The Nuclear Advanced Manufacturing Research Centre (Nuclear AMRC) is working with Sellafield Ltd to slash the cost of making future designs of waste container boxes, potentially saving hundreds of millions of pounds in decommissioning costs. The clean-up programme at Sellafield and the other sites managed by the Nuclear Decommissioning Authority (NDA) will need tens of thousands of special steel boxes over the next 30 years to safely store and dispose of hazardous waste. The current design is a standardised 3m3 stainless steel box which can be stacked for long-term storage.
Sellafield Ltd is driving a project to significantly reduce that cost, and tasked engineers at the Nuclear AMRC to help come up with solutions which could save the taxpayer hundreds of millions of pounds over the lifetime of the programme. The team are focusing on the highly corrosion-resistant duplex 2205 stainless steel, which can present significant challenges during manufacturing.
Duplex steel’s high strength also makes components difficult to machine. High residual stresses in the material can lead to changes in geometry when it’s machined or welded. To investigate new casting techniques for the top flange, the Nuclear AMRC called on the specialist expertise of AMRC Castings, which investigated whether the complex shape could instead be cast as a single item. The Nuclear AMRC’s machining group will now investigate how the cast part can be finished to the final precise specifications, while maintaining geometrical accuracy and surface integrity.
