摘要
High intellectual, high flexible automatic manufacturing system based on low volume production is the trend in the future, but the traditional control charts whose control limits are based on at least 20～25 subgroups of five observations each are not suitable in this environment. The paper presents variance control chart used in small batch production in which there are not sufficient observations. The control limits are set reliably without restriction of the number of samples.
High intellectual, high flexible automatic manufacturing system based on low volume production is the trend in the future, but the traditional control charts whose control limits are based on at least 20～25 subgroups of five observations each are not suitable in this environment. The paper presents variance control chart used in small batch production in which there are not sufficient observations. The control limits are set reliably without restriction of the number of samples.
基金
theCommissionofScienceandTechnologyandIndustryforNationalDefence
