【作者】 刘笑男；

【导师】 牛占文；

【作者基本信息】 天津大学 ， 工业工程， 2008， 硕士

【摘要】 本文综述了小批量生产方式的特点和多品种小批量生产方式下SPC(Statistical Process Control:统计过程控制)应用的动态,指出应用常规控制图理论的SPC系统不适用于多品种小批量生产,可能出现控制图无法建立或者检出力偏低等问题。并分析了通用控制图的特点及优势以及应用通用控制图解决小批量生产中样本数量不足的问题。针对微小偏差SPC中应用常规控制图检出力偏低的问题,提出应用累积和控制图(Cumulative-Sum:CUSUM)和指数加权移动平均控制图(Exponentially Weighted Moving-Averages:EWMA)加以解决。之后分别分析了累积和控制图和指数加权移动平均控制图的原理、设计方法,并用实例与常规控制图进行了分析比较,例证了累积和控制图和指数加权移动平均控制图针对微小偏差SPC的灵敏性。讨论了通用控制图中的标准变换应用于累积和控制图与指数加权移动平均控制图的可行性,并举例进行了说明。比较了累积和控制图和指数加权移动平均控制图的细微差别,指出累积和控制图对一倍至一点五倍标准差的偏差反映较灵敏,指数加权移动平均控制图针对一倍标准差以内的偏差反应较灵敏,从而提出将通用控制图、累积和控制图、指数加权移动平均控制图相结合的方法,以分别针对三倍标准差以上的偏差及小偏差的面向小批量生产方式的SPC方法。总结出面向多品种小批量微小偏差的SPC方法步骤,并且用实例证明了结合的可行性。利用IDEF0建模工具建立了以质量统计及分析为主要模块的生产过程管理系统模型,分析了系统中质量统计及分析模块及系统功能。最后对全文研究内容进行了总结,并提出进一步研究和探索的建议。更多还原

【Abstract】 In this paper, the characteristics of small batch production are illustrated. The application status of statistical process control (SPC) on this production method is summarized. Base on these analyses, it is concluded that the traditional control chart is not suitable for the SPC of small batch production, some problems like setup difficulties or relatively insensitivity to small shifts can happen. The universal control chart is put forward to solve the problem of lower quantity of samples with the analysis of the characteristics of the universal control chart.Base on the analysis of small-shift quality control using traditional control chart, the defects of lower checkout rate are illustrated, so the CUSUM control chart and EWMA control chart are put forward. The principles and techniques of the CUSUM and EWMA are illustrated separately both in theory and example. The conclusion is that the CUSUM and EWMA are two very effective alternatives to the traditional control chart may be used when detecting small shifts. The feasibility of applying standard transportation into the CUSUM and EWMA is discussed both in theory and example. With the compare of CUSUM and EWMA, it is found that the CUSUM is more sensitive to the shifts between 1 and 1.5 deviations, while the EWMA is more sensitive to the shifts lower than 1 deviation, then a combined SPC method of universal control chart and CUSUM control chart and EWMA control chart are put forward to solve these problems which is also illustrated theoretically and validated by case study. The steps of using the combined SPC are concluded. A production process management system with a master module of quality statistics and analysis is formed and illustrated using IDEF0 model-forming method. The module of quality statistics and analysis is illustrated while the function of this system is explained.At last, the conclusions of this paper are given; the further research and investigation are suggested.更多还原