Patent ID: 7916825

Claim:
A fuel rod suitable for use in a nuclear fuel assembly, the fuel rod comprising: a cladding tube serving as a fuel rod body; a plurality of fuel pellets stacked inside the cladding tube; an upper end plug and a lower end plug each coupled to a top portion and a bottom portion of the cladding tube, respectively, the upper end plug and the lower end plug being configured to support the plurality of fuel pellets; and an elastic compression spring inserted into the cladding tube, the elastic compression spring being disposed between the upper end plug and the fuel pellets, and configured to support the fuel pellets by elastic force, wherein the elastic compression spring is of a hollow cylindrical shape; wherein the elastic compression spring is at least partially in contact with an inner circumferential surface of the cladding tube; wherein the elastic compression spring comprises: an elastic portion including a plurality of closed-loop shaped incised portions located in a longitudinal direction in the middle of the elastic compression spring; top and bottom ends having a closed ring shape, the closed ring shape having an outer diameter smaller than an outer diameter of the elastic portion; the outer diameter of the top and bottom ends being smaller than an inner diameter of the cladding tube; and the outer diameter of the elastic portion being larger than the inner diameter of the cladding tube before insertion of the elastic compression spring into the cladding tube, wherein the elastic portion is contracted when the elastic compression spring is inserted into the cladding tube.