FUEL ELEMENT OF PRESSURIZED WATER-MODERATED NUCLEAR POWER REACTOR Russian patent published in 2021 - IPC G21C1/18 G21C3/00 

FIELD: nuclear technology.

SUBSTANCE: invention relates to nuclear technology for fuel elements of a VVER 1200 reactor. The fuel element consists of a cylindrical shell sealed with lower and upper plugs, concentrically welded to the shell with an inert atmosphere inside the fuel element. The shell contains a fuel column concentrically placed in it, assembled from fuel pellets with a central hole. Moreover, the fuel column in the axial direction is pressed against the bottom plug by a spring lock, which consists of turns of the compensating group, providing the axial force of the compressed fuel column, and the turns of the fixing group, ensuring the holding of the spring lock in a certain position due to an interference fit on the inner surface of the cylindrical shell. The shell and the plugs are connected by contact-butt welding, while the length of the welded joint is from one to three thicknesses of the shell wall, and the zone of the welded joint does not protrude beyond the diameter of the original shell, and the lower plug is a collet-type element, in the lower part of which there is a shoulder of a stepped profile and a slot located in a plane on the longitudinal axis, extending to the lower end.

EFFECT: increased energy efficiency and fuel burnup while maintaining reliability and safe operation of the fuel element of a pressurized water-cooled power reactor, as well as simplified assembly process of fresh fuel assemblies.

10 cl, 11 dwg, 2 tbl