The New Nuclear Manufacturing (NNUMAN) programme undertook long-term research into innovative manufacturing techniques for the future needs of the UK nuclear industry. The programme focused on early-stage research into a range of manufacturing technologies.
The programme, managed by the Dalton Nuclear Institute at The University of Manchester and supported by the Nuclear AMRC at the University of Sheffield, has received £4 million funding from the Engineering and Physical Sciences Research Council, with the two universities committing a further £4 million, and further financial and in-kind support coming from industry.
NNUMAN addressed the fundamentals of advanced manufacturing for new reactors and the next generation of nuclear power stations. Driving progress towards new, high productivity nuclear manufacturing technologies and their transition from the laboratory to production-readiness. The programme involved a high level of academic and technical support and provided a training opportunity for a number of postdoctoral researchers to join the next generation of nuclear manufacturing scientists and engineers.
Innovative joining technologies
The strict quality standards and slow product cycle of the nuclear industry have historically limited the uptake of many innovative welding and joining technologies. The Dalton Nuclear Institute brings together expertise from The University of Manchester to advance the most promising techniques and study their microstructural effects to prove their fitness for current and future nuclear applications. Techniques investigated on the NNUMAN programme included narrow groove arc welding, electron beam and laser welding of reactor steels. Professor Mike Smith and Dr John Francis are taking these techniques forward under the auspices of the Manchester Modelling and Simulation Centre with funding from industry, RCUK and BEIS.
Advanced machining and surfacing
Future designs for large nuclear vessels and components require more efficient machining techniques for both existing and future reactor materials. The Nuclear Advanced Manufacturing Research Centre (Nuclear-AMRC) at the University of Sheffield lead the research to develop and characterise optimised cutting techniques, which include key aspects of machine dynamics. This research explored highly innovative approaches for machining very large components, for example using deep-hole drilling and using machining robots with indoor positioning systems, together with assisted machining techniques. This work is continuing at the Nuclear AMRC.
Near-net shape and engineered structures
Components such as reactor vessel nozzles and valve bodies are usually machined down from forgings, castings or billets. By producing raw parts that are closer to their final shape, manufacturers can significantly reduce material waste, cost and lead times. The Dalton Nuclear Institute continues to work on ‘near-net’ production processes for nuclear applications, including Hot Isostatic Press (HIP) techniques (currently used in aerospace, and oil and gas industries). The NNUMAN research, concentrated on developing a detailed understanding of the correlation between powder properties, manufacturing process and finished material properties. See our list of publications for results.
Advanced Nuclear Fuel
Research into improvements in fuel cladding that provide greater margin under accident conditions (Accident Tolerant Fuels) have included the investigation of use of new fuel cladding materials such as silicon carbide composite where joining provides a challenge. More generally, the design of advanced fuels tends to build on scientific discovery and new knowledge at a more fundamental level. NNUMAN addressed a number of issues in both of these areas as part of a broader portfolio of research within the UK’s Nuclear Fuel Centre of Excellence.
Underpinning materials research in NNUMAN
New manufacturing technologies can change the stress state, material and microstructural properties of components and affect their behaviour in a nuclear environment. As components in next generation reactors may be in use for over 60 years, it is vital to thoroughly understand these changes and build corresponding modelling and predictive approaches, which in turn will feed through to code case development.
The Materials Performance Centre at The University of Manchester led NNUMAN’s research in this area and performed studies and tests which underpinned all other parts of the NNUMAN programme. NNUMAN projects also made use of the advanced environmental testing facilities at The University of Manchester and the Dalton Cumbrian Facility to study the effects of radiation on the structure and performance of materials.
By acting as the research engine for nuclear manufacturing, NNUMAN is drove progress and step-change technologies up the Technology Readiness Scale. The most promising manufacturing processes developed in NNUMAN are being taken forward to prototype in the Nuclear Advanced Manufacturing Research Centre (Nuclear AMRC) and, for nuclear fuel, the National Nuclear Laboratory (NNL) so that the UK manufacturing companies can learn the benefits of the new methods and use them in the future. This will help UK companies to stay at the forefront of innovation in the sector, provide more attractive propositions to clients, and ultimately win manufacturing business in the global nuclear sector with the cost-effective production of high quality nuclear components and fuels. The industrial community built up over the 5 years of the NNUMAN programme continues to work together in the form of The NNUMAN Community. The publications from the NNUMAN programme can be viewed here. The last of the PhD students supported by the NNUMAN programme will complete in April 2019.