Doryokuro Kakunenryo Kaihatsu Jigyodan

Fujikura Limited

Japan Nuclear Cycle Development Institute

Nisco Kabushiki Kaisha

Mitsuru Kamei

Masataka Mochizuki

Ryuichi Okiai

Hiroshi Rindo

Hirohide Kobayashi

Tomihiro Fukada

Motoharu Yatsuhashi

Uno Osamu

Ogawa Toru

Ishii Yoichiro

Takao Sakai

Satomi Masahiro

Satoshi Mikami

Shinichi Sugihara

A dose distribution-measuring method capable of grasping a three-dimensional form of an object to be measured or evaluating a three-dimensional dose distribution thereof. The method comprises providing a multiple-eye type radiation meter probe in which at least two directional radiation detectors are arranged so as to be spaced from each other and directed toward a point to be measured; and carrying out dose measurement by directing the radiation meter probe toward an object to be measured from different positions to thereby determine a three-dimensional dose distribution of the object to be measured. Each of the radiation detectors has a structure in which a periphery of the radiation detector main body, except for a detection surface thereof, is surrounded by a radiation shield to reduce the effect of radiation from other than the object to be measured and from Compton scattering.

Multiple-eye type dose distribution measuring method

Herein disclosed is a dual-tube heat pipe type heat exchanger comprising a heat pipe confined with a working fluid for transferring a heat as a latent heat by repeating evaporations and condensations. The heat pipe includes an outer tube which is disposed within a hot fluid such that its axis is generally horizontal. Further included is an inner tube which is inserted in the outer tube and radially offset upward to substantially contact with the top portion of the inner face of the outer tube and to confine a space between the inner circumference of the outer tube and the outer circumference of the inner tube, thus forming the heat pipe.

Dual-tube heat pipe type heat exchanger

A double-cylinder selector valve for detecting and locating failed nuclear fuel assemblies including a fixed outer cylinder provided on the circumferential wall surface thereof with a plurality of outer sampling holes arranged in a grid in both the longitudinal and circumferential directions, and a movable inner cylinder disposed rotatably within the fixed outer cylinder and provided on the circumferential wall surface thereof with a plurality of inner sampling holes. Each of coolant sampling pipes extending from the coolant outlets of each of a plurality of nuclear fuel assemblies is connected to one of the outer sampling holes. The inner sampling holes communicate with some of the plurality of outer sampling holes in the fixed outer cylinder at one position of the movable inner cylinder and with others of the outer sampling holes at other positions of the movable inner cylinder. During one complete rotation of the movable inner cylinder, each of the outer sampling holes can communicate at least once with any of the inner sampling holes.

Double-cylinder selector valve for detecting and locating failed nuclear

A pressure measuring apparatus using process transmission media and comprising measuring and compensation systems. These systems have the substantially same construction which comprises a pressure receiving portion, a pressure transmitting portion and a pressure detecting portion. The pressure transmitting portion is divided into two sections, each of them contains a liquid NaK and a heat-resisting inert liquid, respectively, as pressure transmission media. A pressure of a fluid to be measured which is introduced into the pressure receiving portion of the measuring system is transmitted through the transmitting portion to the pressure detecting portion where the pressure is detected. A pressure of a gas introduced into the pressure receiving portion of the compensation system is detected in the pressure detecting portion of the compensation system in a same manner. The temperature compensation is conducted by subtracting a detected pressure in the compensation system from that in the measuring system.

Pressure measuring apparatus with temperature compensating means

An apparatus for detection of the level of a liquid metal is disclosed. The apparatus has a liquid level detecting probe provided with an exciting coil wound in a closed bottom non-magnetic sheath over the approximately whole length thereof, a level detecting coil wound in the sheath in an upper part thereof, and a temperature compensating coil wound in the sheath in a lower part thereof; a temperature control for maintaining the coils at a constant temperature; a drive circuit for supplying the exciting coil with an alternating current of a determined frequency and amplitude; and a signal processing circuit for subjecting output voltages induced in the liquid level detecting coil and in the temperature compensating coil to linear detection and then determining the ratio of the thus detected outputs, thereby detecting the level of the liquid metal. At the time of operation, the liquid level detecting probe is immersed in the liquid metal the level of which is to be detected in such a manner that the temperature compensating coil is always located below the level of the liquid metal.

Apparatus for detecting conductive liquid level

Growing community of inventors

Mito, Japan

Mitsuru Kamei