Flamanville 3: complementary justifications on three nozzles of the primary circuit

A significant safety event was declared by EDF to the French safety authority on March 3. This event is related to an incomplete consideration of the study referential requirements for the implantation of three nozzles on the main primary circuit at Flamanville 3 EPR reactor.

Framatome Engineering teams, as a support of EDF teams, have launched an instruction aiming at precisely determining the causes of the event. In order to propose an adequate treatment plan, they also initiated the reassessment of the nozzles characteristics in regards to the study referential.

These nozzles allow to connect auxiliary circuits to the components of the primary circuit. They can be integrated to the piping during the manufacturing operations by machining the mass or can be connected by welding.

The concerned nozzles were done in 2011 based on a 2006 design file.

Find out more:
> ASN information notice published on March 16, 2021 (French version only)
> EDF information notice published on March 4, 2021 (French version only)