The Study And Application On SPC Under Special Condition

Statistical process control is one of nucleus content in the quality management, which adopts control charts to judge and monitor whether the process is in statistical control status or not. The data obeying normal distribution in long-run mass-manufacturing can be statistically analyzed and monitored by SPC technology, which has been developed very maturational and has been widely applied in manufacturing industry. But for other product modes or data not obeying normal distribution, the application of SPC is not very maturational. The paper discusses the application of SPC under special condition. The major contents are as the follows:IAt first, Q control chart and quality-oriented statistical tolerance technique are detailedly introduced, and quality-oriented Q control chart is set up based on the combination of them.Then, individual measurements control chart based on Rayleigh distribution has been established for position error and concentricity error, and it is compared with shewhart control chart and EWMA control chart; the two kinds of control charts for skewed distribution-the (X|-) and R control charts based on weighted standard deviation and skewness correction (X|-) and R control charts are introduced and compared.Finally, the complicated data statistics and the chart drawing in the quality-oriented Q control chart, individual measurements control chart based on Rayleigh distribution and skewness correction (X|-) and R control charts are carryed out via applying the ActiveX module method to adjust the object and method of the MATLAB in the VB.