Kabushiki Kaisha Toshiba

Tokyo Shibaura Denki Kabushiki Kaisha

Toshiba Energy Systems & Solutions Corporation

Hideaki Heki

Kenji Arai

Shoko Suyama

Takehiko Saito

Tadashi Narabayashi

Masaru Ukai

Kouji Hiraiwa

Mikihide Nakamaru

Shinichi Morooka

Masayuki Uchihashi

Seijiro Suzuki

Satoru Oomizu

Tsuyoshi Shimoda

Masami Enda

Hitoshi Sakai

Junzo Taguchi

Katsumi Hosaka

Hiroaki Kato

Tetsuo Morisue

Kazuo Kakiuchi

Shirou Komura

Emiko Okamura

Hajime Sato

Katsumi Kubo

There are provided a continuous fiber-reinforced silicon carbide member and the like which allow sufficient improvement in a mechanical property and environmental resistance. The continuous fiber-reinforced silicon carbide member of an embodiment is a tubular shape and has a first composite material layer and a second composite material layer. In the first composite material layer, continuous fibers of silicon carbide are combined with a matrix of silicon carbide. In the second composite material layer, continuous fibers of carbon are combined with a matrix of silicon carbide. Then, the first composite material layer and the second composite material layer are stacked.

Continuous fiber-reinforced silicon carbide member, manufacturing method thereof, and nuclear reactor structural member

A channel box in an embodiment includes a tubular portion. The tubular portion includes a first tubular layer, a second tubular layer, and an intermediate tubular layer. The first tubular layer contains silicon carbide as a major component. The second tubular layer is in parallel to and surrounds or is surrounded by the first tubular layer and contains silicon carbide fibers and silicon carbide complexed with the silicon carbide fibers. The intermediate tubular layer is disposed between the first tubular layer and the second tubular layer and contains a solid lubricant.

Channel box

The present invention is to provide a reactor core that allows a nuclear plant to continuously operate for a long term period, for example 15 years or longer, without requiring any fuel exchange, reduces the duration and number of maintenance steps involved in regular plant inspections, markedly improves plant availability and economic efficiency, and is effective in terms of nuclear nonproliferation. A plurality of fuel assemblies, themselves obtained by arranging fuel rodsand water rodsin square lattices, are arranged in a square lattice at a certain pitch. The bladesof a cross-shaped (cruciform) control rodin a cross section are inserted into four adjacent spaces formed by four fuel assembliesfacing each other. A value of 0.06 cmor greater is selected for the ratio (B/S) of the width (B) of each blade on the cruciform control rodand the surface (S) of the fuel lattice defined by the surface area of a square whose side is equal to the pitch between the fuel assemblies

Reactor core and method for operating nuclear reactor

The present invention provides a boiling water reactor nuclear power plant in which a reactor core support plate, upper grid plate, and a reactor core consisting of fuel assemblies supported by these plates are provided in the inner base portion of a nuclear reactor pressure vessel. Control rod guide tubes and a reactor core shroud are positioned over the upper grid plate, and a control rod drive mechanism is provided further above same, whereby the control rods can be inserted from above the reactor core, and natural circulation of cooling water inside the reactor can be achieved by means of a chimney effect of the control rod guide tubes. According to the above structure, there can be provided a compact and economical nuclear power plant.

Boiling water reactor nuclear power plant and its construction method

An insulating shield plate (1) divides a room of an electrolysis bath (2) into an anode chamber (13) and a cathode chamber (14). An anode (5) is disposed in the anode chamber (13), and a cathode (6), metallic waste (7) and heater (4) are disposed in the cathode chamber (14). An electrolyte (3) stored in the electrolysis bath (2) flows in a circulation path from a circulating pump (10) through a circulating line (12) and filter (11) to return the electrolysis bath (2). An exhaust gas processing device 9 is connected to the electrolysis bath (2). When a voltage is supplied to the anode (5) and cathode (6), a surface of the metallic waste (7) is charged in a positive polar to dissolve a base metal of the metallic waste (7). Further, a cylindrical anode (33) is arranged in an electrolyte (32) in an electrolysis bath (31), and a cylindrical metal (34) as a metallic waste is arranged in the cylindrical anode (33). After a bar-shape cathode (35) is arranged in the cylindrical metal (34), a DC voltage is supplied to the cylindrical anode (33) and the bar-shape cathode (35). At this time, the system may be constructed in that oxygen occurs by charging in a positive polarity an inner surface of the cylindrical metal (34) and the base metal of the cylindrical shape is dissolved.

Apparatus and method for electrochemical decontamination of radioactive

An ultrasonic cleaning device for cleaning a fuel assembly constituting an item to be cleaned, includes: a plurality of ultrasonic transducers which irradiate the outside of this item to be cleaned with ultrasonic waves from at least two directions; an ultrasonic transducer translating mechanism which moves ultrasonic transducers vertically along a support member and which is provided with a steel housing constituting an ultrasonic wave reflecting structure which reflects ultrasonic waves from ultrasonic transducers towards the item to be cleaned a feed pump arranged outside the item to be cleaned and constituting a cleaning liquid supply mechanism which supplies cleaning liquid in a pressurized condition into the interior of the item to be cleaned; and a discharge pump including a cleaning liquid discharge mechanism that discharges cleaning liquid from the cleaning liquid supply mechanism to a filter device.

Ultrasonic cleaning method and device therefor

A crawler driven vehicle is utilized in a dangerous environment and remotely controlled and operated. The crawler vehicle comprises a vehicle body, four arcuate front and rear crawler assemblies respectively attached to the bilateral sides of the vehicle body, each crawler assembly comprises a crawler formed by an endless belt and stretched over the periphery of the crawler assembly so as to exhibit arcuate surface contacting the running floor, a drive mechanism for driving the crawler assembly through a power transmission mechanism, and a steering mechanism for steering the front crawler assemblies.

Crawler vehicles

An effluent gas monitoring apparatus for detecting radioactivities in water, carbon dioxide, and rare gases recovered by introducing the radioactive effluent gas to a water recovery section, a carbon dioxide recovery section and, if necessary, a rare gas concentration section which are arranged parallel to each other. The capacities, scales and gas flow rates of the respective sections which are arranged parallel to each other may be freely selected.

Radioactive effluent gas monitoring apparatus

Disclosed is an apparatus for detecting the location of failed fuel in a reactor, the apparatus comprising means for collecting tag gas from cover gas containing tag gas at ambient temperature and enriching the collected tag gas to an analyzable concentration and tag gas analysis means for analyzing the enriched tag gas to determine the composition thereof.

Failed fuel detection and location apparatus

Growing community of inventors

Yokohama, Japan

Hideaki Heki