Structural integrity assessment of pressure tubes for Wolsong Unit 1 based on operational experiences

摘要

Pressure tube integrity has been considered as a key issue since the first operation of the CANDU reactor. Wolsong Unit 1 has been in service since 1983 and subjected to inspections three times covering 44 tubes. The in-service Inspections revealed that a major portion of inspected tubes was in contact with calandria tubes. This is likely to Increase the probability of blister formation which is a potential threat to pressure tube integrity. Fortunately, the Inspection results indicated that no tube has been affected by blister formation so far.