Kabushiki Kaisha Toshiba

Shigenori Shiga

Makoto Ueda

Satoko Tajima

Hideki Morishita

Ritsuo Yoshioka

Yuichi Motora

Tomonobu Sakuranaga

Munenari Yamamoto

A control rod for a nuclear reactor is composed of a center structural member, a plurality of wings each composed of a sheath member of long plate structure having a U-shaped cross section and secured to the center structural member, a front end structural member secured to a front end side of the wing in a wing inserting direction in a reactor core, a terminal end structural member secured to a terminal end side of the wing, a plurality of integral type neutron absorbing elements each having a plate structure accommodated in each of the sheaths in a row in a longitudinal direction thereof and each being formed in plate shape by integrating one or more neutron absorbing plates, and a plurality of load supporting members for supporting weights of the integral type neutron absorbing elements. A length in the sheath longitudinal direction of at least one set of the integral type neutron absorbing elements accommodated in the wing is reduced, and the reduced integral type neutron absorbing elements are supported to the U-shaped sheath by the load supporting members to thereby reduce a local load applied to the U-shaped sheath.

Control rod for nuclear reactor

A control blade for a nuclear reactor having inserted upper end structural members and inserted lower end structural members connected to a plurality of wings each in the form of a generally rectangular plate having an longitudinal axis extending in the longitudinal direction of the control blade, the wing being disposed to form a cross-shaped section of the control blade. The wings and the structural members are connected to and supported on a central connection member. Each wing or a sheath member formed within each wing is formed from a diluted alloy obtained by diluting a long-lived neutron absorber such as hafnium with a diluent such as zirconium or titanium. A plurality of neutron absorber housing holes are formed in the diluted alloy section. Specifically, if the housing holes are formed to extend in the widthwise direction of the wing, the sectional area of each housing hole formed in a portion of the control blade corresponding to the region where the subcriticality in the reactor core becomes smaller after the reactor has been shut down by fully inserting the control blade into the core is larger than that of housing holes formed in the other regions. A structure having a means to cope with swelling of the neutron absorber can be applied to the former region.

Control blade for nuclear reactor

Growing community of inventors

Fujisawa, Japan

Shigenori Shiga