Patent Number: 046719261
Section: summary

TECHNICAL FIELD The present invention relates to a nuclear fuel assembly comprising a plurality of vertical fuel rods, a top tie plate which is arranged at the upper ends of the fuel rods, a fuel channel made with approximately square cross-section and surrounding said fuel rods and said top tie plate, and a fixing member of stainless steel attached to the fuel channel. PRIOR ART The top tie plate has a vertical, upwardly-extending projection provided in a corner portion of said fuel channel and being arranged in a tensile force-transmitting connection with said fixing member via a vertical bolt which is passed through a through-hole provided in said fixing member. The bolt is made of a material whose coefficient of thermal expansion is less than the coefficient of thermal expansion of said stainless steel. DISCLOSURE OF THE INVENTION The task which is to be solved through the invention is the provision of a fuel assembly of the initially mentioned type in such a way that the probability of rupture in the above-mentioned bolt is considerably reduced. According to the invention, the bolt is surrounded by a metallic sleeve which is arranged to be loaded with a compressive force corresponding to a major part of the tensile force acting on said bolt, said sleeve being made of a metallic material whose coefficient of thermal expansion is smaller than the coefficient of thermal expansion of said stainless steel.