METHOD FOR MANUFACTURING NUCLEAR REACTOR FUEL ASSEMBLY SPACER GRID Russian patent published in 2008 - IPC G21C3/34 G21C21/00 

FIELD: nuclear power engineering; manufacturing fuel assemblies for nuclear power reactors.

SUBSTANCE: spacer grid subchannels are tightly disposed in rim without forming gaps between assembled subchannel field and rim; pre-welding assembly of subchannel field is conducted in conductor using multiple-cam chuck; spacer grid subchannels are installed between conductor platform pins on its horizontal surface so that platform pins are disposed in space between subchannels and conductor stepped jaws and set apart; after that conductor stepped jaws are brought together to compress bottom part of subchannel field by projections of stepped jaws; rim is fitted into space formed between top part of subchannel field and vertical surfaces of conductor stepped jaws while holding it on horizontal surfaces of stepped jaws, then the latter are set apart again and rim is rammed until conductor platform is set down; subchannels are locked together and with rim and are extracted in this condition from conductor, whereupon they are transferred to welding position; after welding and heat treatment spacer grid is subjected to comprehensive inspections.

EFFECT: improved quality of spacer grids produced using proposed method.

1 cl, 6 dwg