| 摘要 |
PURPOSE:To prevent cracking in a structure of a plant by forming a stop hole by irradiating the tip part of a notch in the structure with a laser beam. CONSTITUTION:The laser beam 2 is radiated to the tip part of the notch 6 in the structure 5 with a notch 6 shape or the tip part of cracking in the structure in which crack is generated. The stop hole 7 is formed by this irradiation. By radiating the laser beam to the tip part of notch or cracking, that part is smelted and worked into round shaped solidified structure contg. ferrite. By radiating the laser beam to the inside surface and the vicinity of the stop hole, that part is subjected to solution treatment. By radiating the laser beam to both sides of notched part or cracking, those parts are heated and cooled. In this way, the life of the plant of a light-water reactor or the like can be prolonged. |
