Fuel guide pin, fuel guide pin attachment method, core plate, and nuclear reactor

摘要

A fuel guide pin to be fixed to a core plate includes a shrink fit portion (2) which is inserted into a recessed portion (22a) having a bottom and being provided in a core support plate (22) and fixed thereto by means of shrink fit; a pin portion (3) provided above the shrink fit portion (2) and projecting from an upper surface of the core support plate (22), over which a fuel assembly to be loaded on the core support plate (22) is inserted; and a constricted portion (4) which is provided between the shrink fit portion (2) and the pin portion (3) in a constricted shape having a smaller diameter than an outer diameter of the pin portion (3) and has a lower narrowed portion (4) a smoothly narrowed toward the most constricted portion from the shrink fit portion side (2).