动态多工位车身串并联混合装配系统可靠性评估研究

Reliability evaluation of auto body multi-station series-parallel hybrid assembly system

针对当前车身装配系统可靠性评估体系对偏差因素、可靠性要素间的相关性、过程衰退等方面的评价不完备的问题,对定位销定位偏差源的组成结构、结合来料零件定位孔、槽的尺寸质量和定位销本身定位能力水平的定位销磨损模型进行了研究。分析了系统要素可靠性间的相关性,根据Copula连接函数理论建立了相关性模型;对产品上所有关键产品特性(KPC)点在整体产品尺寸质量可靠性中所占权重进行了分配并建模,基于来料-产出流思想对串并联混合系统进行了简化,最终提出了一种综合考虑各偏差源动态输入的动态多工位车身串并联混合装配系统可靠性评估模型;利用此模型对车身某分总成装配系统进行了制造成本优化分配,并且给出了一套动周期预防性维护策略。研究结果表明:该可靠性模型精确度较高,适用于指导生产制造成本的优化和建立预防性维护策略。

Aiming at the problem of auto body reliability incomplete evaluation for deviation factors, correlation between reliability factors, process decline, the structure of locating pin deviation source were studied. The locating pin wear model was established according to the dimension of the locating hole, the size and quality of the slot and the positioning ability of the positioning pin. The correlation between the reliability of system elements was analyzed. According to the theory of Copula function, the correlation model was established.Consider the reliability of all KPC points on the product, the weight of the whole product quality reliability was assigned, and the quality reliability of the product was modeled by combining the weight and the quality reliability of a single KPC point. The idea of material incoming-output flow was proposed to simplify the series parallel hybrid system.Finally,a reliability evaluation model of dynamic multi station body serial and parallel hybrid assembly system considering dynamic input of each deviation source was proposed. Taking an assembly system for a car body as an example, the manufacturing cost was optimized based on the proposed reliability model, and a preventive maintenance strategy was presented.The results indicate that the reliability model has a high accuracy and can be used to guide the optimization of manufacturing cost and to contribute preventive maintenance strategy.