Development of inspection repair technology for tube inner wall of aging nuclear power plants

Ito, Fuyumi; Nishimura, Akihiko  ; Yonemoto, Yukihiro*; Terada, Takaya; Shimada, Yukihiro

Development of inspection repair technology for tube inner wall of aging nuclear power plants was described. Three functions of the pulse laser, observation by the composite-type optical fiber scope, and laser-induced breakdown spectroscopy (LIBS) are built into a coupling device. In addition, to facilitate the observation of the cracks, we adopted the magnetic particle testing (MT). And to remove the dispersed magnetic particle liquid from cracks after MT, we manufactured a microcapsule containing the magnetic particle liquid. Furthermore, pulse laser ablation with LIBS can clean up the oxide layer of the inner wall of heat exchanger tubes. Applying LIBS on tube inner wall before MT can give us the information about cracks and defects.