THE USE OF THE CONTROL CHARTS TO CONTROL THE DIMENSION OF THE CLAY BRICK UNITS

M, Dr.Tumadhir; Borhan,; Sada A. Hasan, Lecturer

	THE USE OF THE CONTROL CHARTS TO CONTROL THE DIMENSION OF THE CLAY BRICK UNITS
Al-Qadisiyah Journal for Engineering Sciences
Article 1, Volume 7, Issue 2, 2014, Pages 165-175 PDF (0 K)
Authors
Dr.Tumadhir M; ; lecturer Sada A. Hasan
Abstract
ABSTRACT Some manufactured material properties are expected to have unavoidable shifting in its average value for many reasons, however, they are still able to meet the established specifications. This case occurs when the standard deviation of the process at the various average values is very small compared to the difference between the upper and lower specification limits. On the other hand, any results out of these limits indicates that the efficiency of the process changes and the reasons have to be investigated and corrected .In this study, Al-Qadissiyah brick factory was adopted to examine the acceptance of the produced brick, in terms of its dimensions, according to Iraqi specifications. Control charts were plotted for this purpose. Two types of charts were used, the mean and the standard deviation charts. The upper and the lower limits (UCL andLCL) of each brick dimension were plotted and discussed. The results showed that the lower, the upper limits and the mean value for all dimensions are within the IQ specifications limits and the process is under control. However, the results of the length show that there is one point outside the LCL at the mean chart and one point outside the UCL at the standard deviation chart. This due to the chance causes, as it is only one point from thirteen patches .These charts can be adopted by the factory to show the production process and can be used in the future to investigate the mean of any measured patch
Keywords
quality control; Control Charts; mean chart; standard deviation chart; brick dimensions

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