Due to the core shroud cracks reported from numerous BWRs including the German KWU type BWR Wuergassen, a RPV internals management program for the Gundremmingen NPP (KRB-II) has been initiated in 1994. Major steps and the main results of this program are presented. As an interim result, surface condition of the weld regions and controlled post weld heat treatment (PWHT) in order to reduce the residual stresses seem to play an important role for resistance to crack initiation and growth. To support these assumptions, results of related R&D projects of the German utilities (VGB) are presented.

This content is only available via PDF.
You do not currently have access to this content.