ASN authorises use of the Flamanville EPR reactor vessel closure head until the first refuelling outage of the reactor

Published on 31/05/2023 at 14:44

Information notice

The commissioning and operation of the Flamanville EPR reactor pressure vessel were authorised by an ASN resolution in 2018. This resolution took into account a manufacturing anomaly in the lower dome and the vessel closure head and limited the use of the vessel closure head to 31 December 2024.

On the date of issue of the resolution, reactor start-up was planned for autumn 2019. Due to the delays in reactor construction, EDF now plans commissioning the reactor in the first quarter of 2024.

The replacement closure head is currently being manufactured at Framatome. The manufacturing operations are being monitored by ASN. Delivery of the replacement closure head is planned for the end of summer 2024.

Framatome sent ASN a request to push back the date limit for use of the closure head currently in place to allow its replacement during the first refuelling outage of the reactor, scheduled between 15 and 18 months after commissioning. The closure head utilisation time would be less than that envisaged in 2018 when ASN authorised reactor vessel commissioning, and pushing back the date limit as requested would avoid having a specific reactor outage between the start and end of 2024 to replace the closure head.

ASN deemed Framatome's request acceptable and has authorised use of the closure head until the reactor's first refuelling outage. ASN nevertheless considers that, should the project suffer another significant delay, the licensee (EDF) will have to reconsider the possibility of replacing the closure head before commissioning the reactor.


Date of last update : 31/05/2023