Development of remote pipe welding tool for divertor cassettes in JT-60SA

Hayashi, Takao; Sakurai, Shinji; Sakasai, Akira; Shibanuma, Kiyoshi; Kono, Wataru*; Onawa, Toshio*; Matsukage, Takeshi*

Fusion Engineering and Design, 101, p.180 - 185, 2015/12

https://doi.org/10.1016/j.fusengdes.2015.06.195

Remote pipe welding tool accessing from inside pipe has been newly developed for JT-60SA. Remote handling (RH) system is necessary for the maintenance and repair of in-vessel components such as lower divertor cassettes in JT-60SA. Cooling pipes, which connects between the divertor cassette and the vacuum vessel with bellows are required to be cut and welded in the vacuum vessel by RH system. The available space for RH system is very limited inside the vacuum vessel, especially around the divertor cassettes. Thus, the cooling pipes are required to be cut and weld from the inside in the vacuum vessel. The inner diameter, thickness and material of the cooling pipe are 54.2 mm, 2.8 mm and SUS316L, respectively. An upper pipe connected to the divertor cassette has a jut on the edge to fill the gap between pipes. Owing to the jut and two-times welding, the welding tool achieved the maximum allowable gap of 0.7 mm.

Research and development of radiation measuring instruments for lake,pond and river sediments, 1

Yanagizawa, Koichi; Hayashi, Toshio*; Oinuma, Masaru*; Takemori, Makoto*; Ishikawa, Takanori*; Okaya, Tomoichi*; Nishigaki, Makoto*

Shadan Hojin Butsuri Tansa Gakkai Dai-129-Kai (Heisei-25-Nendo Shuki) Gakujutsu Koenkai Koen Rombunshu, p.287 - 288, 2013/10

The development of instrument aimed at the measurement of radiation dose in the sediment of lakes, rivers and sea bed been carried out. The radiation level contained in the sediment at the bottom of lake and so on is anticipated to indicate the existence of locally high radiation spots where the diffused radioactive substance is accumulated in ponds, rivers and lakes by rainwater. The radiation dose measurement system this time is to measure -ray by dragging the detector, which is called probe, at the bottom of lakes to understand the radiation dose over wide areas. Furthermore, the measurement of resistivity value at the bottom of lakes is simultaneously dose to presume the condition of sediment.

Investigation and design of the dismantling process of irradiation capsules containing tritium, 1; Conceptual investigation and basic design

Hayashi, Kimio; Nakagawa, Tetsuya; Onose, Shoji; Ishida, Takuya; Kodaka, Hideo; Katsuyama, Kozo; Kitajima, Toshio; Takahashi, Kozo; Tsuchiya, Kunihiko; Nakamichi, Masaru; et al.

JAEA-Technology 2008-010, 68 Pages, 2008/03

JAEA-Technology-2008-010.pdf:11.31MB

In-pile functional tests of breeding blankets for fusion reactors have been planned by Japan Atomic Energy Agency (JAEA), using a test blanket module (TBM) which will be loaded in ITER. The present report describes a conceptual investigation and a basic design of the dismantling process for irradiation capsules which were used in irradiation experiments by the Japan Materials Testing Reactor (JMTR) of JAEA. In the present design, the irradiation capsule is cut by a band saw; the released tritium is recovered safely by a purge-gas system, and is consolidated into a radioactive waste form. Furthermore, adoption of the inner-box enclosing the dismantling apparatus has brought a prospect to be able to utilize an existing hot cell (beta- cell) equipped with usual wall material permeable to tritium, without extensive refurbishing of the cell. Thus, the present study has indicated the feasibility of the present dismantling process for the irradiated JMTR capsules containing tritium.

Review of JAERI activities on the IFMIF liquid lithium target in FY2004

Nakamura, Hiroo; Ida, Mizuho*; Matsuhiro, Kenjiro; Fischer, U.*; Hayashi, Takumi; Mori, Seiji*; Nakamura, Hirofumi; Nishitani, Takeo; Shimizu, Katsusuke*; Simakov, S.*; et al.

JAERI-Review 2005-005, 40 Pages, 2005/03

JAERI-Review-2005-005.pdf:3.52MB

The International Fusion Materials Irradiation Facility (IFMIF) is being jointly planned to provide an accelerator-based Deuterium-Lithium (Li) neutron source to produce intense high energy neutrons (2 MW/m) up to 200 dpa and a sufficient irradiation volume (500 cm) for testing the candidate materials and components up to about a full lifetime of their anticipated use in ITER and DEMO. To realize such a condition, 40 MeV deuteron beam with a current of 250 mA is injected into high speed liquid Li flow with a speed of 20 m/s. In target system, radioactive species such as 7Be, tritium and activated corrosion products are generated. In addition, back wall operates under severe conditions of neutron irradiation damage (about 50 dpa/y). In this paper, the thermal and thermal stress analyses, the accessibility evaluation of the IFMIF Li loop, and the tritium inventory and permeation of the IFMIF Li loop are summarized as JAERI activities on the IFMIF target system performed in FY2004.

JAERI completed performance tests of the High Temperature Engineering Test Reactor (HTTR) at 950C

Kawasaki, Kozo; Iyoku, Tatsuo; Nakazawa, Toshio; Hayashi, Hideyuki; Fujikawa, Seigo

Nihon Genshiryoku Gakkai-Shi, 46(8), P. 510, 2004/08

no abstracts in English

Irradiation experiments of the 13th-15th OGL-1 fuel assemblies

Hayashi, Kimio; Sawa, Kazuhiro; Shiratori, Tetsuo; Kikuchi, Hironobu; Fukuda, Kosaku; Kitajima, Toshio; Ito, Tadaharu; Waragai, Hyota

JAERI-Research 2000-001, p.116 - 0, 2000/01

JAERI-Research-2000-001.pdf:21.78MB

no abstracts in English

Study on TRU transmutation by LMFBRs,1; Study on FBR core concepts for TRU transmution

Yamaoka, Mitsuaki; Ishikawa, Makoto; Hayashi, Hideyuki; Wakabayashi, Toshio

PNC TN9410 91-365, 368 Pages, 1991/11

PNC-TN9410-91-365.pdf:8.03MB

A study was performed on TRU transmutation by LMFBRs. This report describes the results of the items shown below. (1) Study on a super long life core loaded with TRU. A feasibility study was performed on a super long life core loaded with TRU fuel which operates without fuel exchange during 30 years. Its advantage is that it can transmute TRU with storing it in the core during plant life time. I It was found that reactivity change and power variation due to burnup can be reduced remarkably by optimizing TRU loading amount and region. Also, it was found that a 1000 MWe core can transmute TRU of 10 ton which comes from 13 LWRs. (2) Study on a heterogeneous core loaded with TRU. The radial hderogeneous core is one of the candidate concepts for TRU transmutation because the internal blanket may be loaded with larger amount of TRU than the core fuel. It was found that the core loaded with large amount of TRU in the internal blanket can transmute TRU several times more than the homogeneous core with no significant in fluence on core characteristics. (3) Study on a method for TRU loading in a subassembly. A TRU loading method was studied where both TRU loaded fuel pins and the MOX fuel pins are arranged in a subassembly aiming at reducing the number of TRU loaded fuel pins. Results are shown with a focus on power distribution in a subassembly.

Development of the electrolytic and thermochemical hybrid hydrogen production process for FBR

Hayashi, Hideyuki; Nakagiri, Toshio; Yamaki, Tetsuya; Asano, Masaharu

no journal, , 

no abstracts in English

Development of fast measurement system of neutron emission profiles using digital signal processing technique

Ishikawa, Masao; Itoga, Toshio*; Okuji, Toshio*; Nakhostin, M.*; Baba, Mamoru*; Shinohara, Koji; Hayashi, Takao; Sukegawa, Atsuhiko; Nishitani, Takeo

no journal, , 

Line-integrated neutron emission profiles are routinely measured using Stilbene neuron detectors (SNDs) in JT-60U tokamak. Although the SND has excellent pulse shape discrimination (PSD) property between neutrons and rays, the maximum count rate is limited up to 10 cps due to its analog circuit. To overcome this issue, a digital signal processing (DSP) system using a flash ADC has been developed. In this system, anode signals from the photomultiplier of the SND are directory stored and digitized in the Flash ADC. Then, the PSD is performed using software. The DSP system has been installed in JT-60U and started to measure neutrons in deuterium experiments. As a result, it is confirmed that the DSP system is successfully measured neutron fluxes with count rate up to 10 cps.

Condition of the experimental device in JRR-3

Shimojo, Yutaka; Sakata, Mami; Hayashi, Kazuhiko; Kawana, Daichi*; Asami, Toshio*; Sugiura, Ryosuke*; Okawara, Manabu*

no journal, , 

no abstracts in English