Abstract: A channel box has a hollow elongated portion and accommodates a plurality of nuclear reactor fuel rods inside the hollow elongated portion, wherein the hollow elongated portion is constituted by a plurality types of silicon carbide composite materials. The channel box has a shape that can be achieved by applying the silicon carbide composite material and can increase earthquake resistance and improve functions and performance as a fuel assembly.

Abstract: A channel box has a hollow cylindrical portion and accommodates a plurality of nuclear reactor fuel rods inside the hollow cylindrical portion, wherein the hollow cylindrical portion is constituted by a plurality types of silicon carbide composite materials. The channel box has a shape that can be achieved by applying the silicon carbide composite material and can increase earthquake resistance and improve functions and performance as a fuel assembly.

Abstract: A nuclear reactor control rod with SiC fiber reinforced structure comprises wing sections and a central joint section. Each of the wing sections is a flat plate spreading axially and radially, and includes storage tubes and a wing surface structural member. The storage tubes are arranged in parallel in a flat plane and contain a neutron absorbing member containing the neutron absorbing material. The wing surface structural member is formed by molding of SiC/SiC composite material as to cover surfaces of the storage tubes and formed to have an outward shape of a flat plate. The central joint section and storage tubes are made of SiC/SiC composite material. The central joint section bundles the wing sections together at center. The storage tubes are bundled together with fibers made of SiC or a textile made of SiC.

Abstract: A reactor control rod for nuclear reactor according to an embodiment has: a plurality of wing sections arranged radially around an axis extending in vertical direction in such a way as to be spaced out each other in a circumferential direction; and a central joint section bundling the plurality of wing sections together at center, wherein at least part of the central joint section and wing surface structural member is made of SiC-fiber-reinforced SiC composite material. The wing surface structural member of side of the central joint section may be sealed with the SiC-fiber-reinforced SiC composite material. Orientation directions of SiC fibers in the SiC-fiber-reinforced SiC composite material may be such that arithmetic mean of cos2? for all SiC fibers may be ½ or greater, where ? is an angle formed of each fiber with the longitudinal direction of the wing section.

Abstract: A control rod for nuclear reactors includes four wings including neutron absorbers containing hafnium, a front end structural member which has a cross shape in cross section and includes brackets bonded to the leading ends of the wings, and a terminal end structural member which has a cross shape in cross section and includes brackets bonded to the tailing ends of the wings. The four wings are bonded to a wing-bonding member including a cross-shaped center shaft so as to form a cross shape. The front end structural member and the wing-bonding member are made of a zirconium alloy. The wings include neutron-absorbing plates having neutron-absorbing portions and each have an outer surface which is opposed to a fuel assembly and at which a hafnium-zircaloy composite member covered with zircaloy is disposed. The neutron-absorbing plates are opposed to each other with trap spaces disposed therebetween.

Abstract: A control rod for nuclear reactors includes four wings including neutron absorbers containing hafnium, a front end structural member which has a cross shape in cross section and includes brackets bonded to the leading ends of the wings, and a terminal end structural member which has a cross shape in cross section and includes brackets bonded to the tailing ends of the wings. The four wings are bonded to a wing-bonding member including a cross-shaped center shaft so as to form a cross shape. The front end structural member and the wing-bonding member are made of a zirconium alloy. The wings include neutron-absorbing plates having neutron-absorbing portions and each have an outer surface which is opposed to a fuel assembly and at which a hafnium-zircaloy composite member covered with zircaloy is disposed. The neutron-absorbing plates are opposed to each other with trap spaces disposed therebetween.

Abstract: A control rod for nuclear reactors includes four wings including neutron absorbers containing hafnium, a front end structural member which has a cross shape in cross section and includes brackets bonded to the leading ends of the wings, and a terminal end structural member which has a cross shape in cross section and includes brackets bonded to the tailing ends of the wings. The four wings are bonded to a wing-bonding member including a cross-shaped center shaft so as to form a cross shape. The front end structural member and the wing-bonding member are made of a zirconium alloy. The wings include neutron-absorbing plates having neutron-absorbing portions and each have an outer surface which is opposed to a fuel assembly and at which a hafnium-zircaloy composite member covered with zircaloy is disposed. The neutron-absorbing plates are opposed to each other with trap spaces disposed therebetween.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A control rod driving hydraulic system of a control rod driving system of a nuclear power plant, in utilization of condensate as a control rod driving water comprises a water pressure control unit arranged for each control rod and a water pressure supply unit for commonly supplying water pressure to all control rods. The water pressure supply unit comprising a pump mechanism operatively connected to a condensate supply source for driving the control rod driving water, a filter mechanism operatively connected to the condensate supply source and the pump mechanism for filtering the condensate as the control rod driving water, a valve unit for regulating quantity of flow of the control rod driving water, and a valve unit for regulating pressure thereof. The filter mechanism including at least one hollow fiber filter unit for purifying the control rod driving water. The hollow fiber filter unit includes a backwash regeneration equipment.