Development of welding techniques for assembling of IASCC Test Capsule

Shibata, Akira ; Kawamata, Kazuo; Taguchi, Taketoshi ; Kaji, Yoshiyuki  ; Shimizu, Michio*; Kanazawa, Yoshiharu; Matsui, Yoshinori ; Iwamatsu, Shigemi; Sozawa, Shizuo; Tayama, Yoshinobu; Nakagawa, Tetsuya; Omi, Masao

Irradiation assisted stress corrosion cracking (IASCC) is considered to be one of the key issues from a viewpoint of the life management of core components in the aged Light Water Reactors. The in-situ crack extension examination and the in-situ constant load tensile test in the reactor are required for the study of IASCC. There are, however, some technical hurdles to be overcome for the experiments. For this in-situ IASCC test, techniques for assembling pre-irradiated specimens into an capsule in a hot cell by remote handling are necessary. In this report, I describe the establishment of those remote assembling techniques and development of new welding apparatus and the TIG upset welding for stainless tube of 3 mm in thickness. Already IASCC capsules having pre-irradiated CT specimens were remotely assembled using these techniques in the hot cell for performing crack growth tests under irradiation in JMTR. And eight in-situ IASCC capsules have been finished successfully in JMTR.