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A listing in reverse chronological order of articles by:
A reader is having difficulty seeing the difference between a detection control and a recommended action, and sees them as interchangeable. This has repercussions for the linkage between the Design FMEA and Design Verification Plan, and is the subject of this FMEA Q and A article.
“The art and science of asking questions is the source of all knowledge.”
Thomas Berger [Read more…]
Every project begins wanting to impress the customer, complete on time and perform smoothly. However, this tends to erode away quickly and the optimization objectives are saved for the next project or next phase.
But you can achieve it now!
Consider the recommended action “Review results of XYZ test to confirm requirements are achieved.” Is this a good FMEA recommended action to address a high-risk issue? Is it sufficient? Challenge your FMEA knowledge by solving this problem and other problems presented in this article.
Design of Experiments (DOE) is often only taught as a series of tools. Instead, we have used it as a tool in the Decision-Making Process which enhances implementation.
Each section below contains a 2-minute video to expand on the topic provided.
The setup and project definition are important for future success. Often, people want to jump to a solution. Then, they can start implementation and testing. Briefly pulling back to define the goal and appropriate outputs will help tremendously.
Consider these questions: How many recommendations are needed to address the root cause of a high-risk problem? If the FMEA team is addressing an issue with high-severity and high-occurrence ratings, is it usual to have a single recommended action to reduce risk? Why not? Read on, to learn the essential elements of FMEA recommended actions, and answers to this questions.
“I have been impressed with the urgency of doing. Knowing is not enough; we must apply. Being willing is not enough; we must do.”
Leonardo da Vinci
One of the more important topics in the FMEA body of knowledge is how to audit the effectiveness of FMEAs. Performing FMEAs properly and to a high quality standard is essential to obtaining the best possible results. This FMEA Q and A goes to the heart of FMEA effectiveness audits.
“Without a good question, a good answer has no place to go.”
Clayton Christensen
In this article, we use problems and solutions to learn about FMEA controls. In the intermediate problem, we continue examining the door latch-pin failure of the DC-10 cargo door, as an example to identify FMEA controls. In the advanced problem, we analyze a fictitious FMEA relating to potential safety of someone trying to unjam a snowblower.
A common error in FMEA procedure is to make entries in the Controls column that the FMEA team believes need to be done, but are not currently planned or in place. Why is this error so prevalent? Maybe the question should be why do we limit entries into the prevention or detection control column to actions or methods that are currently planned or in place?
“Never mind your mistakes. One day they will become your most prized possessions.”
Abhijit Naskar
Is it a good idea to do one generic FMEA for wiring harnesses, and use it as a reference for other FMEAs for similar applications? What about interfaces? These questions are discussed and answered in this FMEA Q and A article.
“We live in the world our questions create.”
David Cooperrider
Telematics data presents the opportunity to characterize the vehicle lifetime usage. This information is used to validate development and testing targets. Because there can be bad or missing data, it needs to be reviewed prior to analysis to have confidence in the analysis. [Read more…]
The DC-10 case study continues by asking for causes to the door latch-pin failure. The advanced problem poses a realistic and especially challenging circumstance that FMEA teams can experience.
“Judge a man by his questions, not his answers.” Voltaire
Does a cause description need to be a design or manufacturing deficiency? Why? This is one of the more important questions to consider if you want to achieve quality FMEAs.
“The effort to get at the truth has to precede all other efforts.”
Albert Einstein
In this Q and A article, a reader asks a challenging question about the linkage between FMEA boundary diagrams and Design FMEAs. There are many linkages between different elements of FMEAs, and this question/answer highlights one of the key linkages.
“In all affairs, it’s a healthy thing to hang a question mark on the thing you have long taken for granted.”
Bertrand Russell
In my prior article, “A Primer on Probability Distributions”, the usage of different types of histograms to display data was discussed. The histogram would acquire a bell shape if the data were normally distributed. The main limitation of the histogram approach is that the shape of the histogram can change radically with the selection of the bins used. Instead, a probability plot could be used.
This article discussed probability plots. They are extremely useful for the analysis of big and small data sets.
Can you identify the effect of the door latch-pin failure in this case study? The loss of the aft cargo door on the American Airlines DC-10 aircraft will be the focus of this Problems and Solutions article. This real-life case study is being used to practice identifying FMEA elements.
