çetın, Suna; Bırgören, Burak
December 2007
Journal of the Faculty of Engineering & Architecture of Gazi Uni;Dec2007, Vol. 22 Issue 4, p809
Academic Journal
The purpose of quality control charts is to detect abnormal behavior of quality variables and to determine the causes of quality problems using these abnormalities. Hotelling's T² charts, the most popular multivariate quality control charts, are used to monitor several quality variables, simultaneously. In this study, Hotelling's T² charts were applied to a melting process in a brass casting factory. A Hotelling's T² chart was formed from multivariate data collected from the process when it was in control; then, the chart was applied to new process data. Chart signals that are out of control limits were analyzed, and associated root causes were investigated in order to improve the process. Mason-Young-Tracy decomposition method was employed in this investigation.


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