Conceptual Design of Robust Shielded Box Transport Container Type B(U) Package design

In recent years, a number of the organisations responsible for managing the clean-up of the UK’s nuclear sites have adopted Robust Shielded Boxes (RSBs) for the packaging of higher activity waste (HAW). RSBs are thick-walled, ductile cast iron containers with a gross mass of up to 35 tonnes. They do not require remote handling and can use unshielded, personnel-accessible stores.This paper focuses on the conceptual design of a reusable Type B(U) transport container for transport of RBSs. It presents the conceptual design development work, including the principal design features, options considered and the final conceptual design of Robust Shielded Box Transport Container (RSBTC).To allow unrestricted transport upon the UK rail network the RSBTC design is required to be compatible with the mass and dimensional limits of the most constraining W6a rail gauge. Challenges were experienced in achieving this target due to the physical size of the RSBs and high payload mass of 35 tonnes, which represents a contents mass to RSBTC gross mass ratio of over one. These requirements presented significant challenges for the lid closure and impact limiter designs, requiring the inclusion of a high-capacity bolting arrangement and novel lid features to maintain containment and structural integrity in regulatory impact scenarios.The RSBTC design has been developed to a conceptual level of detail and successfully demonstrates concept feasibility of a Type B(U) package, suitable for transport of the specified RSB maximum dimensions and maximum gross mass, within the mass and dimensional constraints of the UK rail network.Two further papers relating to the RSBTC are also proposed for PATRAM 2019. One presents a summary of the need for an RSBTC in the UK, setting out the key requirements and constraints that the design needs to satisfy, and discussing the potential benefits and applications. The second paper discusses the work carried out to design the transport container to satisfy the impact performance requirements defined in the transport regulations, including the development of the novel double-spigot lid-body interface arrangement and the impact limiting system, as well as the analyses undertaken to optimise the design and substantiate the performance.