APPLICATION OF STATISTICAL PROCESS CONTROL: USING VARIABLE CONTROL CHARTS

This study we observed the application of variable control charts on the data from a sugar factory, to test the quality of the sugar`s color property and compute factory`s capability. The samples are selected at systemic random sample covered all the season. Variables control charts are applied using Mintabe software program, x-bar chart, R chart, x-bar with R chart and x- bar with S chart. R chart, x- bar chart and xbar with S chart shows that the dispersion of the point are random within control limits, chart pattern seem to be of cyclic pattern, the process was in statistical control, x-bar with R chart shows that there is one point outside the lower control limit. np chart was applied to display where the defect that leads to the nonconforming a point , np chart clearly showed that the test failed at points 15,2 and 9 is grown on same said of center line and test failed at points 9,10,11,12. Process Capability was computed to monitor effect of variables, for this Factory the process uses up about 98% of the specification band. The study recommends the use of control charts to monitor the processes of the product lines and can be used as one of the tools to measure variation in the quality of specifications in factories