Abstract
As the first step of inspection of the applicability of the PRODIA Code for dismantling activities in the decommissioning of FUGEN, manpower needs for dismantling activities in FUGEN conducted in 2008 were calculated with conventional calculation formulas developed from the data obtained from the JPDR decommissioning program. In this inspection, it was found that the actual data for the dismantling of feedwater heaters show the following two characteristic profiles: 1) the actual data were significantly smaller than the results of the conventional calculation formulas and 2) the actual data for the dismantling of the 3rd feedwater heater were two times larger than those for the dismantling of the 4th one, although both data were almost of the same weight. In order to use the PRODIA Code for further dismantling activities in the decommissioning of FUGEN, the origin of these results was investigated. This investigation showed that both of the differences in the work description between FUGEN and JPDR and between the 3rd feedwater heater of FUGEN and the 4th one produce these characteristic profiles. Since this means that the conventional calculation formula for the dismantling of feedwater heaters has no applicability, it was considered necessary to construct a new calculation formula reflecting the work description of the dismantling of feedwater heaters in FUGEN. It was found that the calculation results with this new formula showed good agreement with the actual data of both the 3rd and 4th feedwater heaters. Based on these findings, some case studies for the dismantling of feedwater heaters were conducted.
