All socket welds on auxiliary piping at French nuclear plants are to be replaced, following a ruling by the country's nuclear safety authority, the ASN.
The ASN said that socket welded pipes must be replaced with butt joints if they do not meet the existing French standard. The ruling will affect all 34 of the 900MWe PWRs operated by Electricité de France (EdF).
Socket welds had been allowed when the 900MWe PWRs were built. However, the ASN said they are now prohibited under revised technical specifications. Furthermore, they also pose difficulties for in-service inspections.