用于产品可靠性分析的模糊FMECA方法

Application of fuzzy FMECA in analysis of product reliability

针对产品可靠性分析过程中,由于评价因素多且故障描述语言及评判指标具有模糊性,难以给出准确有效的分析结果的问题,利用模糊综合评判方法对故障模式、影响及危害性分析方法(FMECA)进行改进。通过建立因素集、评价集、模糊因素评价矩阵、权重集等步骤,将定性评价指标予以定量化。并以电磁流量计传感器系统为例,制定故障模式、影响分析(FMEA)表格,对表中各故障模式进行模糊综合评价。依据评判结果得出各故障模式的危害等级排序,进而找到产品可靠性改进的重点。分析结果与实际情况吻合,说明该方法是能够充分利用系统模糊信息进行可靠性分析的有效方法。

During reliability analysis of products, many evaluation elements are involved and failure information and evaluation indexes are fuzzy, so it is difficult to give credible and accurate analysis results. In order to resolve this problem, the fuzzy comprehensive evaluation was introduced in failure mode effect and criticality analysis （FMECA）. Factors set, evaluation set, Judgement matrix for fuzzy factors and weights set were established to quantify the qualitative evaluation index. Taking the sensor of electromag- netic flowmeter as an example, analysis table for failure modes and effects analysis （FMEA） was established and criticalities of failure modes in the table were evaluated. According to the criticality, failure modes were ranked and emphases of reliability improvement were found. The result shows that the con- clusion is consistent with the fact, so this method is available for taking full advantage of fuzzy information of system to analyze the reliability of product.