The study focuses on the measurement of He leakage from the cooling circuits of the helium-cooled GFR (gas-cooled fast reactor). It is necessary to measure two phenomena, namely losses of He from the pipeline circuit through flange joints and the contamination of helium inside the pipeline by the diffusion of permanent gases from the external environment (i.e. against the pressure gradient). Methods for determining the tightness of flange joints according to current standards are not fully suitable for these purposes. For this reason, a self-designed apparatus was constructed in order to measure both effects at pressures up to 20 MPa and temperatures within the range from ambient values up to 400 °C. Gas chromatography with a PDHID detector was used to determine the rate of diffusion of nitrogen and other permanent gases through the flange into pure He. On the other hand, the He leakage through the piping flange joint into the external environment was measured using a gas chromatograph with a high sensitivity TCD. The issues of heat distribution within the high-pressure measuring vessel are discussed as well.

该研究的重点是测量氦冷 GFR（气冷快堆）冷却回路中的氦泄漏。有必要测量两种现象，即通过法兰接头从管道回路中损失的氦气和来自外部环境的永久性气体扩散（即逆压力梯度）对管道内氦气的污染。根据现行标准确定法兰接头紧密度的方法并不完全适用于这些目的。出于这个原因，构建了一个自行设计的设备，以测量高达 20 MPa 的压力和从环境值到 400 °C 的温度范围内的影响。使用带有 PDHID 检测器的气相色谱法来确定氮气和其他永久性气体通过法兰进入纯 He 的扩散速率。另一方面，使用具有高灵敏度 TCD 的气相色谱仪测量通过管道法兰接头泄漏到外部环境中的 He。还讨论了高压测量容器内的热分布问题。