Atomic reactor control rods and making method thereof

• Main Authors: ISHISATO SHINICHI, TASHIMA TOMOKO, UEDA SEI
• Format: Patent
• Language: English
• Published: 03.12.2003
• Edition: 7
• Subjects: NUCLEAR ENGINEERING; NUCLEAR PHYSICS; NUCLEAR REACTORS; PHYSICS

There is provided a reactor control rod which is capable of suppressing an excessive frictional force acting on passive state oxide films formed on the surfaces of neutron absorber elements, and also reducing the possibility to cause electrochemical problems, and a method of manufacturing the same. The reactor control rod comprises a wing having a sheath which has a substantially U-shaped cross-section. A top end structure is secured to a longitudinal top end of the sheath. A bottom end structure is secured to a longitudinal bottom end of the sheath. An opening portion of the sheath is secured to a central structure. A neutron absorber element is made of neutron absorbing material. The neutron absorber element is charged in the sheath. A supporting rod through hole is formed in the neutron absorber element, so as to penetrate the neutron absorber element. A supporting rod fitting hole is formed in the sheath. A load supporting rod is inserted into the supporting rod through hole. The load supporting rod has a top end portion and a main body portion. The top end portion is inserted into the supporting rod fitting hole, so as to support the weight of the neutron absorber element by the sheath via the load supporting rod. The main body portion has a diameter lager than that of the top end portion. A step is formed by a difference in diameters between the top end portion and the main body portion, so as to create a minute clearance between the sheath and the neutron absorber element.