Flamanville 3: New Reactor Vessel Head Arrives, Marking a Key Milestone Ahead of VC1
As the first periodic outage (VC1) of France’s EPR approaches, EDF is preparing for this major milestone at Flamanville 3. In addition to replacing the reactor vessel head, this first major outage will mobilise nearly 2,500 personnel and involve close to 20,000 activities over a period of 350 days.
On June 16, the new reactor vessel head for the Flamanville EPR arrived on site. “This delivery marks the concrete start of one of the flagship projects of the first periodic outage, which will begin on September 26,” EDF stated in a press release. The replacement of this component fulfils commitments made by EDF to the French Nuclear Safety and Radiation Protection Authority (ASNR).
“This outage will be unique, just like Flamanville 3 itself, with 350 days of work, several hundred regulatory inspections and major industrial operations to be carried out under unprecedented conditions,” said Cédric Lewandowski, EDF Executive Senior Vice President in charge of Nuclear and Thermal Generation, in a LinkedIn post.
Manufactured by Framatome at its Saint-Marcel facility, the reactor vessel head is more than two metres high, has a diameter of 5.75 metres and weighs nearly 100 tonnes. It performs two essential functions in reactor operation. First, it ensures the integrity of the Reactor Coolant System pressure boundary. Second, it houses the 89 control rod drive mechanisms used to safely control the nuclear chain reaction.
Its replacement will be carried out in several stages. Prior to the outage, the new vessel head will be equipped and inspected. Once VC1 begins, the control rod drive mechanisms will be transferred from the existing vessel head to the new one, followed by a series of tests. “The existing vessel head will then be stored on site for two years in a dedicated building before being transferred to an appropriate treatment facility,” EDF explained.
Preparation already well advanced
However, the VC1 outage at Flamanville 3 extends far beyond the replacement of the reactor vessel head. This first major outage following the unit’s commercial operation will provide an opportunity to perform extensive maintenance activities, detailed inspections and regulatory examinations. “Modular preparation, skills development and enhanced project management: everything is being put in place to ensure this first outage is completed under the best possible conditions,” summarised Cédric Lewandowski.
The EDF executive recently participated, alongside the project’s main industrial partners, in the VC1 steering committee. “This collective milestone is essential. It allows decisions to be aligned, challenges to be shared and the next steps to be secured,” he explained. In total, EDF expects to mobilise 2,500 personnel and 200 companies, with the number of planned activities estimated at nearly 20,000. ■