CONTROL ROD AND CONTROL ROD CLUSTER FOR REACTOR

PROBLEM TO BE SOLVED: To prevent abrasion damage on control rods of pressurized water reactor due to interference with control rod guide tube without degrading the smooth insertion capability. SOLUTION: A control rod for a reactor has a clad 31 of which upper end is sealed with an upper plug and lower end is sealed with a lower plug 33, and a neutron absorber contained in the clad 31. The lower end plug 33 consists of an inner end part 43, an outer end part 45 of nearly bullet shape and a middle part 41 having the same diameter as the clad 31. Chrome is plated on the outer surface of the outer end part 45 formed thinner than the middle part 41 and the maximum diameter of the outer end part 45 covered with the chrome-plating 47 is almost equal to the diameter of the middle part 41.