Product Quality Accidents Risk Analyzing Approach based on the Extended FTA and Failure Cost

Various type quality accidents occurred and reported in the field of different product in the large manufacturing companies, how to identify the root causes and rank the mitigation measures are always a puzzle for their quality and after-sales departments. Therefore, in order to improve the failure mechanism modeling ability of quality improvement methods, the extended FTA (Fault tree analysis) considering the common cause failures effect and failure cost are introduced into the risk analysis for product quality accident at the first time. Firstly, risk analysis basics for quality accident of risk formation mechanism, common cause failures and extended FTA model are defined. Secondly, quality accident risk computation model based on failure cost is presented to quantitate the risk. Thirdly, an integrated quality accident risk analysis approach is established, which includes the root causes analyzing and safety measures ranking. Finally, a case study of quality risk analysis for cooling system is carried out to verify the proposed method.