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Completion of Helical Coils for LHD

  • S. Imagawa
  • H. Tamura
  • A. Nishimura
  • T. Satow
  • J. Yamamoto
  • O. Motojima
  • The LHD Group
  • K. Nakanishi
  • O. Honma
  • M. Sudou
  • T. Kouda
  • T. Yamagiwa
  • K. Asano
Part of the Advances in Cryogenic Engineering book series (ACRE, volume 43)

Abstract

Helical coils of LHD are large scale pool-cooled superconducting coils. In order to produce a fine magnetic surface, the accuracy of the coil position is very important. The required tolerance for manufacturing is ± 2 mm. Against large electromagnetic forces, the conductors were designed to be packed into thick cases which are supported by an outer shell structure. In order to suppress the maximum tensile stress of the conductors below the yield stress, the average compressive Youngs’ modulus of the coils should be high. We developed insulator with a high compressive modulus, and we have managed the average gaps between layers within the aimed value while winding. After winding, the top cover of the coil case should be installed without leaving the residual gaps on the coils and without deforming the accurate shape. In order to reduce the assembling gap, we have machined adjusting spacers that were inserted between the coils and the top covers. After that, we tried to diminish the assembling gaps by utilizing the shrinkage by welding.

Keywords

Electromagnetic Force Helical Coil High Stress Region Welding Force Root Face 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Reference

  1. 1.
    O. Motojima, N. Yanagi, S. Imagawa, K. Takahata, S. Yamada, A. Iwamoto, H. Chikaraishi, S. Kitagawa, R. Maekawa, S. Masuzaki, T. Mito, T. Morisaki, A. Nishimura, S. Sakakibara, S. Satoh, T. Satow, H. Tamura, S. Tanahashi, K. Watanabe, S. Yamaguchi, J. Yamamoto, M. Fujiwara, and A. Iiyoshi, Superconducting magnet design and construction of LHD, Plasma Physics and Controlled Nuclear Fusion Research 1996, Fl-CN-64/G2–4.Google Scholar
  2. 2.
    S. Imagawa, S. Masuzaki, N. Yanagi, S. Yamaguchi, T. Satow, J. Yamamoto, O. Motojima, LHD Group, K. Nakanishi, K. Uchida, T. Yamagiwa, T. Yamamoto and K. Asano, Accuracy of superconducting helical coils for LHD, Proceeding of the 19th Symposium on Fusion Technology, Lisbon, Portugal, Sep. 16–20 (1996) (to be published).Google Scholar
  3. 3.
    S. Imagawa, N. Yanagi, S. Yamaguchi, T. Satow, J. Yamamoto, O. Motojima, LHD Group, T. Senba, S. Suzuki, K. Nakanishi, K. Asano, and T. Yamagiwa, Construction of Helical Coil Winding Machine for LHD and On-site Winding, IEEE Transactions on Magnetics, Vol. 32, No. 4 (1996) 2248–2251.CrossRefGoogle Scholar
  4. 4.
    H. Tamura, S. Imagawa, A. Nishimura, J. Yamamoto and Y. Shindo, Mechanics of a composite structure of GFRP insulators and superconductors with a gap. Advances in Cryogenic Engineering 42 (1996) 197–204.Google Scholar

Copyright information

© Springer Science+Business Media New York 1998

Authors and Affiliations

  • S. Imagawa
    • 1
  • H. Tamura
    • 1
  • A. Nishimura
    • 1
  • T. Satow
    • 1
  • J. Yamamoto
    • 1
  • O. Motojima
    • 1
  • The LHD Group
  • K. Nakanishi
    • 2
  • O. Honma
    • 2
  • M. Sudou
    • 2
  • T. Kouda
    • 2
  • T. Yamagiwa
    • 2
  • K. Asano
    • 2
  1. 1.National Institute for Fusion ScienceNagoya 464-01Japan
  2. 2.Hitachi Ltd.TokyoJapan

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