Define the term statistical process control. Outline the steps for setting up a control chart to ...

Statistical process control (SPC) is a methodology for monitoring a process to identify special causes of variation and to signal the need to take corrective action when it is appropriate. The outlined steps are required to develop and use control charts:

1 . Preparation
a . Choose the variable or attribute to be measured.
b. Determine the basis, size, and frequency of sampling.
c. Set up the control chart.
2 . Data collection
a . Record the data.
b. Calculate relevant statistics: averages, ranges, proportions, and so on.
c. Plot the statistics on the chart(s).
3 . Determination of initial control limits
a . Compute the upper and lower control limits.
b. Draw the center line (process average) and control limits on the chart.
4 . Analysis and interpretation
a . Investigate the chart for lack of control.
b. Identify and eliminate out-of-control points.
c. Recompute control limits if necessary.
5 . Use as a problem-solving tool
a . Continue data collection and plotting on the chart(s).
b. Identify out-of-control situations and take corrective action.