Statistical Process Control (SPC)

The use of variation analysis, with manual or computerized control charts, to detect irregular variations in a process as quickly as possible. Often, SPC charts display upper and lower limits for part characteristics or process parameters and show trends over time, indicating when the limits are exceeded (or are about to be exceeded) and corrective actions are needed. In some closed-loop systems, adjustments are made automatically when readings indicate that a control limit is being approached.