Progress of Engineering Design of CFETR Machine Assembly

The major radius of the China Fusion Engineering Test Reactor (CFETR) is 7.2 m, and its minor radius is 2.2 m, which are larger than those of the International Thermonuclear Experimental Reactor (ITER). That makes the assembly of the CFETR machine more intricate and challenging due to the assembly tool design, and their stresses are more complex when the weight of key parts/components increases, especially the assembly of the cryostat vessel, the vacuum vessel (VV), the toroidal field (TF) magnets, the poloidal field (PF) magnets, and the thermal shielding (TS). Based on the characteristics of the CFETR machine, a 45-deg assembly sector (with eight sectors in total), containing one 45-deg VV sector, two TF magnets, and one 45-deg VV TS, was designed as an assembly unit together with its assembly tooling. To improve the assembly efficiency, three working regions along the toroidal direction of the CFETR machine were designed to operate simultaneously. In addition, the assembly tools of the PF magnets and the cryostat were considered, and all of them are capable of supporting and adjusting the large CFETR machine components. Meanwhile, to improve their assembly accuracy and measurement efficiency, a laser tracker, an indoor global positioning system, and a scanner were employed in their assembly process. In addition, a metrology network was built for assembly of the CFETR machine.