Hefei's CRAFT project has just set a record in fusion engineering with the delivery of the world's largest toroidal field (TF) coil case at the Comprehensive Research Facility for Fusion Technology in east China's Anhui Province. This 21-meter-long, 12-meter-wide steel structure tips the scales at 400 tonnes—double the weight of its International Thermonuclear Experimental Reactor (ITER) counterpart and 1.2 times larger overall.
The TF coil case plays a starring role in a tokamak reactor's magnet system. Made from cryogenic austenitic stainless steels 316LN and 316LMn, it protects and supports the superconducting coil windings that generate magnetic fields strong enough to confine plasma at temperatures hotter than the sun. It also anchors poloidal field coils that help shape and stabilize the plasma ring.
- Dimensions: 21 m × 12 m
- Weight: 400 tonnes (twice ITER's size)
- Materials: Stainless steels 316LN & 316LMn
This milestone is more than an engineering marvel—it's a leap toward commercial fusion power. With the largest TF coil case ever built, the CRAFT facility aims to push the boundaries of high-field magnet testing. Engineers will soon install the case into the tokamak vessel, cool it to cryogenic temperatures, and begin experiments to fine-tune magnetic confinement and efficiency.
Beyond fusion labs, the precision welding, machining and material science breakthroughs behind this coil case are poised to benefit aerospace, energy equipment and marine engineering. Startups and tech innovators can tap into these advances for next-generation turbines, deep-sea vessels and lightweight, high-strength structures.
For young global citizens, entrepreneurs and sustainability advocates, Hefei's achievement is a reminder: tackling monumental challenges requires bold design, cross-disciplinary collaboration and a vision for real-world impact. As fusion technology inches closer to reality, the era of virtually limitless, clean energy draws nearer—sparked by feats like this world-record coil case.
Reference(s):
World's largest toroidal field coil case delivered in E China's Hefei
cgtn.com
