Sheffield Forgemasters makes global leap in nuclear welding technology

Published: 20 February 2024

Completion of the first full-sized Small Modular Reactor (SMR) nuclear vessel demonstrator assembly at Sheffield Forgemasters has signalled a global leap in welding technology.

The company has pioneered the industrialisation of Local Electron-Beam Welding (LEBW), and complete weld-assembly of the vessel marks a pivotal moment in welding development, taking less than 24 hours to complete four, thick, nuclear-grade welds, typically requiring a year of work to complete.

With a diameter of three meters and a wall thickness of 200mm, the construction of the vessel showcases the reliability and capabilities of (LEBW), setting a dramatic new standard for weld-joining thick-walled components, previously unrivalled in a demonstrator model.

Professor Jesus Talamantes-Silva, Research, Design and Technology Director at Sheffield Forgemasters, said: “We are delighted to have reached a significant milestone in assembling a nuclear vessel demonstrator, using electron beam welding for the first time at this scale, with 100 per cent success and no defects.”

Our RD&T team deployed specially developed parameters, meticulously fine-tuned during the welding development stage, including innovative sloping-in and sloping-out techniques to start and finish the weld, ensuring a clean and complete weld join.

Sheffield Forgemasters is the only company in the UK with the capability to manufacture the large forgings required for SMRs, and it now has years of developmental lead on global competitors in welding thick-walled assemblies.

Dr Michael Blackmore, Senior Development Engineer and Project lead said: “The implication of this technology within the nuclear industry is monumental, potentially taking high-cost welding processes out of the equation.

“Not only does this reduce the need for weld-inspections, because the weld-join replicates the parent material, but it could also dramatically speed up the roll-out of SMR reactors across the UK and beyond, that’s how disruptive the LEBW breakthrough is.”

The demonstration of LEBW technology's potential opens new horizons for more efficient, low cost and less time-heavy nuclear assemblies and also has far-reaching implications for other projects which require thick-walled welded assemblies.

Dr Jacob Pope, Development Engineer and LEBW machine tool installation lead added: “We thank the Government’s Department for Energy Security and Net Zero for enabling the project through its Nuclear Innovation Program. We also thank our esteemed partner, Cambridge Vacuum Engineering, for their invaluable support throughout this endeavour. Their remote and on-site assistance played an instrumental role in the success of this milestone, highlighting the collaborative spirit that drives us forward.”