In the natural gas gathering and transportation station, bolt-gasket-flange connection (BGFC) is the main connection mode, but due to its large number, the micro-leakage may result in serious consequences. For this reason, early BGFC micro-leakage evaluation can effectively assist decision-making and prevent the occurrence of accidents. To solve the problem of insufficient field data collection, we proposed a Noisy-OR gate based fuzzy fault tree approach, and calculated the corresponding minimum cut sets and the highest risk factors. Moreover, sensitivity analysis (SA) was used to determine that material problems (wear and corrosion of the sealing surface), man-made operation problems (bolts and flanges) and working conditions (pipe vibration and temperature fluctuations) are the key factors that contributing to the BGFC micro-leakage. In brief, the combination of the fuzzy fault tree analysis and Noisy-OR gate is an effective approach for BGFC micro-leakage evaluation, which is of great significance to the micro-leakage analysis, safe operation, and risk assessment of the gas station.

在天然气集输站，螺栓-垫圈-法兰连接（BGFC）是主要的连接方式，但是由于其数量众多，微泄漏可能会导致严重的后果。因此，早期的BGFC微泄漏评估可以有效地协助决策并防止事故的发生。为了解决现场数据采集不充分的问题，我们提出了一种基于噪声或门的模糊故障树方法，​​并计算了相应的最小割集和最高风险因子。此外，使用敏感性分析（SA）确定材料问题（密封表面的磨损和腐蚀），人为操作问题（螺栓和法兰）和工作条件（管道振动和温度波动）是造成这种情况的关键因素。到BGFC微泄漏。简单来说，