Abstract: Based on the analysis of intelligent manufacturing line process of butyl rubber plug，we determined the critical production process and essential parameters of the process affecting the quality of butyl rubber plug，using the statistical method of statistical process control. The quality control points were established，and the control limits of metering data and counting data at the control points were determined. Based on establishing the quality pre- analysis model，the quality pre- analysis system of butyl rubber plug was developed.

Key words: quality pre-analysis system, butyl rubber plug, statistical process control, intelligent manufacturing