Abstract The ITER gas injection system delivers gases from the tritium plant to the vacuum vessel, fueling pellet injection system, and neutral beam for plasma operation and fusion power shutdown. In this system, the gas fueling (GF) gas valve box (GVB) is an indispensable part that mainly provides functions of gas throughput control and measurement of gas pressure, flow rate, and temperature. The preliminary structure design is largely driven by the requirements of magnetic field compatibility and limited integration space. A strong magnetic field of over 0.2 T exists around the GVB locations, so a magnetic shielding design is required to ensure the normal function of susceptible components. Instead of the previous overall shielding, a local magnetic shielding has been developed by a validated analysis method. As a result, the total weight of the shield has been reduced from over 7000 kg to about 200 kg. Furthermore, considering the limited space reservation, a highly compact flat layout for the GF GVB has been developed to ensure enough maintenance space in front of it. In addition, other requirements such as structure integrity under various load combinations, leak detectability, in situ maintainability, etc., have all been taken into account.

中文翻译：

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ITER气体喷射系统气体燃料气阀箱结构设计

摘要 ITER 气体喷射系统将气体从氚装置输送到真空容器、燃料颗粒喷射系统和用于等离子体操作和聚变功率关闭的中性束。在该系统中，加气（GF）气阀箱（GVB）是必不可少的部件，主要提供气体流量控制和气体压力、流量、温度测量等功能。初步结构设计很大程度上是由磁场兼容性和有限集成空间的要求驱动的。GVB 位置周围存在超过 0.2 T 的强磁场，因此需要进行磁屏蔽设计以确保敏感元件的正常功能。代替以前的整体屏蔽，局部磁屏蔽已通过验证的分析方法开发。因此，盾牌的总重量从7000多公斤减少到200公斤左右。此外，考虑到有限的空间预留，GF GVB 开发了高度紧凑的平面布局，以确保其前面有足够的维护空间。此外，还考虑了其​​他要求，例如各种载荷组合下的结构完整性、泄漏检测性、原位可维护性等。