にする機械的な接続方法、すなわち「メカニカルシール機構」を考案し、その構造の設計,試作及び確証試験を行った。試作したメカニカルシール機構の試験体は、各種確証試験において良好な結果を示し、再計装機器の再利用が可能となる見通しを得た。

In Japan Material Testing Reactor (JMTR), a lot of experiments of fuel irradiation with the power ramping tests have been performed by using the shroud irradiation facility and the Boiling Water Capsule (BOCA). The fuel samples used in these tests were welded to re-instrumentation devices such as thermocouples and FP gas pressures. In this development, the mechanical connection method as "mechanical seal structure", that enables the re-use of re-instrumentation devices, was adopted in order to improve the utilization efficiency of the device. The test samples with mechanical seal structure were fabricated and the confirmatory tests such as He leakage test, thermal cycle test, autoclave test, etc. were carried out. The test samples with the mechanical seal structure showed an excellent result in various confirmatory tests, and the prospect are bright for the re-use of re-instrumentation devices with the mechanical seal structure.