Fabrication of UO2 fuels with non-destructive assay and rod scanner technology for production and final quality control

The production of nuclear fuels requires a continuous in-process inspection which includes the control of equipment and process parameters as well as the quality control of the material. All components and intermediate products belonging to fuel fabrication, or being produced throughout the process, are examined by physical and chemical tests. The supervision of important process and quality parameters was improved by new techniques and instrumentations of nondestructive in-line and laboratory assays. For example the 235U enrichment is supervised by the UF6-incoming control up to a continuously working in-line instrumentation, which measures the 215U concentration in the feed hoppers before pressing. For final control of the fuel rods, an active rod scanner, which examines the rod's structure and composition, the 235U enrichment, and pellet mix-up, is used. (orig.)