FUEL ELEMENT OF NUCLEAR POWER REACTOR AND METHOD OF MAKING SAME Russian patent published in 2015 - IPC G21C3/00 

FIELD: physics, atomic power.

SUBSTANCE: invention relates to nuclear physics, particularly to gas-filled fuel element structures for experimental, test and research reactors and methods of making same. The fuel element comprises an envelope filled with a gas of a given composition and pressure, a fuel column in the envelope and terminal elements sealed to the envelope by welded joints. Both terminal elements are connected to the envelope by welded joints made by multiple-pass electron-beam welding. At least one of the terminal elements has a cavity with an ampoule inside, the ampoule containing an inert gas of a given composition and pressure. The cavity is linked to the inner volume of the envelope, and the terminal element with the cavity has a thickness comparable with that of the wall of the envelope. The fuel element is made by first forming a cavity in the terminal element and placing an ampoule filled with a gas of a given composition and excess pressure. The ampoule is made of material with a melting point lower than that of the material of the terminal element. The fuel element is sealed by welded joints made by electron-beam welding, and the inner cavity of the envelope is filled with gas by opening the ampoule after sealing using thermal action on the terminal element.

EFFECT: obtaining a fuel element with high-quality, corrosion-resistant and low-stress joints.

3 cl, 4 dwg