ASN gives go-ahead for Flamanville RPV

12 October 2018

France's nuclear safety regulator, the Autorité de Sûreté Nucléaire (ASN), has announced its conditional authorisation for EDF to commission and use the Flamanville 3 reactor pressure vessel. The EPR is under construction in Normandy, northern France.

Flamanville (Image: EDF)

The authorisation is based on the regulator's October 2017 final opinion that the mechanical properties of the vessel head and bottom head of the Flamanville 3 EPR reactor pressure vessel are adequate and are therefore serviceable. This followed the discovery in 2015 by Areva NP of an anomaly in the composition of the steel in certain zones of the reactor pressure vessel's closure head and bottom head. The engineering group initiated a test programme to demonstrate that the mechanical strength of the steel is sufficient in all operating situations, including accident situations. Its conclusions were sent to ASN in December 2016.

The ASN's draft decision was opened to public comment from 3-21 September 2018, receiving over 500 contributions.

ASN on 9 October issued its authorisation for the commissioning and use of the vessel, subject to the implementation of a thermal aging monitoring test programme and on specific controls during the operation. The authorisation is only for the vessel and not the closure head, which ASN says must not be used beyond 2024.

Manufacturing operations at Framatome's Le Creusot forge, where the components were made, were suspended in December 2015 and resumed in January this year after the implementation of an improvement plan.

Researched and written by World Nuclear News