Device for supplementing structural integrity of spent nuclear fuel assembly during handling

A device for supplementing structural integrity of a spent nuclear fuel assembly during handling, wherein the spent nuclear fuel assembly comprises:

• a plurality of spacer grids to support a plurality of fuel rods arranged in an axial direction in a transverse direction;
• a plurality of guide tubes fixed to the spacer grids to form a skeleton of the assembly, each of the plurality of guide tubes including a bulged portion;
• and
• a top nozzle and a bottom nozzle to support upper and lower ends of the guide tubes, respectively;
• wherein the device comprises:
• a housing provided with a plurality of free end portions elastically deformable in a radial direction, the plurality of free end portions defined by a predetermined section of a hollow cylindrical body divided by slots formed in a longitudinal direction from a tip end of one side thereof, the housing further including stopper protrusions protrudingly formed in a radial direction at the tip end of each of the free end portions configured for insertion into the bulged portion of the guide tube, a first male thread formed on an outer circumferential surface of a rear end of the cylindrical body, and a female thread formed on an inner circumferential surface of the rear end of the cylindrical body;
• a rod member having a length longer than the housing, the rod member being provided at a tip end thereof with a pressurization protrusion having an outer diameter larger than an inner diameter of the free end portions, and provided at a rear end thereof with a second male thread configured to engage with the female thread of the housing when the rod member is assembled with the housing;
• and
• fixing members configured to engage with the first male thread of the housing to secure the housing and the rod member to the top nozzle of the spent nuclear fuel assembly after the device is inserted into guide tube.