METHOD FOR MANUFACTURING FUEL ASSEMBLY SPACER GRIDS

摘要

FIELD: nuclear power engineering; spacing apart fuel elements in reactor fuel assemblies. ^ SUBSTANCE: proposed method includes insertion of auxiliary inserts in assembly field holes designed for guide channels and central tube with desired inscribed circumference in each hole prior to spot welding of subchannels to join them together in assembled field; these auxiliary inserts have same diameter as guide channel and central tube and their temperature coefficient of linear expansion equals that of subchannel material; spot welding of subchannels to each other and to rim is effected while inserts are installed and upon heat treatment these inserts are removed. ^ EFFECT: enhanced quality and yield of spacer grids. ^ 1 cl, 1 dwg