ABSTRACT

Statistical Quality Control (SQC) is a method of monitoring. controlling. and improving a  process through statistical analysis. In order to measure the quality of a product. the process by ~, which such product is produced needs to be controlled. This leads to the concept of Statistical J Process Control (SPC) which in practice is a method that makes use of statistical techniques in controlling and monitoring a production process. The world in general is multivariate and so are industrial processes, and thus, this shows the need for the multivariate process control. It has been observed that the quality of star lager beer differ from bottle to bottle or from crate to crate This study covers the use of the classical multivariate charting technique using the Hotellings' T2 control chart to improve the quality of star lager beer. Eight quality characteristics were measured and at the end. principal component analysis was used to reduce the dimensionality of the quality characteristics considered to three principal quality characteristics. The Hotel lings T square control chart was then employed to improve the quality of star lager beer by eliminating out-of-control signals. A historical dataset for Nigerian breweries Aba plant was obtained and the appropriate / control limits were obtained. This provides an in control Phase I historical dataset and limits that would be used for the Phase II monitoring. the moving range chart was employed to set control limits for the individual quality characteristics considered. It was observed that carbondioxide, color and foam attest to 56.97% of the total variation in the quality of star lager beer, control limits were set for Carbondioxide, color and foam as using the moving range chart as shown in table 5.1. To improve the quality of star lager beer Nigerian breweries Aba plant should make use of the recommended control limits set and factor such as temperature of the room in which star lager beer is being produced should be taken into account.