FMEA – More than a Form

By Michael Down

Failure cannot be eliminated, but if potential failures are identified and analyzed early on, you can take action to minimize the potential impact. The Failure Mode and Effects Analysis (FMEA) process provides the framework.

Does this sound familiar? A problem arises and a solution is needed. Resources are marshaled and hypotheses fly. Alternative actions are identified and tested until the solution is found and applied.

The problem is apparently solved—until some time later, when “the solution” triggers a bigger problem.

These events are not intentional. Most of the time, people are doing their best, trying to help the situation. Sometimes they underestimate the level of impact of the change and assume everything will be fine. Other times, they don’t take into account a change in usage or the environment. They often don’t realize the problem they’ve created.

The good news is that these unintentional events can often be avoided. Whether it’s a new idea, design, process, or a potential solution, the risk of failure always exists. Failure cannot be eliminated, but if potential failures are identified and analyzed early on, mitigating actions can be taken to minimize the impact if the failure occurs. The Failure Mode and Effects Analysis (FMEA) process provides the framework within which this can occur.

Purpose of FMEA
FMEA is an analytical methodology used throughout the product and process development cycle to ensure that potential problems have been identified, considered and addressed. Its most visible results are the documentation of the collective knowledge of cross-functional teams and the action items which mitigate the potential risk.

Through the Advanced Product Quality Planning (APQP) process, OEMs and suppliers identify areas of concern or risk in the design that would require a FMEA analysis. During this discussion, the Potential Failure Modes and Effects Analysis Reference Manual, 4th Ed. is used as a reference to identify key areas and methods needed to evaluate the product or process design.
Key Elements of a Quality FMEA

A FMEA can be prepared to examine the design of a single part, an assembly, the entire system or the processes used to produce them. The following required elements are common for all:

• Appropriate scope. The first step is to establish the depth and level of the analysis. This is accomplished by first identifying and scoping the area of the product or process design, by some form of boundary, block, or flowchart. The complexity of the scope will determine if a single FMEA or multiple (system level and component) FMEAs are required.
• Early start. No value exists in doing an FMEA after the design is completed or the manufacturing process has been developed. The greatest benefit is received by doing it as early as possible. Partial FMEAs can be done at the conception of design to identify key requirements and risks early in the design development cycle, and updated as the design progresses.
• Knowledgeable team. The FMEA is the collaborative effort of a team. Individual team members can affect the scope, direction, or quality of the analysis. The best FMEAs are obtained when teams include subject-matter experts associated with the design or process under review.
• Structured analysis. Simple techniques such as brainstorming can be used to evaluate risk associated with a single event, but evaluating multiple events and their possible interactions requires the structured approach offered by a FMEA. Use of FMEA assures that:

1. All potential failures are identified.
2. Effects (impact to the customer) are identified.
3. Risk assessment (severity, causes, design prevention and controls, occurrence) is made for each failure mode.

• Good discussion and dissection. The FMEA form should not drive the FMEA discussion. A “good” discussion gets down to the “mechanism” of failure or the physics of how a design or system works. If your FMEA meeting is just filling out the form, it’s a waste of time.
• Risk mitigation. Identifying and assessing risks is not enough. Actions such as redesign, elimination or reduction of the causes, or provision for early detection must be taken to mitigate their impact upon the customer. The key is to assign someone on the team to either resolve the issue or follow-up with the team members needed to resolve the issue(s).
• Proper documentation. Finally, the collaborative efforts of the team – the structured analysis, the “good” discussion and the risk mitigation – need to be captured so that the same issues are not duplicated in the future and improvements can be made. Enough detail must be documented so that the FMEA can be picked up in a year and fully understood. The FMEA should not be archived until all action items have been completed and all risks identified by the team have been resolved.

Conclusions

Today, no company can assume everything will be fine. Even simple issues can create problems that eventually lead to a loss of customers and sales. The FMEA process can be a powerful tool to reduce quality issues, cam[BS1]paigns, and warranty. FMEA should become a regular tool used by all engineers in both the manufacturing and the service industry.


Michael Down is with GMNA Advanced Vehicle Engineering – Validation-FMEA & DFM Group and chairman of the SPC, MSA, FMEA Manual Subcommittees. Source : http://aiag.informz.net