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Suzuki, Sadaaki; Yagyu, Junichi; Masaki, Kei; Nishiyama, Tomokazu; Nakamura, Shigetoshi; Saeki, Hisashi; Hoshi, Ryo; Sawai, Hiroaki; Hasegawa, Koichi; Arai, Takashi; et al.
NIFS-MEMO-67, p.266 - 271, 2014/02
no abstracts in English
Shibanuma, Kiyoshi; Arai, Takashi; Hasegawa, Koichi; Hoshi, Ryo; Kamiya, Koji; Kawashima, Hisato; Kubo, Hirotaka; Masaki, Kei; Saeki, Hisashi; Sakurai, Shinji; et al.
Fusion Engineering and Design, 88(6-8), p.705 - 710, 2013/10
Times Cited Count：10 Percentile：60.97(Nuclear Science & Technology)Shibanuma, Kiyoshi; Arai, Takashi; Kawashima, Hisato; Hoshino, Katsumichi; Hoshi, Ryo; Kobayashi, Kaoru; Sawai, Hiroaki; Masaki, Kei; Sakurai, Shinji; Shibama, Yusuke; et al.
Journal of Plasma and Fusion Research SERIES, Vol.9, p.276 - 281, 2010/08
The JT-60 SA project is a combined project of JA-EU satellite tokamak program under the Broader Approach (BA) agreement and JA domestic program. Major components of JT-60SA for assembly are vacuum vessel (VV), superconducting coils (TF coils, EF coils and CS coil), in-vessel components such as divertor, thermal shield and cryostat. An assembly frame (with the dedicated cranes), which is located around the tokamak, is adopted to carry out effectively the assembly of tokamak components in the tokamak hall, independently of the facility cranes in the building. The assembly frame also provides assembly tools and jigs with jacks to support temporarily the components as well as to adjust the components at right positions. In this paper, the assembly scenario and scequence of the major components such as VV and TFC and the concept of the assembly frame including special jigs and fixtures are discussed.
Shibama, Yusuke; Arai, Takashi; Miyo, Yasuhiko; Sawai, Tomotsugu; Sakurai, Shinji; Masaki, Kei; Suzuki, Yutaka; Jitsukawa, Shiro; Miya, Naoyuki
Fusion Engineering and Design, 82(15-24), p.2462 - 2470, 2007/10
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)The structural design of the tile as a ripple reduction for toroidal magnetic field in JT-60U was outlined. 8Cr-2W-0.2V ferritic steel plates were fabricated and mechanical and vacuum properties were evaluated to assess the design conditions. Tensile properties were uniform in yield and tensile strength at ambient temperature and sufficient strength as the structural integrity at operational temperature of 423 K and 573 K. Vacuum property was measured with the baking at 473 K and similar to the conventional stainless steel but not satisfy the JT-60 standard of the in-situ material of the vacuum vessel. The ferritic steel was judged as an installable because of that the JT-60 baking temperature is 573 K higher than this test temperature of 473 K, and of that residual out-gassing was hydrogen which was the fuel of the operational plasma.
Kudo, Yusuke; Sawai, Tomotsugu; Sakurai, Shinji; Masaki, Kei; Suzuki, Yutaka; Sasajima, Tadayuki; Hayashi, Takao; Takahashi, Ryukichi*; Honda, Masao; Jitsukawa, Shiro; et al.
Journal of the Korean Physical Society, 49(96), p.S297 - S301, 2006/12
Installation of ferritic steel tiles was proposed in JT-60U to reduce the toroidal magnetic field ripple and to improve the fast ion loss, which degrades heating efficiency and increases heat load on plasma facing component under large volume plasma operations. We selected a 8Cr-2W-0.2V ferritic steel with the cost-effectiveness, in which concentration limits of activation elements in F82H were relaxed because of the less number of neutron generations from deuterium operations on JT-60U. The fabricated ferritic steel has clear tempered martensitic microstructure, and sufficient magnetic and mechanical properties. The saturated magnetization was estimated to 1.7 Tesla at 573 K, lower than expected, but effectiveness in JT-60U was confirmed by numerical analyses. To research the effect of material conditions, such as microstructure and heat treatment, on saturated magnetization of the ferritic steel based on 8-9Cr is important for the future fusion reactors which will be planned to install the ferritic steel as the in-vessel components.
Ando, Masami; Wakai, Eiichi; Sawai, Tomotsugu; Matsukawa, Shingo; Naito, Akira*; Jitsukawa, Shiro; Oka, Keiichiro*; Tanaka, Teruyuki*; Onuki, Somei*
JAERI-Review 2004-025, TIARA Annual Report 2003, p.159 - 161, 2004/11
The objectives of this study are to evaluate radiation hardening on ion-irradiated F82H up to 100 dpa and to examine the extra component of radiation hardening due to implanted helium atoms (up to 
3000 appmHe) in F82H under ratio of 0, 10, 100 appmHe/dpa.The ion-beam irradiation experiment was carried out at the TIARA facility of JAERI. Specimens were irradiated at 633 K by 10.5 MeV Fe ions with/without 1.05 MeV He ions. Micro-indentation tests were performed at loads to penetrate about 0.40 mm in the irradiated specimens using an UMIS-2000. The results are summarized as follows:1) As a result of the single irradiated F82H, the micro-hardness tended to increase about 30 dpa. 2) The extra radiation hardening was obviously caused by co-implanted helium atoms more than 1000 appm in F82H irradiated at 633 K. 3) In the dual-beam (100 appmHe/dpa) irradiated microstructure, nano-voids and fine defects were observed. It is suggested that the formation of nano-voids causes the extra radiation hardening by helium co-implantation.
Ando, Masami; Wakai, Eiichi; Sawai, Tomotsugu; Tanigawa, Hiroyasu; Furuya, Kazuyuki; Jitsukawa, Shiro; Takeuchi, Hiroshi; Oka, Keiichiro*; Onuki, Somei*; Koyama, Akira*
Journal of Nuclear Materials, 329-333(2), p.1137 - 1141, 2004/08
Times Cited Count：50 Percentile：93.75(Materials Science, Multidisciplinary)One of the most crucial issues on R&D of reduced activation ferritic/martensitic steels is the effect of helium on the degradation of fracture toughness. The synergistic effects of displacement damage and helium on F82H steel can be partially simulated by martensitic steels doped with 
B or 
Ni in a mixed spectrum fission reactor. However, the control of helium production rate is difficult and the chemical effects of B or Ni doping on mechanical property are not small. Therefore, multi-ion irradiation method is the most convenient and accurate method to simulate various irradiation conditions. Moreover, the effects of helium on irradiation hardening behavior can be examined by combining ion-irradiation with ultra micro-indentation technique. The purpose of this study is to examine the extra component of radiation hardening due to implanted helium in F82H. The extra component of irradiation hardening due to helium was hardly detected in the dual-beam irradiation. Therefore, the effect on irradiation hardening below 630K of helium (
500 appm) was very small.
Wakai, Eiichi; Kikuchi, Kenji; Yamamoto, Shunya; Aruga, Takeo; Ando, Masami; Tanigawa, Hiroyasu; Taguchi, Tomitsugu; Sawai, Tomotsugu; Oka, Keiichiro*; Onuki, Somei*
Journal of Nuclear Materials, 318, p.267 - 273, 2003/05
Times Cited Count：70 Percentile：96.81(Materials Science, Multidisciplinary)no abstracts in English
Kambara, Toyozo; Uno, Hidero; Shoda, Katsuhiko; Hirata, Yutaka; Shoji, Tsutomu; Kohayakawa, Toru; Takayanagi, Hiroshi; Fujimura, Tsutomu; Morita, Morito; Ichihara, Masahiro; et al.
JAERI 1045, 11 Pages, 1963/03
no abstracts in English
JRR-2 Control Office; Kambara, Toyozo; Shoda, Katsuhiko; Hirata, Yutaka; Shoji, Tsutomu; Kohayakawa, Toru; Morozumi, Minoru; Kambayashi, Yuichiro; Shitomi, Hajimu; Kokanezawa, Takashi; et al.
JAERI 1027, 57 Pages, 1962/09
no abstracts in English
Kambara, Toyozo; Shoda, Katsuhiko; Hirata, Yutaka; Shoji, Tsutomu; Haginoya, Kinichi; Kohayakawa, Toru; Yamaki, Jikei; Yokota, Mitsuo; Horiki, Oichiro; Yuhara, Shunichi; et al.
JAERI 1023, 120 Pages, 1962/09
no abstracts in English
JRR-2 Operations Office; Kambara, Toyozo; Shoda, Katsuhiko; Hirata, Yutaka; Shoji, Tsutomu; Haginoya, Kinichi; Kohayakawa, Toru; Yamaki, Jikei; Yokota, Mitsuo; Horiki, Oichiro; et al.
JAERI 1024, 79 Pages, 1962/08
no abstracts in English
JRR-2 Critical Experiments Group; Kambara, Toyozo; Shoda, Katsuhiko; Hirata, Yutaka; Shoji, Tsutomu; Kohayakawa, Toru; Morozumi, Minoru; Kambayashi, Yuichiro; Shitomi, Hajimu; Kokanezawa, Takashi; et al.
JAERI 1025, 62 Pages, 1962/03
no abstracts in English
Sakurai, Shinji; Masaki, Kei; Shibama, Yusuke; Shinohara, Koji; Suzuki, Yutaka; Sasajima, Tadayuki; Morioka, Atsuhiko; Hayashi, Takao; Takahashi, Ryukichi; Sawai, Tomotsugu; et al.
no journal, ,
In order to reduce Toroidal magnetic Field (TF) ripple in JT-60U, ferritic steel (8Cr-2W-0.2V) armors were installed inside Vacuum Vessel (VV). 55 plates of 8Cr-2W-0.2V were manufactured from 2.6 ton ingots made by 20 ton vacuum induction melting. Saturated magnetization and thermal conductivity are 10-20% lower than those of F82H. Electrical resistivity and tensile properties are similar to those of F82H. 1122 carbon armors were replaced to 8Cr-2W-0.2V with reinforcement of stud nut. The absorbed beam power will be expected to increase 30%. A correction method of additional magnetic flux and field caused by 8Cr-2W-0.2V armors for magnetic probes is proposed for plasma position and shape control. Correction for flux loops is mostly good, but correcting model and program for B
probe need some improvements.
Kubo, Hirotaka; Arai, Takashi; Hasegawa, Koichi; Hoshi, Ryo*; Kawashima, Hisato; Maesaki, Yoshitaka; Masaki, Kei; Sawai, Hiroaki; Shibanuma, Kiyoshi; Tabe, Masato; et al.
no journal, ,
The JT-60SA tokamak, which is a large superconducting tokamak, needs to be assembled consistently with high precision; assembly of the JT-60SA tokamak has been studied. The absolute coordinate system for the assembly is defined on the basis of the coordinate system of the JT-60 torus hall. The origin ((x, y, z) = (0, 0, 0)) of the absolute coordinate system is defined to be the center of the VV in the plasma operation. A consistent global scenario of the assembly is studied. Assembly procedures and tools for major components such as the TFCs are studies.
Arai, Takashi; Hasegawa, Koichi; Hoshi, Ryo; Kawashima, Hisato; Kubo, Hirotaka; Masaki, Kei; Sawai, Hiroaki; Shibanuma, Kiyoshi; Tsukao, Naohiro; Yagyu, Junichi; et al.
no journal, ,
In a JT-60SA project, JT-60U is repaired to superconductivity tokamak JT-60 SA as a satellite tokamak plan by "broad approach (BA) activities towards realization of the early stage of nuclear fusion energy" who carries out by Japan-Europe cooperation. JT-60SA is built in the torus hall of a JT-60 experiment building main part after demolition of JT-60U equipment. In JT-60 SA, arrangement examination and an interference check are performed about the apparatus of the structure which becomes intricate intricately using a 3D-CAD model. A plan for the three-dimensional measuring instrument (laser tracker) which is leading-edge technology to perform position measurement is carried out. The laser tracker is highly precise as compared with the usual measuring instrument, and can make a fabrication error small as much as possible. A lecture describes position measurement together with an assembly procedure.
Hasegawa, Koichi; Arai, Takashi; Hoshi, Ryo; Masaki, Kei; Saeki, Hisashi; Sakata, Shinya; Sawai, Hiroaki; Shibanuma, Kiyoshi; Suzuki, Sadaaki; Tsukao, Naohiro; et al.
no journal, ,
JAEA pushes forward construction of superconduction tokamak (JT-60SA) as part of Broader Approach activity in cooperation with EU. JT-60SA is concentrated and highly precise with a large structure in the limited space, and it is necessary to assemble it. Therefore, from 2007, assembling examination using the 3D CAD has been performed. By this lecture introduce the examination situation of the assembling procedures such as TF coil, a vacuum vessel, cryostat, EF coil of JT-60SA.
Yagyu, Junichi; Masaki, Kei; Suzuki, Sadaaki; Nishiyama, Tomokazu; Nakamura, Shigetoshi; Saeki, Hisashi; Hoshi, Ryo; Sawai, Hiroaki; Hasegawa, Koichi; Arai, Takashi; et al.
no journal, ,
no abstracts in English
Ikeda, Kohei*; Suzuki, Tsuyoshi*; Yamashiro, Hideyuki*; Sawai, Kei*; Takemura, Fumiaki*; Kawabata, Kuniaki
no journal, ,
This paper proposed a attached algae removal ability for the wireless sensor node for the underwater observation. Basic experiments by the prototype system were reported in this paper.
Ozeki, Ryutaro*; Sekino, Kodai*; Suzuki, Tsuyoshi*; Sawai, Kei*; Takemura, Fumiaki*; Kawabata, Kuniaki; Yamashiro, Hideyuki*
no journal, ,
This paper proposed the browsing system and functions for underwater environmental data gathered by wireless sensor network. The discussions were done for the design approaches and implementation examples with gathered data.
