During the refuelling outage at unit 2 of Finland’s Olkiluoto NPP, two fuel assemblies with 3D-printed foreign strainers were introduced into the reactor, plant owner-operator Teollisuuden Voima Oyj (TVO) said.

These are the first officially approved 3D-printed fuel components to be introduced at a nuclear power plant. StrongHold AM guest strainers, printed with 3D technology, are manufactured by Westinghouse Electric Sweden. “We can proudly say that we are pioneers in the utilisation of new technology in nuclear power plants worldwide, said Arttu Knuutila, TVO's team procurement manager.

The StrongHold AM filters are fully manufactured through 3D printing techniques and offer enhanced capture features to prevent debris from entering the fuel assembly and potentially damaging the cladding, which could cause unplanned and expensive outages.

“This is an important milestone in our efforts to improve the reliability of boiling water reactor fuel by leveraging advances in manufacturing technology, said Dr Carina Önneby from Westinghouse, EMEA's Director of Fuel Supply.

In addition, 3D technology makes it possible to produce products at competitive prices that are difficult or even impossible to obtain.

TVO's said its own research and development function is strongly involved in the design and production of 3D prints. “The metal 3D-printed guest strainers developed in collaboration with Westinghouse Electric Sweden and OKG are a concrete example of a successful collaboration,” TVO noted.

“We are now gaining valuable user experience for metallic 3D prints, in which we will invest more in the near future. A good cooperation network with 3D actors, such as Westinghouse, plays a significant role in the introduction of the technology, Knuutila said.

Image: The first officially approved 3D-printed fuel components for NPPs have been introduced at Olkiluoto NPP in Finland (Courtesy of TVO)