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Failure Mode Effects Analysis (FMEA). Potential Failure Mode and Effects Analysis (FMEA (Forth Edition) July 2008. Aug 2008. Why Forth Edition. FMEA is a process -Focus is on knowledge, understanding and application Role of management and its sanction -For resources and monitoring
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Failure Mode Effects Analysis(FMEA) Potential Failure Mode and Effects Analysis (FMEA (Forth Edition)July 2008 Aug 2008
Why Forth Edition • FMEA is a process -Focus is on knowledge, understanding and application • Role of management and its sanction -For resources and monitoring • Clearer explanation related to forms and their use -including improved explanations for placing information in the correct columns to facilitate the analysis and product/process improvements efforts • Incorrect interpretation and reliance on RPN in the evaluation of risk priorities and improvement actions -Inappropriate use of RPN to obtain and arbitrary threshold • Improve the understanding of the role of the FMEA process throughout the APQP phases -Including continual improvement during production -FMEA is more than a static document necessary only for PPAP approval.
Improvements in the FMEA Reference Document • Changes in format • Additional examples • The need and type of management support • Linkage between DFMEA & PFMEA. • Changes to risk ranking tables • Alternative methods to reduce design risk • Consistent FMEA approach in chapter 3& 4
Ease of Reading and use • Change in format • An index is also included to aid in navigating the manual • Chapter II -Introduction, Basic Structure & Approach
Additional Examples • Additional examples and verbiage have been provided to improve the usefulness of the manual and provide a closer tie in to the FMEA process as it develops.
The Need and Type of Management Support • Reinforcement of the need for management support, interest and review of the FMEA process and the results. FMEA
The Need and Type of Management • Success of FMEA is based on: • Managements belief in FMEA. • Regular review of process and results. • Commitment of time and manpower. • Support of training. • Drive improvement through implementation of action items.
Examples of process Linkages • A “standard radius specified but hard to manufacture • Styling shapes, with look good but are hard and expensive to shape • Sharp edges which could injure the operator • Characteristics that are critical, excessive variation will cause warranty issues.
Changes to Risk Ranking Tables • Improvements to Severity, Occurrence, Detection ranking tables so that they are more meaningful to real world analysis and usage • Tables consistent with improvements to SAE J1739(Common committee membership)
Alternative Forms • The 3rd edition placed too much focus on a standard form, the 4th edition identifies alternative example forms. - The focus on the “standard form” has been replaced with several options that represent the current application of FMEA in industry. - Manual identifies the minimum information that should be contained on any form. - Allows for use of the 3rd edition form.
Alternative Methods to Reduce Design Risk • Alternative methods are introduced that • are currently being applied in industry • - FTA (Fault Tree Analysis) • - FMECA (Failure Mode Effect & Criticality Analysis) • - DRBFM (Design Review Based on Failure Mode) • See page 137 Appendix D for descriptions
Reduced Emphasis on RPN • More meaningful methods for evaluation • potential design risk. • Thresholds on RPN is clarified as a practice that is not recommended. • Priorities should not be based on RPN alone
Alternative to RPN • S and SXO ( Severity times Occurrence) • SOD ( Severity-Occurrence-Detection) • See page 135-136 Appendix C for examples
Reduced Emphasis on RPN • The 4th edition improvements will aid in • applying FMEA’s at suppliers and reduce • some of the misunderstanding and auditing • issues in relation to FMEA’s.