Abstract: According to the leak testing requirements defined in the ITER vacuum handbook, the leak testing scheme for the gas fueling manifold of ITER gas injection system during the on-site assembly was proposed. The inner pipes of the gas injection manifold are leak tested by helium spraying method. According to the welding sequence of the port cell, it will be implemented when the welding work of a pipe in each port cell is finished. The maximum pumping time and response time required by the inner pipe leak testing are estimated and results show that maximum pumping time is less than 30 min and response time is less than 10 min for single leak test. The guard pipe of the gas fueling manifold is leak tested by helium sniffing method, which is implemented after all the welding work of the guard pipe is finished.

Key words: Gas fueling manifold, On-site assembly, Leak testing, Helium spraying, Helium sniffing

摘要： 根据ITER设计真空手册泄漏检测的要求，提出了ITER气体注入系统汇集管道在现场安装阶段的检漏方案。对汇集管道内管的检漏采用真空氦喷吹法进行，按照窗口小室的焊接顺序，每完成一个窗口小室内的焊接就进行一次检漏。对内管检漏所需要的最长抽气时间和最长反应时间进行了评估。结果表明，单次检漏的抽气时间在30min以内，检漏的反应时间在10min以内。对汇集管道包容管的检漏采用正压氦吸枪法进行，在包容管所有焊接均完成后一次性进行检漏。

关键词: 汇集管道, 现场安装, 泄漏检测, 氦喷吹法, 氦吸枪法