Fabrication Design, Qualification and Key Technologies of ITER Gravity Supports
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摘要: 重力支撑(GS)作为国际热核聚变实验堆(ITER)磁体支撑系统的关键部件,不但要承受环向场超导磁体净重以及交变的电磁载荷,同时还需隔离来自杜瓦环的热量以维持环向场超导线圈的热稳定性。本文通过有限元分析和工程测试验证了GS结构设计的可靠性;通过换热分析和真空热交换效率测试验证了热锚连接结构的可靠性;通过全尺寸螺栓77 K疲劳测试验证了螺栓原型件的疲劳性能。在随后的制造过程中,使用液压拉伸器和研制的高精度螺栓伸长量测量装置对所有的螺栓进行了均匀、精确地紧固。真空正压氦检漏的测试结果证明了GS的泄漏率远低于ITER的要求。基于以上工程测试的结果,本文设计的GS的结构是可行的且能运用于ITER装置中。Abstract: As a key component of the ITER magnet supports, the ITER gravity support (GS) serves not only to bear the weight of the toroidal field (TF) coil superconductor and the alternate electromagnetic force but also to interrupt the heat from the cryostat ring and to ensure the superconductive state of the TF coils. In this paper, the fabrication design of the GS was simulated and verified via the prototype engineering test. The fatigue performance of the 718 studs was qualified by the 77 K prototype fatigue test. The design of the thermal anchor structure was characterized by the heat exchange test which carried out in a vacuum chamber. Subsequently, based on the fabrication design, the hydraulic tensors and the bespoke high precision bolt elongation measuring device were employed to fasten all the studs accurately. Finally, the results of the leakage test in the vacuum chamber indicated that the leakage rate of GS is much lower than that of ITER requirement. Based on the above work, the fabrication design is feasible and can be utilized in the manufacturing of ITER GS.
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表 1 ITER GS极端载荷工况[3]
Table 1. Load Combination Cases for ITER GS
工况 Ux/mm Fy/kN Fz/kN Mx/(kN·m) My/(kN·m) Mz/(kN·m) 1 −31 34 −1741 −1264 −1467 540 2 −31 1132 −2834 −94 −991 467 3 −31 223 740 −864 −1056 355 4 −31 231 1281 −661 −791 271 Ux—X方向的位移载荷;Fy、Fz—Y、Z方向上的力载荷;Mx、My、Mz—X、Y、Z方向上的力矩载荷 -
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