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How are uranium dioxide pellets assembled into nuclear fuel rods?
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uranium processing
How uranium is enriched to make a nuclear weapon.
The fabrication of nuclear fuel rods from uranium dioxide involves a precise industrial process to ensure safety and efficiency.1
- Pellet Formation: Uranium dioxide powder is ground to a fine consistency and pressed into a die to form small, cylindrical pellets.1
- Sintering: These pellets are fired in a furnace at temperatures between 1,500 and 1,800 °C to create a dense, durable ceramic material.1
- Cladding: The sintered pellets are loaded into prefabricated zirconium alloy tubes, known as cladding.12
- Sealing: The tubes are filled with an inert gas and welded shut to prevent leaks, after which they undergo rigorous testing.1
- Assembly: The finished rods, or pins, are bundled together using top and bottom manifolds and spacer grids to maintain proper alignment and spacing within the final fuel assembly.1
This process is standard for light-water reactors, which are the most common type of commercial power reactor globally.12