During the operation of nuclear power plant, the stress corrosion cracking in the tube wall of nuclear steam generators can be observed. Once the degradation is recognized, the tube must be repaired using the method of plugging or sleeving. Nd:YAG laser welded sleeving is one of the most promising technologies for sleeving repair when considering the radioactive working conditions in a nuclear power plant. In this paper, the characteristics of laser welding for repairing a steam generator tube were investigated. The effects of average laser power, laser energy intensity, welding speed, pulse duration and frequency are evaluated experimentally. Based on these results, Nd:YAG laser welded sleeving is applied to repair the degraded steam generator tubes in real system. (C) 2001 Published by Elsevier Science B.V.
