7 . Process control & metrics (monitoring)

Relying solely on final end-of-line yield metrics is a lagging indicator; by the time the reported yield drops, the scrap has accumulated and the financial impact is already realized. To thrive in high-reliability manufacturing, we must monitor and react to leading indicators in real-time using Statistical Process Control (SPC).

In this chapter, we detail the daily application of formal control charts (X-bar/R, p-charts) to relentlessly monitor all defined Critical-to-Quality (CTQ) parameters. By clearly differentiating between inherent common cause variation and assignable special cause variation, Engineering and Production teams are empowered to safely intervene and correct the equipment before a drifting process shifts out of its required specification limits.