NUCLEAR REACTOR FUEL ASSEMBLY

摘要

nuclear reactors. SUBSTANCE: fuel assembly has fuel element bundle 1 installed in hexahedral frame of spacer grids 2 on tubular channels 3 held in position together with fuel elements 1 by means of bottom plugs in bottom grid 4. Fuel assembly has also bottom nozzle 5 joined to bottom grid 4 by means of adapters 6 secured at its corners, top nozzle 7, and members fastening fuel elements in spacer-grid cells made in them in the form of internal projections. Each spacer grid 2 of frame is provided with second spacer grid mounted for displacement relative to the latter. Internal projections in cells of second spacer grids are disposed in opposition in their upper parts. Rim is provided for coaxial fixation of spacer grids. EFFECT: enhanced quality, extended service life, and reduced manufacturing cost of fuel assembly. 4 dwg