| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To suppress stress corrosion damage to structural material to increase a service life of equipment by improving a stress state of the surface of a structure inside reactor water inside a nuclear reactor pressure vessel. <P>SOLUTION: A vertically movable and rotatable folding arm 13 is suspended from an upper part of the nuclear reactor pressure vessel 7 by wires 8, is passed through an upper lattice plate opening part 11, and is installed in an upper lattice plate lower chamber 28. An installation base 20 of the arm 13 is installed with a laser irradiation device. The installation base 20 is provided with a repair work device 14 for delivery, and pulse laser light of visible light is irradiated by the laser irradiation device while scanning a prescribed range by a prescribed range, so as to apply laser machining to the inner face of a shroud 15. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
