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With the Inside FMEA series of articles, my intention is to bring to life the subject of FMEA, and provide value to readers from all levels of experience.
Whether you are new to FMEA, or an FMEA expert, it is my sincere desire that each and every person who reads Inside FMEA articles will discover new insights about FMEA, and experience improved success in FMEA applications.
The first article, called “Welcome to Inside FMEA”, will introduce the series, and provide a glimpse of what is to come.
Readers are encouraged to contact me with any questions about FMEA, or feedback on Inside FMEA articles. Questions, feedback, and ideas for future articles can be sent to carl.carlson@effectivefmeas.com. I will personally respond to all questions and feedback.
I’m excited to bring this new series to Accendo, and hope you enjoy reading the articles, as much as I enjoy writing them. As I say to readers of my book, "best wishes for effective FMEAs."
Carl S. Carlson
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
“. . . not everything that can be counted counts” Albert Einstein
A key, but often missed, step in FMEA preparation is to identify and prioritize the functions that relate to the item being analyzed. These become candidate functions to be brought into the FMEA.
When creating a robust design, there is probably no more important consideration than identifying the correct parameters and associated values. A robust design is insensitive to anticipated variation and P-Diagram visually shows the relationship between what the system is designed to do, the anticipated noises the system will encounter and the correct parameters to achieve the desired outcome. P-Diagram can be an essential input to FMEA.
“Concern for man and his fate must always form the chief interest of all technical endeavors. Never forget this in the midst of your diagrams and equations.” Albert Einstein
Once you have identified the scope of the FMEA project, made the scope visible, it is time identify the FMEA team members. This article discusses the composition of the FMEA team, including why each member is needed, and the underlying reason for a cross-functional team.
“Alone we can do so little; together we can do so much.” Helen Keller
FMEA teams should agree to the ground rules that guide the analysis and the underlying assumptions that impact the entire FMEA. Failure to do so will add complexity and confusion to the resulting FMEA, and waste people’s time. Don’t miss this important step in FMEA preparation.
“Your assumptions are your windows on the world. Scrub them off every once in a while, or the light won’t come in.” Isaac Asimov
Before commencing with the FMEA meetings, it is essential to visibly show the nature and scope of the analysis. This article discusses different ways FMEA scope can be made visible, and why this is a necessary step.
“The soul cannot think without a picture” – Aristotle
Every journey begins with a statement of the goal or objective. Why would it be any different for FMEA? Yet, some FMEA teams do not clearly identifying the focus of the analysis. This sounds simple, and it is; but, it is very important. This article explains why.
“Begin with the end in mind” – Stephen Covey
This article culminates the first major milestone in the Inside FMEA series of articles: the “FMEA Fundamentals Series.” The next series is called: “FMEA Preparation Series.”
“Remember to celebrate milestones as you prepare for the road ahead.” Nelson Mandela
Can you take into account reliability or durability functions in an FMEA? How can this be done? A reader asks this question, and it is discussed and answered in this FMEA Q and A article.
“A prudent question is one-half of wisdom.”
Francis Bacon
In this week’s FMEA problems and solutions article, the intermediate problem challenges readers to prioritize a series of RPNs (with their corresponding S, O, and D). In the advanced problem, readers are asked to weigh in on a fictitious debate between advocates of traditional RPN, and advocates of criticality assessment, using only severity and occurrence.
If you haven’t yet read the article titled “Prioritizing risk for corrective actions in an FMEA – Know before you go!“, you can access it by clicking on the link.
Note from author:
Since this article was originally published, there are subsequent articles in the “Inside FMEA” series that further describe better approaches than RPN to risk prioritization. Here are links:
Is There a Better Way Than RPN?
Risk Prioritization in FMEA – a Summary
Is There a Better Way Than RPN?
Text of the original article:
One of the most important steps in FMEA procedure is prioritizing risk for corrective actions. As soon as Severity, Occurrence, and Detection ratings have been determined for each failure mode and associated cause, the next step in an FMEA is to prioritize the risk and identify which issues need corrective actions. This step has been misapplied more often than any other step in the FMEA process.
“The perfect is the enemy of the good.”
Voltaire
What if a production worker uses a different cleaning method for an assembly operation than was outlined in the operation work instructions, and the result is customer complaints and field issues. How could this be addressed in a Process FMEA? This question is discussed and answered in this FMEA Q and A article.
“I think that probably the most important thing about our education was that it taught us to question even those things we thought we knew.”
Thabo Mbeki
