关键词: ITER重力支撑, 更改设计, 真空电子束焊接, 螺栓夹紧, 屈曲

Abstract: According to the original reference design, the gravity support pedestal (GSP) of ITER toridal field magnet will be very difficult to fabricate because of large vacuum electronic welding, and therefore, two conceptual alternative designs, “split vacuum electronic welding option” and “bolt clamping option”, are put forward. The preliminary buckling analyses with FEM (finite element method) and hand calculation show that there are enough safety margin in two options and both of them are feasible. Even though the “split vacuum electronic welding option” makes the welding easier (in which GSP is split into two halves and thereby no large vacuum-chamber is needed), there are more advantages in the “bolt clamping option” (where no welding is needed), such as the GSP fabrication is simple, the reject rate is low, the cost is much lower, and the producing time is shortened. Comparably, the “bolt clamping option” is strongly recommended.

Key words: ITER gravity support, Alternative designs, Vacuum electronic welding, Bolt clamping, Buckling