Degradation of Steam Generator Tubing and Components by Operation of Pressurized-Water Reactors

摘要

Experience in operating pressurized water reactors (PWR) has shown a number of materials degradation processes to have occurred in their steam generators. These include stress corrosion cracking (SCC), intergranular attack, generalized dissolution, and pitting attack on steam generator tubes; mechanical damage to steam generator tubes; extensive corrosion of tubing support plates (denting); and cracking of feedwater lines and steam generator vessels. The current status of the understanding of the causes of each of these phenomena is reviewed with emphasis on their possible significance to reactor safety and directions the nuclear industry and the NRC should be taking to reduce the rate of degradation of steam generator components. (ERA citation 08:009787)