Abstract: Based on former researches, traditional Statistical Process Control(SPC)model was expanded, and equipment maintenance thought was integrated. In joint economic model, three different conditions in production process were considered. Control chart was adopted to monitor the state of each condition, and Taguchi　s loss function was used to define the quality loss cost of specific state. According to the state of production process, corresponding maintenance strategy was initiated to the equipments. The quality cost and maintenance cost of process were included in total production cost. Thus, the optimal parameter designs of control chart, the sampling inspection interval, and the sample number as well as sample size taken before maintenance were obtained, so as to minimizing the total expected production cost in production cycle. The deliverable results of model could help production personnel make scientific plans and policies based on specific production conditions. The pattern research method was applied to solve the model, and the solving process was realized through tool box of MATLAB. A case study and sensitivity analysis were used to demonstrate the effectiveness of proposed model.

Key words: statistical process control, equipment maintenance policy, control chart, quality loss function, minimization of expected production cost

摘要： 在已有研究的基础上，对传统的统计过程控制模型进行拓展，融合了设备维护的思想，给出了联合经济模型。该模型考虑了生产过程出现的三种情况，运用控制图监视每种情况的生产状态，通过田口质量损失函数定义相应状态的质量损失成本，并根据过程所处的生产状态对其实施相应的维护策略。过程产生的质量成本与维护成本计入总生产成本，以获得最优的控制图界限系数、抽样检验间隔、实施计划维护前需要的样本数量及样本大小，使得生产过程在生产周期内的总期望生产成本最小。模型结果有助于生产人员根据特定的生产过程情况做出科学经济的生产计划和决策。采用单纯型搜索法对模型进行求解，求解过程通过MATLAB工具箱实现，通过数值例子和参数敏感度分析说明了该模型的有效性。

关键词: 统计过程控制, 设备维护策略, 控制图, 质量损失函数, 期望成本最小