viewing the average and range over the time span (Fig 8). It has been
described that after receiving 20 samples and inscription of this
to a suitable form, then counting of limits control for average
value and range value, then the process is stable [8]. The
quality index capability value Cp is calculated from the
obtained value. The result from this research revealed that the
SPC techniques are used for the prediction of what will occur in
the future. Control chart along with process capability
determines the quality level and gives an alarm signal.