考虑相关性的数控车床多因素可靠性分配法  

Multi-factor reliability allocation method of CNC lathes considering failure correlation

作　　者：王昊[1] 张义民[1] 杨周[1] 刘盼学 

机构地区：[1]东北大学机械工程与自动化学院,沈阳110819

出　　处：《哈尔滨工业大学学报》2017年第7期93-99,共7页Journal of Harbin Institute of Technology

基　　金：国家自然科学基金(51135003;U1234208);"高档数控机床与基础制造装备"科技重大专项课题(2013ZX04011-011);中央高校基本科研业务费(N150304006);辽宁省高等学校优秀人才支持计划(LJQ2014030)

摘　　要：以数控车床为研究对象,针对基于子系统间失效独立假设分配模型的不足,提出一种考虑子系统故障相关性的多因素可靠性分配方法.应用Copula理论进行故障相关性分析,建立整机可靠度函数.根据数控车床故障模式、影响及危害性分析(FMECA),对传统危害度计算公式进行修正.考虑多种分配因素建立分配矩阵,得到分配向量.将分配向量与整机可靠度函数模型将结合,得到各子系统失效率分配值.将分配方法应用到具体实例中,并将考虑不同子系统故障相关性情况的结果进行分析对比.结果表明,提出的可靠性分配方法相对于基于独立假设的分配法能够分配给各子系统更高的失效率,在降低数控车床子系统设计制造成本上具有重要意义.Taking CNC （ computerized numerical control） lathe as research object, this paper aims at drawbacks of the allocation model based on traditional failure independence hypothesis, and a multi-factor reliability allocation is proposed considering failure correlation among subsystems. Copula theory was applied to failure correlation analysis, and reliability function of CNC lathe was established. According to the failure mode effects and criticality analysis （ FMECA） , traditional computational formula of criticality was modified. Allocation matrix was established considering several allocation factors to get allocation vector, and allocation vector and reliability function of CNC lathe was combined to get failure rates of all the subsystems. The allocation method was applied to a specific example of a CNC lathe, and results were analyzed and compared considering different situations of failure correlation. It can be concluded that the allocation results of failure rate considering failure correlation are better than those based on failure independence hypothesis. Therefore, the allocation method proposed in this paper is of great significance in reducing the costs for design and manufacture of subsystems of CNC lathe.

关 键 词：数控车床 FMECA 故障相关性 COPULA 修正的危害度 可靠性分配 

分 类 号：TB114.3[理学—概率论与数理统计]