Fuel Assembly Fabrication
The uranium pellets are stacked into rods made of a super-resistant alloy, the zircaloy. A set of these rods, rigidly kept by spacer grids, form the fuel assembly. Angra 1 and Angra 2 plants are fed with two different fuels, both of them manufactured by INB.
Each fuel assembly remains in the reactor for three cycles, that is, approximately three years. After such period, they are stored inside the plants, in the spent fuel pool.
The Angra 1 Plant (Westinghouse technology) uses 121 4-meter long fuel assemblies, each containing 235 rods rigidly positioned in a metal frame formed by 10 spacer grids, one protective grid, 20 guide tubes and 1 instrumentation tube; and two nozzles, one bottom and one top.
The Angra 2 Plant (Siemens technology) uses 193 5-meter long fuel assemblies, each containing 236 rods rigidly positioned in a metal frame formed by 9 spacer grids, one protective grid, 20 guide tubes and two nozzles, one bottom and one top.