Importance of repairing structures in nuclear power plants as ountermeasures for Stress Corrosion Cracking is increasing be use many plants are aging. We have developed the underwater laser beam welding (ULBW) for the repair technique. In order to achieve faster and widespread repairing, we focused on a top-ht type laser beam and hot-wire system. The top-hat type laser eam has oblong energy distribution and contributes to expand heating area. The hot-wire system heats the welding wire befor e insertion and...
英字タイトル:
A High Efficiency Method of Repairing Metal Structure using Local Laser Heating

Toshiba has developed temper bead welding by under water laser welding as SCC counter measure for aged components in PWR and BWR nuclear power plants. Temper bead welding by under water laser welding technique recovers toughness of low alloy steel reactor vessel by employing proper the number of cladding layers and their welding conditions. In th is report, some evaluation results of material characteristics of temper bead welded low alloy steel are presented....
英字タイトル:
Development of temper bead welding by under water laser welding

Toshiba has developed various laser-based maintenance and repair technologies and already applied to nuclear power plants. Laser beam welding technology has been developed as an SCC cou ntermeasure for aged components in PWRs and BWRs. This technology can also be used underwater by blowing shielding gas for creating a local dry area. This welding equipment has damage d etecting function of optical elements such as windows and optical fiber cables, and the laser beam spot position and diameter can be adjust...
英字タイトル:
Development of Underwater Laser Beam Welding Equipment