Qualification of remedial methods to prevent primary-side stress corrosion cracking of steam generator tubing: Volume 1, Shot peening: Final report

Primary side cracking has been observed within the mechanically expanded area in a significant number of tubes of PWR steam generators in Europe, in Japan and to a lesser extent in the USA. A program was launched by the Belgian utilities and was further cosponsored by the Steam Generator Owners Group (SGOG)/Electric Power Research Institute (EPRI) to develop preventive actions applicable to steam generators under radioactive and/or non-radioactive conditions. These preventive measures included: introduction of residual compressive stresses on ID by shot- or roto-peening without inducing unacceptable tensile stresses on OD; and stress relaxation and metallurgical improvement of the material by an in situ heat treatment of the whole tubesheet. The qualification and first site application of shot-peening are presented in this volume of the report. Roto-peening and global heat treatment are presented respectively in Volumes 2 and 3