Classify SPC out-of-control signals as a true process shift or a measurement artifact using historical pattern context, and pre-draft the investigation note for your quality engineer.
SPC systems throw control-chart alarms constantly, and one quality engineer per shift cannot triage all of them fast enough to catch real drift before scrap accumulates.
Most of that triage time goes to alarms that turn out to be measurement artifacts, not genuine process shifts.
true process shift versus measurement artifact, using historical pattern context
Confirm and investigate
An X-bar chart alarm fired on the diameter measurement for part 55-201 on Cell 3. Historical pattern context matches this cell's known gauge-drift artifact, not a genuine process shift, but the magnitude is borderline.
Try it — same review surface your operators use, with a representative decision. Nothing here is saved or sent anywhere.
Setting and revising control limits as processes and tooling wear, and the stop-the-line call, stay with your quality engineers.
See this workflow against your own queue.
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