Re-fabrication and Instrumentation - resume and outlook

The special technique ''re-fabrication and instrumentation'' applied at the Institute for Energy Technology (IFE) makes further testing and measuring of irradiated fuel rods in the Halden Boiling Water Reactor (HBWR) possible. Machines, necessary for such operations, were designed and produced at IFE in the years 1991-92. Hot Lab-operations called ''re-fabrication'' include all modifications necessary to load an irradiated fuel rod, commercial or experimental, into the Halden reactor for further testing. ''Instrumentation'' includes all operations necessary to fit instruments into an irradiated fuel rod segment to measure for instance the temperature in the centreline of the fuel stack, pressure increase in the fuel rod and/or changes of the rod length during reactor experiments. The machines used are referred to as: ''Cutting and Grinding Unit'' for machining of the canning; ''Freezing and Drilling Unit'' for drilling of the centreline thermocouple hole in the active fuel stack;''Welding and Drying Unit'' a TIG welding machine for the circumferential welds and the seal welding; and a hydraulic ''Encapsulation Bench''. The ''Welding and Drilling Unit'' includes also a ''He-leak test chamber'' and a ''Hydraulic Press''. In addition, different types of PIE methods are used in quality assurance and documenting of the work done with the fuel rod. For example neutron radiography, visual inspection, dimension measurement, free volume measurements, equipment to measure the flow capability through the fuel stack and different function tests of the measuring devices. This paper will give an overview of the work done so far with this equipment and give information about new equipment which will be installed soon to deal with even more complicated test fuel designs. (Author)