1. Statistical Quality Control with SPC Motivation for using SPC Page 1 October 27, 2005 Günter Faes Mail: guenter@faes.de

2. Statistical Quality Control with SPC Introduction: Dimension of Quality „Eight components of quality“ (Garvik 1987) Performanc e Will the product do the right job? 1 Reliabilit y How often does the product fail? 2 Durability How long is the „service life“ of the product? 3 Serviceabilit y How easy is it to repair the product? 4 Aesthetic s Visual appeal of the product 5 Features Additional features to the performance? 6 Perceived Quality What is the reputation of the company or its product? 7 Conformance to Standards Is the product made exactly as the designer intended? 8 The quality of a product can be evaluated in several ways...! Page 2 October 27, 2005

3. This can be reached with a team of specialists in development, manufacturing, quality engineering and other disciplines! „concurrent engineering“ Quality of design Quality of conformance Statistical Quality Control with SPC Introduction: Quality Definition Quality means fitness for use If variability in the important characteristics of a product, the quality of the product increases! Quality is inversely proportional to variability Quality improvement is the reduction of variability on processes and products! Page 3 October 27, 2005

4. Statistical Quality Control with SPC One way to reduce the variability is to use statistical process control (SPC)! Page 4 October 27, 2005

5. Regression and / or time series analysis Statistical Quality Control with SPC The way to statistical process control, SPC Factor analysis (as an example) Experiment design Model the relationship between the influential input variables and the output quality characteristics SPC EPC / feedback control (EPC = Engineering process control) FMEA, cost analysis,... Process compensation and regulation Page 5 October 27, 2005

6. Statistical Quality Control with SPC Possible SPC integration in a manufacturing process as a overview Material management Outgoing inspection Manufacturing process SP C Incoming goods Incoming inspection Customer s Incoming inspection Customer needs Product design Customer influence QM Methode (see also „Dimension of Quality“) man machin e materia l environmen t metho d Above fields take influence through variability onto the process! Process compensation and regulation QM-System Page 6 October 27, 2005

7. Statistical Quality Control with SPC Effective quality improvement be instrumental in increasing productivity and reducing cost! Page 7 October 27, 2005

8. Statistical Quality Control with SPC Page 8 October 27, 2005 Prevention Costs ● Quality planning ● Process design ● Process control ● Training ●... Appraisal Costs ● Inspection of Incoming material ● Product inspection ●... Internal Failure Costs ● Scrap ● Rework ● Retest ● Downtime ●... External Failure Costs ● Complaints ● Returns ● Warranty charges ●... Quality Costs Effectively used QM reduces the production costs!

9. Statistical Quality Control with SPC Page 9 October 27, 2005 Bibliography Introduction to Statistical Quality Control, Douglas C. Montgomery, 5e Wiley Prozessfähigkeitsmessung für die industrielle Praxis, Horst Rinne und Hans-Joachim Mittag, Hanser As outline: Control chart: http://www.faes.de/Basis/Basis-Statistik/Basis-Statistik-Regelkarten/basis-statistik-regelkarten.html SPC: http://www.faes.de/Basis/Basis-Lexikon/Basis-Lexikon-Prozessfaehigkei/basis-lexikon-prozessfaehigkei.html

10. Statistical Quality Control with SPC Page 10 October 27, 2005 Thanks for your friendly attention!