Preventive and corrective actions for tube degradation and new steam generator design concepts

In order to maintain the tube integrity of operating steam generators, it is important to implement the preventive and corrective actions against the recurrence of tube degradation as well as the determent of propagation of that. Whenever any tube degradation is first detected, all the operating units will be reviewed and inspected, and the preventive and corrective actions will, if necessary, be implemented. On the other hand, many improvements have been made in steam generator design since the first nuclear power plant has constructed. Based upon the various domestic and foreign operating experiences, new steam generators are designed with emphasis on tube material, tube support plate, materials and structures, secondary flow patterns, moisture separator performance, etc.. (author)