Fabrication of Ebr-Ii, Core-I Fuel Pins

Abstract

A total of 11,117 enriched uranium-5 w/o fissium alloy fuel pins were manufactured for EBR-II, Core I. These were made from a synthetic fission product alloy of nonradioactive elements, natural uranium, and enriched uranium. The material was supplied as precast billets. The manufacturing methods were developed for the EBR-II Fuel Cycle Facility. Experimental refabrication equipment was used to production test both the methods and the equipment. The billets were induction melted and pressure cast into precision-bore, high-silica glass molds in batches of 90 to 160. The number of molds used was adjusted according to batch w^eight. After casting, the molds were broken away and the castings were fed into a pin-process and inspection machine. Both ends were sheared from the castings to produce finished pins measuring 0.144 in. in diameter by 14.22 in. long. The pins were inspected for diameter, porosity, weight, and length. Rejected pins and sheared ends were broken into short lengths and returned for consolidation. Acceptable fuel pins w^ere sealed and sodium bonded in stainless steel jackets, and assembled into Core-I fuel elements.

The Ebr-Ii Skull Reclamation Process. Part Iii. Skull-Oxidation Equipment.

“…Approximately 1 kW of heat is required to maintain a typical skull (400 to 1000 g) at the desired 700°C temperature. This heat is supplied by three sources: (1) fissionproduct decay heat within the skull and crucible, (2) heat produced by the exothermic oxidation reaction, and (3) supplemental electrical heating. The fission-product decay heat rate is estimated to be 0.32 kW for a typical skull, assuming absorption of 40% of the gamma activity and 100% of the beta activity.…”