Hitachi, Ltd.

Yoshimi Ishii

Tomiharu Yoshida

Takashi Saito

Toshihiro Kodama

Tatsuyuki Omote

Noriaki Mase

Masayoshi Sasaki

Kiyoshi Izumi

Mitsuhiro Watanabe

Zunichi Sugaya

Sen Sugiyama

Isao Kouga

Seiichi Akimoto

Noriaki Hattori

A cleaning apparatus for atomic reactor control rod driving means (CRD) comprises a water tub for washing a CRD, rails laid within the water tub, a truck for loading the CRD installed on the rails, a CRD clamp unit mounted on the truck having means for rotating the CRD in the circumferential direction as well as for clamping the CRD, a CRD disassembling and assembling grapple unit installed within the water tub to clamp the CRD and move the same sideways, an outer-surface washing nozzle for washing an outer tube surface and strainer of the CRD, a lance installed within the water tub, which is insertable into the tubes of the CRD and which is equipped with a nozzle assembly to spray the washing water onto the inner surface of the tubes, a filter washing nozzle unit installed within the water tub to spray the washing water onto a cylindrical filter of the CRD, a washing-water circulating pipe connected to the water tub, and a filter unit provided on a portion of the pipe, to filter the washing water.

Cleaning apparatus for atomic reactor control rod driving means (CRD)

An apparatus for handling a control rod driving mechanism (CRD) of a nuclear reactor. The apparatus has a turn carriage provided in a space within a reactor container where a pedestal is provided, and is adapted to turn on a rail provided on the inner peripheral wall of the container. The turn carriage carries a truck adapted to run along a rail on the turn carriage. A mast is provided on the truck and is driven by a mast driving means between an upright position and a horizontal position. The mast is designed for accommodating a CRD cart. The apparatus also has a CRD mounting/demounting means secured to the mast and adapted to be moved up and down by the CRD cart such as to mount and demount the CRD in and from a CRD housing.

Apparatus for handling control rod drive

A control rod drive attaching and detaching device and a control rod drive handling device are mounted on a revolving device to be movable independently from each other. The control rod drive attaching and detaching device includes bolt handling means for loosening and tightening bolts for fastening a control rod drive to a pressure vessel of a nuclear reactor, coolant splash preventing means for disposing of coolant which flows from the control rod drive when the latter is detached from the pressure vessel, and uncoupling means for uncoupling a control rod from the control rod drive. The control rod drive handling device includes a column pivotally mounted on a carriage, a cart removably mounted on the column, and means for moving the column to a horizontal position. Each control rod drive mounted to the pressure vessel of the nuclear reactor is detached from the pressure vessel by the control rod attaching and detaching device and transferred to the cart of the control rod drive handling device. The column is moved to a horizontal position, and the cart with the control rod drive supported thereon is removed from the column.

Method of and apparatus for replacing control rod drive

Apparatus for handling control rod drives (CRD's) attached by detachable fixing means to housings mounted in a reactor pressure vessel and each coupled to one of control rods inserted in the reactor pressure vessel. The apparatus for handling the CRD's comprise cylindrical housing means, uncoupling means mounted in the housing means for uncoupling each of the control rods from the respective CRD, means mounted on the housing means for effecting attaching and detaching of the fixing means, means for supporting the housing means, and means for moving the support means longitudinally of the CRD.

Apparatus for handling control rod drives

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Hitachi, Japan

Yoshimi Ishii