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Hamada, Takashi; Hasegawa, Shin; Fukasawa, Hideyuki*; Sawada, Shinichi; Koshikawa, Hiroshi; Miyashita, Atsumi; Maekawa, Yasunari
Journal of Materials Chemistry A, 3(42), p.20983 - 20991, 2015/11
Times Cited Count:35 Percentile:70.48(Chemistry, Physical)no abstracts in English
Shibama, Yusuke; Okano, Fuminori; Yagyu, Junichi; Kaminaga, Atsushi; Miyo, Yasuhiko; Hayakawa, Atsuro*; Sagawa, Keiich*; Mochida, Tsutomu*; Morimoto, Tamotsu*; Hamada, Takashi*; et al.
Fusion Engineering and Design, 98-99, p.1614 - 1619, 2015/10
Times Cited Count:4 Percentile:32.95(Nuclear Science & Technology)The JT-60SA vacuum vessel (150 tons) is a double wall torus structure and the maximum major radius of 5.0 m and height of 6.6 m. The manufacturing design concept is that the vessel is split in the 10 toroidal sectors manufactured at factory, and assembled on-site; seven of the 40-degree sectors, two of the 30-degree beside final one, and the final of the 20-degree. The final sector is assembled with the VV thermal shield and toroidal field magnets into the 340-degree as prepared in one sector. Sectors are temporally fitted on-site and adjusted one over the other before the assembly. After measurement of the dimensions and the reference, these sectors are transferred onto the cryostat base. First, three 80-degree sectors are manufactured with mating each 40-degree sector by direct joint welding. The rest sectors including the final sector are jointed with splice plates. Welding manipulator and its guide rails are used for these welding. In this paper, the detail of the VV sectors assembly including the final sector is explained. Welding technologies to joint the two of 40-degree sectors are reported with the present manufacturing status and the welding trial on the vertical stub with the partial mock-up of the final sector are discussed with the assembly process.
Kawano, Katsumi; Hamada, Kazuya; Okuno, Kiyoshi; Kato, Takashi
Teion Kogaku, 41(3), p.105 - 112, 2006/03
no abstracts in English
Sakasai, Akira; Ishida, Shinichi; Matsukawa, Makoto; Akino, Noboru; Ando, Toshinari*; Arai, Takashi; Ezato, Koichiro; Hamada, Kazuya; Ichige, Hisashi; Isono, Takaaki; et al.
Nuclear Fusion, 44(2), p.329 - 334, 2004/02
no abstracts in English
Sakasai, Akira; Ishida, Shinichi; Matsukawa, Makoto; Akino, Noboru; Ando, Toshinari*; Arai, Takashi; Ezato, Koichiro; Hamada, Kazuya; Ichige, Hisashi; Isono, Takaaki; et al.
Nuclear Fusion, 44(2), p.329 - 334, 2004/02
Times Cited Count:7 Percentile:22.88(Physics, Fluids & Plasmas)no abstracts in English
Arai, K.*; Ninomiya, Akira*; Ishigooka, Takeshi*; Takano, Katsutoshi*; Nakajima, Hideo; Michael, P.*; Vieira, R.*; Martovetsky, N.*; Sborchia, C.*; Alekseev, A.*; et al.
Cryogenics, 44(1), p.15 - 27, 2004/01
Times Cited Count:3 Percentile:15.45(Thermodynamics)no abstracts in English
Hamada, Kazuya; Takahashi, Yoshikazu; Matsui, Kunihiro; Kato, Takashi; Okuno, Kiyoshi
Cryogenics, 44(1), p.45 - 52, 2004/01
Times Cited Count:21 Percentile:61.01(Thermodynamics)In the ITER Central Solenoid Model Coil (CSMC) and a CS Insert Coil (CSIC) experiment, a pressure drop of the CSIC decreased by about 12% at 40 kA, 10 T and coupling losses indicated an transport current dependence. As a result of pressure drop analysis, an electromagnetic force causes a compressive deformation of cable in a jacket and a new flow passage was generated as a gap between cable and jacket. The cable deformation causes a decrease of a contact electrical resistance between strands and an increase of coupling losses. Taking account of the electromagnetic force dependency of a coupling time constant, calculated coupling losses show a good agreement with measured coupling losses at a pulsed operation of CSMC and CSIC.
Isono, Takaaki; Kawano, Katsumi; Hamada, Kazuya; Matsui, Kunihiro; Nunoya, Yoshihiko; Hara, Eiji*; Kato, Takashi; Ando, Toshinari*; Okuno, Kiyoshi; Bono, Takaaki*; et al.
Physica C, 392-396(Part2), p.1219 - 1224, 2003/10
A 60-kA high-temperature-superconductor (HTS) current lead has been fabricated and tested for aiming at the application to a fusion magnet system, providing a low heat leak current lead. The design of HTS current leads is optimized not only to reduce the heat leak but also to perform safe operation even in fault conditions. The HTS current lead consists of a forced flow cooled copper part and a conduction cooled HTS part. The HTS part is composed of 288 Ag-10at.%Au sheathed Bi-2223 tapes and they are cylindrically arrayed on a stainless steel tube. The diameter and the length of the HTS part are 146 mm and 300 mm, respectively. Operation of a 60 kA current, which is the world record, was successfully achieved at coolant of 20 K, 3.2 g/s for the copper part, and a low heat leak of 5.5 W at 4.2 K was demonstrated. This result shows that the electric power of a refrigerator to cool the current lead can be reduced by 1/3 of that in a conventional current lead. In conclusion, technology of a large HTS current lead for fusion application is established.
Hamada, Kazuya; Matsui, Kunihiro; Takahashi, Yoshikazu; Nakajima, Hideo; Kato, Takashi; CS Model Coil Test Group
Teion Kogaku, 38(8), p.417 - 424, 2003/08
As one of the R&D of ITER. a hydraulic performance of NbAl insert coil was measured and compared with other NbSn conductors. It seems that a longer twist pitch will promote a triangle helium flow space among 4th twist stage cables, jacket and center channel and contribute reduction of pressure drop. Under 500 kN/m of the electromagnetic force, the pressure drop of the NbAl insert decreased by approximately 5%. NbAl conductor indicated quit rigid characteristic under the electromagnetic force and suitable for future magnet with higher magnetic field and current.
Hamada, Kazuya; Kawano, Katsumi; Matsui, Kunihiro; Kato, Takashi; Sugimoto, Makoto; Hara, Eiji*; Okuno, Kiyoshi; Egorov, S. A.*; Rodin, I.*; Sytnikov, V. E.*; et al.
Teion Kogaku, 37(10), p.531 - 538, 2002/10
In the Engineering Design Activities of the International Thermonuclear Experimental Reactor (ITER), Toroidal Field (TF) Insert have been developed and tested successfully. In the experiment, pressure drop performance of TF insert was investigated. There were two purposes for the investigation. One is to verify the pressure drop prediction using correlations proposed by various researchers. Second is to observe a behavior of pressure drop under the electromagnetic force. The pressure drops of TF insert decreased by around 12% during current-carrying operation of 46kA at 13T. After several current-carrying operation, the friction factor of TF insert has finally reached a value which is around 12% lower than that of virgin state and was not recovered even if there were zero current. It is considered that a deformation of cable cross section inside the conductor jacket appears due to electromagnetic force and a new flow path in the jacket is generated.
Guillemet, L.*; Jager, B.*; Haange, R.*; Hamada, Kazuya; Hara, Eiji*; Kalinin, G.*; Kato, Takashi; Millet, F.*; Shatil, N.*
Proceedings of 19th International Cryogenic Engineering Conference (ICEC-19), p.105 - 108, 2002/07
Japan Atomic Energy Research Institute has designed a ITER cryoplant and cryo-distribution in the international collaboration. The ITER cryoplant that will be the largest cryogenic system for the Fusion facility in the world, is designed to be stable in operation despite the pulsed nature of heat deposition in the magnet system. The refrigeration capacity of cryoplant is 48 kW at 4.5 K of refrigeration power and 0.16 kg/s of supercritical helium supply. In the cryoplant, a supercritical helium pump and a cold compressor is applied, based on the successful achievement of cryogenic system for the ITER central solenoid model coil.
Hamada, Kazuya; Takahashi, Yoshikazu; Matsui, Kunihiro; Kato, Takashi; Okuno, Kiyoshi
Teion Kogaku, 37(6), p.257 - 264, 2002/06
no abstracts in English
Hamada, Kazuya; Nakajima, Hideo; Okuno, Kiyoshi; Endo, Sakaru*; Kikuchi, Kenichi*; Kubo, Yoshio*; Aoki, Nobuo*; Yamada, Yuichi*; Osaki, Osamu*; Sasaki, Takashi*; et al.
JAERI-Tech 2002-027, 23 Pages, 2002/03
The Engineering Design Activities (EDA) for the International Thermonuclear Experimental Reactor (ITER) was performed under the collaboration of Japan, EU, Russia and the US. The EDA was successfully completed in July 2001, in which the development of fabrication technology for advanced components, such as superconducting coils, was conducted. The ITER magnet system consists of Toroidal Field coils, a Central Solenoid (CS), Poloidal Field coils and Correction coils. The construction of these coils requires advanced technologies that fairly exceeded those available at the start of the EDA. Therefore, CS Model Coil and TF Model Coil projects were implemented. To fabricate the CS Model Coil, the fabrication technologies for high performance strand, large cable, winding, heat treatment, joint and insulation are indispensable. This report describes the above detailed fabrication technologies successfully developed in the CS Model Coil Project.
Hamada, Kazuya; Kato, Takashi; Kawano, Katsumi; Hara, Eiji*; Ando, Toshinari; Tsuji, Hiroshi; Okuno, Kiyoshi; Zanino, L.*; Savoldi, L.*
AIP Conference Proceedings 613, p.407 - 414, 2002/00
no abstracts in English
Ando, Toshinari; Kato, Takashi; Ushigusa, Kenkichi; Nishio, Satoshi; Kurihara, Ryoichi; Aoki, Isao; Hamada, Kazuya; Tsuji, Hiroshi; Hasegawa, Mitsuru*; Naito, Shuji*
Fusion Engineering and Design, 58-59, p.13 - 16, 2001/11
Times Cited Count:10 Percentile:58.96(Nuclear Science & Technology)no abstracts in English
Kato, Takashi; Tsuji, Hiroshi; Ando, Toshinari; Takahashi, Yoshikazu; Nakajima, Hideo; Sugimoto, Makoto; Isono, Takaaki; Koizumi, Norikiyo; Kawano, Katsumi; Oshikiri, Masayuki*; et al.
Fusion Engineering and Design, 56-57, p.59 - 70, 2001/10
Times Cited Count:17 Percentile:74.75(Nuclear Science & Technology)no abstracts in English
Terakado, Tsunehisa; Okano, Jun; Shimada, Katsuhiro; Miura, Yushi; Yamashita, Yoshiki*; Matsukawa, Makoto; Hosogane, Nobuyuki; Tsuji, Hiroshi; Ando, Toshinari*; Takahashi, Yoshikazu; et al.
JAERI-Tech 2001-056, 24 Pages, 2001/08
no abstracts in English
Kato, Takashi; Nakajima, Hideo; Isono, Takaaki; Hamada, Kazuya; Kawano, Katsumi; Sugimoto, Makoto; Nunoya, Yoshihiko; Koizumi, Norikiyo; Matsui, Kunihiro; Oshikiri, Masayuki*; et al.
Teion Kogaku, 36(6), p.315 - 323, 2001/06
no abstracts in English
Hamada, Kazuya; Kawano, Katsumi; Hara, Eiji*; Kato, Takashi; Shimba, Toru*; CS Model Coil Test Group
Teion Kogaku, 36(6), p.330 - 335, 2001/06
no abstracts in English
Kawano, Katsumi; Hamada, Kazuya; Matsui, Kunihiro; Hara, Eiji*; Kato, Takashi; CS Model Coil Test Group
Teion Kogaku, 36(6), p.381 - 388, 2001/06
no abstracts in English