Fuel Element Development - Fission Product Emitting Fuel. Dragon Project Report

Fuel inserts of the ''conventional'' type have been made incorporating special features, e.g. rounded corners as required in the case of a fuel box of high bursting pressure; and a longitudinal slot to improve contact across the fuel insert/fuel box interface under reactor operating conditions. A close study has been made of the effect of the fabrication variables on fuel insert dimensions and porosity. Measurements have been made of the dimensional changes of this type of fuel insert as a result of heat treatment, and the results have been assessed in relation to the fuel box. Joints of low permeability have been prepared by sealing fuel boxes with carbon resin cement. It was not found possible to obtain joints of sufficiently low permeability by purely mechanical sealing.