The Dynamic Control Plan
William A. Levinson, P.E., FASQ, CFPIM is the principal of Levinson Productivity Systems, P.C. He is an ASQ Certified Quality Engineer, Quality Auditor, Quality Manager, Reliability Engineer, and Six Sigma Black Belt, and the author of several books on quality, productivity, and management.
Failure mode effects analysis (FMEA) and the control plan are both parts of advanced quality planning (AQP). FMEA, in fact, defines the control points or critical nodes of the control plan; process activities that must be controlled to ensure conformance of the critical to quality (CTQ) product characteristics. The dynamic control plan is a natural combination of the process FMEA and control plan into a single controlled and evolving document that promotes continual improvement of the process.
Advanced quality planning (AQP) or Advanced Product Quality Planning (APQP) consists of a synergistic set of activities for planning for quality. These include quality function deployment (QFD), design failure mode effects analysis (DFMEA), process FMEA, and a control plan. Process FMEA and the control plan are often treated separately even though the outputs of the FMEA define the control points, or critical to quality activities, of the control plan. The dynamic control plan improves on AQP by combining the process FMEA and control plan into a single living and evolving document.
- Attendees will learn the relationship between the elements of AQP including quality function deployment (QFD, a house of quality), design FMEA, process FMEA, and the control plan
- The presentation will then cover the basics of FMEA including identification of failure modes and their mechanisms, severity, occurrence, and detection ratings, and calculation of the risk priority number (RPN). A unique aspect of this presentation is, however, elaboration on the limitations of traditional FMEA. These include the fact that the RPN is the product of ordinal numbers, so it does not necessarily reflect the actual risk priority of a failure mode with respect to others, as well as the fact that risk is proportional not only to the individual chance of occurrence as reflected by the occurrence rating but also the frequency with which we are exposed to it
- The Army's Risk Management Process is a simpler alternative to FMEA when it is difficult to quantify the exact probability of occurrence and/or non-detection
- Engineering controls, error-proofing, and poka-yoke (all are similar) are superior to administrative controls that rely on worker vigilance to prevent mistakes, noting again that ongoing exposure to the risk will eventually result in mistakes regardless of the vigilance of the people who do the job. Shigeo Shingo case studies that begin with a phrase like, "The job relied on worker vigilance to prevent defects" invariably involved defects that were not prevented until error-proofing measures were taken
- The control plan includes elements such as controls, gages, sample frequencies, and measurement systems analysis to ensure quality at control points; activities that affect conformance of critical to quality characteristics
- Combination of the process FMEA with the control plan yields a dynamic control plan
Who Should Attend
Quality, manufacturing, and design engineers and technicians with AQP (or APQP in automotive) responsibilities including development of FMEAs and control plans.