Shewhart Control Charts for Monitoring an Automotive Glass Fixing Process

The purpose of this paper is to present parameters of Shewhart control charts to monitor the mean and variability of an automotive industry process. The process consists of preparing and applying polyurethane glue for attaching glass of a panoramic roof to a vehicle. The amount of glue applied must follow the height and length standard specified by Engineering. These are the two quality characteristics considered critical regarding quality and safety for customer. Limits of control plot to monitor the mean and sample amplitude are estimated with 50 size 6 samples, following the principle of rational subgroups. Graphs constructed serve to monitor the quality characteristics of process, and it is possible to evaluate wheather there are special causes that alter the average and/or the variability of process.