What is TF Conductor
TF magnet of tokamak is the primary part of tokamak reactor generating the toroidal field (the magnetic flux bundle in "doughnut-shape") which plays the main role to confine the plasma and maintain the equilibrium. The TF conductor will be wound into the magnet and carry the current of TF coils up to 68 kA in the superconducting state at the cryogenic condition.
- Multi-Stage Superconducting Cable and Special 316LN Stainless Steel (316LN-IG-HT) Tube
- Superconducting Cable : Nb3Sn Superconducting Strands (900 wires), OFHC Srands (522 wires) and a Central Spiral
Assembling 6 sub-cable of superconducting strands (150 wrie) and OFHC strands (87 wires) revolving around the central sprial as the axis of the last-stage cabling.
KO-DA's Responsiblity for the Procurement
- 19 CICCs in 760m length, 8 CICCs in 415m length (※ total 18 TF magnets for ITER)
5 pieces of 760m CICC and 2 pieces of 415m CICC are necessary to construct one TF Magnet
- Cost : 43.4kIUA (total : 215.0kIUA), Contribution : 20.18%
EU 20.18%, Japan 24.99%, Russia 19.32%, U.S.A 7.82%, China 7.51%
More about TF conductor
The following figure represents the CICC(Cable In Conduite Conductor) for ITER TF superconducting magnet. Being inside of a special 316LN stainless steal tube (316LN-IG-HT), this superconducting cable consists of central helium channel of metal spiral, which is to reduce a pressure drop of supercrtical He in the CICC, and 6 subcables surrounding the central channel, which is made of 150 superconducting strands and 87 pure copper wires twisted in multi-stage for cabling so that 900 superconducting and 522 copper strands are necessary for a cable
To fabricate a piece of ITER TF magnet, 5 CICCs of 768m length and 2 CICCs of 428m length are required. Now, Korea is responsible for procuring 20% of the total CICC for ITER TF magnet, which is 19 CICCs of 768m and 8 CICCs of 428m.