250W@4.5K氦制冷机故障模式、效应及危害度分析

Failure modes,effects and criticality analysis of a 250W@4.5K helium refrigerator

为了评估中国科学院理化技术研究所研制的一台250 W@4.5 K氦制冷机的可靠性,建立了250 W@4.5 K氦制冷机的故障模式、效应及危害度(FMECA)模型。收集了国内相似制冷机用户的低温设备失效数据,利用寿命数据软件Weibull拟合了失效数据分布,从而获得低温部件的失效率。采用了国际热核试验反应堆组织(ITER)的FMECA评价准则,分析了制冷机主要部件的故障模式及其对制冷机相关功能的影响,找出了危害度较大的关键零部件。提出了改进措施,将高风险的故障模式降低到了中低风险。

To evaluate reliability of a 250 W@ 4.5 K helium refrigerator developed in Technical Institu- te of Physics and Chemistry, Chinese Academy of Sciences, a failure modes, effects and criticality model （FMECA） was proposed. The cryogenic components failure data of similar refrigerators in China were collected and failure rate distributions were fitted with software Weibull. Hence,the failure probability of cryogenic components can be gotten. The FMECA rating scale of ITER was adopted. The failure modes of main components of this refrigerator and their effects on the related function were analyzed. The key components with high and medium risks were pointed out. The mitigation actions were proposed to decrease the major/ medium risks to medium/minor risks.