Reactor and fuel handling on PNC prototype fast breeder reactor plant MONJU

The Design of "MONJU" protorype fast reactor succeeding to "JOYO" experimental fast reactor is carried out by P. N. C. "MONJU" plant uses a loop type configuration for the primary system and a single rotating plug-fixed arm pantograph type fuel handling mechanism for refueling system, This report presents the design and major R. D. works»

The reactor core is composed of 196 core fuel assemblies,17^ radial blanket assemblies, and 19 control assemblies including four back up shut down assemblies, surrounded by four rows of stainless steel neutron shields»

Each core fuel assembly contains 169 fuel pins; which has 900 mm length of PUO2-UO2, 350 mm long upper and lower axial blankets of depleted UO2 and fission gas reservoir located at the upper end. Each blanket fuel assembly houses 6l pins; which has 1,600 mm length of depleted UO20 B^C material is used for the control assemblies and the external shape and size of the lower guide tube are identical to those of the hexagonal fuel element housing»