A UK manufacturer of components for civil nuclear power has completed manufacturing, research and consultancy work to allow the world’s oldest working nuclear reactor to restart.
Sheffield Forgemasters International Ltd (SFIL) was contracted by plant operator, AXPO, to investigate the origin of aluminium oxide inclusions which were detected in the Reactor Pressure Vessel (RPV) of Unit 1 of the Beznau nuclear power plant (KKB) in Switzerland.
The unit was taken offline for two years until confirmed to be safe by the Swiss Federal Nuclear Safety Inspectorate (ENSI).
Forgemasters manufactured a large cylindrical forging, identical to the body of the vessel, using techniques employed in the original 1960s manufacture and also acted as engineering and metallurgical consultants, establishing a root cause and delivering reports to support the safety case, enabling the reactor to restart.
Professor Jesus Talamantes-Silva, group design and technology director at Sheffield Forgemasters International, said: “This detailed body of work provided both AXPO and ENSI with critical pieces of information, allowing them to assess the current and on-going safety of the RPV.
“Fundamental to the project was the recreation of the ultrasonic indications in the full-scale replica; this was only possible by mimicking the original manufacturing route as faithfully as possible.”
He added: “This project has enabled the Beznau reactor to restart after a very costly two-year hiatus.”
Built in 1969, the Beznau nuclear power plant is the world’s oldest nuclear power plant still in commercial operation.