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“Good judgment comes from experience and experience comes from poor judgment.” Will Rogers
Much is learned by observing the mistakes companies have made in doing FMEAs. Based on the experience of over 2,000 FMEAs and working with many companies in a wide variety of applications, certain common mistakes show up repeatedly. In this article, I’ll share ten common FMEA mistakes and how to convert them into quality objectives.
More than one operational mode may need to be considered to ensure that all important failure modes are identified and analyzed in the FMEA. This article focuses on what you need to know about modes of operation when performing FMEAs.
“My favorite mode of transport is hot-air ballooning. It’s so graceful to be blown by the wind, to go where the wind takes you.” Richard Branson
Many companies miss out on the value of System FMEA and begin with lower level sub-assemblies or components. This article explains why it is usually best to begin with a properly done System FMEA.
“Big whirls have little whirls,
That feed on their velocity;
And little whirls have lesser whirls,
And so on to viscosity.”
Lewis Fry Richardson
“Prediction is very difficult, especially if it’s about the future.” Niels Bohr
In an FMEA, is it possible to think of everything that might happen in the future? What strategies can be used by FMEA teams to maximize the opportunity to anticipate what can go wrong, so risk can be reduced to an acceptable level?
[Author note: This article is being published mid-month, and is part of the FMEA Preparation series. It was earlier written, but inadvertently omitted from publication, as part of this series.]
One of the most important steps in FMEA preparation is gathering all of the relevant documents and information. If this step is missed or done inadequately the FMEA meetings will be burdened with extra tasks related to missing information, the time of the subject-matter experts will be wasted, and the FMEA results potentially compromised.
“True genius resides in the capacity for evaluation of uncertain, hazardous, and conflicting information.” – Winston Churchill
“Science is the process that takes us from confusion to understanding…” – B
Properly done, Process FMEAs should improve manufacturing and assembly processes and corresponding process controls. This article describes how PFMEAs can be used to improve process controls, which are embodied in the Process Control Plan (PCP).
“I didn’t fail the test, I just found 100 ways to do it wrong.” Benjamin Franklin
Properly done, Design FMEAs should improve product designs and test plans. This article describes how DFMEAs can be used to improve testing and analysis, which are embodied in the Design Verification Plan (DVP).
“It is not possible for minds degraded by a host of trivial concerns to ever rise to anything great.” Jean-Jacques Rousseau
One of the most important elements of excellent FMEAs is to stay focused on areas of concern. What does this mean and how should it be applied?
“Strategy without tactics is the slowest route to victory. Tactics without strategy is the noise before defeat.” Sun Tzu
The Oxford English dictionary defines “detection” as “discovery (of what is unknown or hidden); finding out.”
Reference the article Understanding FMEA Detection – Part 1 which discusses how Detection is defined and applied in FMEA.
“Luck is not chance, it’s toil; fortune’s expensive smile is earned.”
Emily Dickinson
The Oxford English dictionary defines “occurrence” as “the fact or frequency of something happening.”
Reference the article Understanding FMEA Occurrence Risk – Part 1 which discusses how Occurrence is defined and applied in FMEA.
“However beautiful the strategy, you should occasionally look at the results.”
Winston Churchill
The Oxford English dictionary defines “strategy” as “a plan of action or policy designed to achieve a major or overall aim.”
Reference the article Understanding FMEA Severity Risk – Part 1 which discusses how Severity is defined and applied in FMEA.
FMEAs take time and cost money. They should be done when a certain level of risk can be effectively addressed by the FMEA procedure. Preliminary Risk Assessment is a procedure that uses company-determined criteria to select which FMEAs to do.
“The key is to schedule your priorities.” ― Steven Covey
There is no more important task in an FMEA than correctly identifying the “Cause.” Finding the root cause is the heart and soul of FMEA procedure. When you have the right cause, it opens the door to solutions. When you have the wrong cause, nothing gets accomplished.
By continuing to ask “why,” the team will be able to discover the progression of cause-and-effect relationships behind a problem and the root cause that is below the surface.
Wisdom begins in wonder – Socrates
The rule is simple. For high-risk issues, the FMEA team needs to properly identify the cause(s) and associated failure mechanism(s). So, what exactly is a failure mechanism?
“Nature never breaks her own laws.” Leonardo da Vinci
By prepopulating the highest priority functions, along with other selected information, the FMEA team can focus their efforts on the most important functions, and minimize in-meeting time. This is the last step in FMEA preparation. However, there are specific limitations to FMEA prepopulation that must be understood and adhered to.
“Give me six hours to chop down a tree and I will spend the first four sharpening the axe.”
Abraham Lincoln