Abstract: In a nuclear reactor fuel assembly, a relatively flexible mounting member for mounting a large coolant conducting tube to the lower tie plate whereby excessive side forces on the fuel rod spacers are avoided in the event of lateral displacement of the fuel assembly such as during a seismic event.

Abstract: A flow channel-to-nozzle attachment for a nuclear fuel assembly wherein the flow channel and nozzle are formed of material having different thermal coefficients of expansion, the attachment comprising tapered bars secured to the lower inner ends of the channel which bars are fitted into similarly tapered grooves in the adjacent outer surfaces of the nozzle, the angle of taper being selected such that the tapered bars move more or less deeply into the grooves in the nozzle with temperature changes without bending or stressing the lower end of the channel.

Abstract: In a nuclear fuel assembly having a coolant conducting or water tube which also retains the spacers in axial position, the fuel rods experience greater axial growth with exposure than the water tube creating a risk that the water tube might become disengaged from the supporting tie plates. An arrangement for preventing such disengagement is described including lengthened end plug shanks for the water tube, a protective boss surrounding the lower end plug shank to protect it from flow induced vibration, a conical seat for the lower end plug and an arrangement for limiting upward movement of the water tube.