10kW@20K氦制冷机故障树模型及可靠性分析

Fault tree model of a 10kW@20K helium refrigerator and reliability analysis

研制了一台10k W@20K氦制冷机。为评估该制冷机的可靠性,建立了10k W@20K氦制冷机的故障树模型。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,利用可靠性分析软件Block Sim计算了故障树的顶事件发生概率。通过故障树底事件概率重要度分析,得出主要影响10k W@20K氦制冷机长期可靠性的关键设备是压缩机,透平等设备,并提出了提高氦制冷机可靠性的改进措施。

A 10kW@ 20K helium refrigerator was established in the Technical Institute of Physics and Chemistry, CAS. This refrigerator was accepted technically. To evaluate this refrigerator＇s reliability, a fault tree model of this 10kW@ 20K helium refrigerator was proposed. The cryogenic components＇failure data of similar refrigerators in China were collected and which failure rate distributions were fitted with software Weibull. The occurrence probability of the top event of this fault tree model was calculated with software BlockSim. Probability importance analysis of the bottom events shows that the compressors and the turbine are the key components which have the greatest effect on the whole refrigerator＇s reliability within 5 years. The mitigation actions to improve the refrigerator＇s reliability were proposed.