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A Beginner’s Guide to Design Failure Mode and Effects Analysis (DFMEA)

Nov. 29, 2023
Design Failure Mode and Effects Analysis puts a tool in the back pocket by giving engineers the ability to catch design hiccups before they become a big deal.

If you're just dipping your toes into the world of Design Failure Mode and Effects Analysis (DFMEA), don't worry – we've got your back. This step-by-step guide is here to walk you through your first DFMEA, offering practical insights without getting lost in the jargon. In recent years, the subset of Failure Mode and Effects Analysis (FMEA) has become a valuable tool in corporate settings, helping engineers spot potential risks in product design before significant investments are made. Let's unravel the mysteries of DFMEA together, highlighting common mistakes to steer clear of along the way. 

What is DFMEA? 

So, what's this DFMEA all about? Design Failure Mode and Effects Analysis is a systematic way of mapping your product’s early-warning system. It’s a process where design engineers make sure products not only do what they’re supposed to but also keep users happy. Think of it as a way to peek into the future and catch any design hiccups before they become a big deal. In simpler terms, DFMEA checks out the overall design of production systems and components, figuring out what might go wrong and how to fix it. It’s especially handy in industries like manufacturing, where preventing failures is a big deal. 

How Does DFMEA Work? 

DFMEA is your detective, looking at potential design failures from all angles. What follows is a breakdown of what it does: 

1. Failure Mode: This is how a design could mess up. For instance, think of a laptop freezing when you have too many programs open—that’s a failure mode. 

2. Failure Cause: This digs into why a failure mode happens, such as a defect in design, system, quality or part application. 

3. Failure Effect: This checks out what happens when things go wrong—like a frozen laptop leading to a frustrated user. 

4. Severity of Failure: This measures how bad a failure is for productivity, quality and safety. It looks at the worst-case scenario. 

In a nutshell, DFMEA helps figure out potential issues, their consequences and ways to stop them from happening. 

READ MORE: Discovering Defects: Design for Reliability Programs

Who Uses DFMEA? 

DFMEA is a team effort, usually with 4-6 people who really know their stuff, led by a product design engineer. It’s like a mini-Avengers team, but for making sure your product doesn’t go haywire. The team includes material, testing analysis and product quality engineers. Folks from other departments—such as production, service and logistics—might join in too. 

Industries That Love DFMEA 

While DFMEA is a superhero in any design process, it’s especially crucial in industries where new products and tech are rolling out fast. Industries such as automotive, aerospace, defense, industrial, manufacturing, healthcare and software are all big fans of DFMEA. It helps them tackle potential failure modes and reduce risks when introducing new products and technologies. 

How to Do DFMEA (A 10-Step Guide) 

Doing DFMEA might seem like a big task, but fear not: it’s a step-by-step process that makes sense. Here’s a simplified 10-step guide to get you started: 

Step #1: List Each System with its Function and Design Requirements 

Break down your product design into systems and components. Think of it like making a list of all the parts and what they’re supposed to do. 

Step #2: Identify the Failure Modes of Each System 

Figure out how each part might fail to meet its job. For example, think about a chair’s seat breaking—that's a failure mode. 

Step #3: Describe the Potential Effects of Each Failure Mode and Assign Severity Rating 

Think about what happens if a failure occurs. Does it make your product unusable or just a bit annoying? Assign a rating based on how bad the consequences are. 

READ MORE: Asset Management Becomes Flexible, Urgent

Step #4: Determine the Potential Causes of Each Failure Mode 

Look into why a failure might happen. It could be a design flaw, a problem in the system or something else. 

Step #5: Specify Prevention Controls and Assign Occurrence Rating 

What can you do to stop a failure cause from happening? Assign a rating based on how likely it is to occur, even with preventative measures in place. 

Step #6: Indicate Detection Controls and Assign Detection Rating 

How can you catch a failure cause before it becomes a big problem? Assign a rating based on how good your detection methods are. 

Step #7: Calculate the Risk Priority Number (RPN) 

Multiply your severity, occurrence and detection ratings to get an overall risk number. This helps you figure out which failures to tackle first. 

Step #8: Create High-Priority Recommendations 

For the high-risk failures, come up with recommendations on what to do. Think of ways to make the consequences less severe or improve prevention and detection. 

Step #9: Document Actions Taken 

Whatever actions you decide on, write them down. Keep track of what you’re doing to fix potential issues and when you get it done. 

Step #10: Re-Analyze RPNs to Decide Next Steps 

After you’ve made changes to improve your design, recalculate your risk numbers. If everything looks good, your design can move forward in the development process. 

Benefits of DFMEA 

Why bother with DFMEA? Well, it brings some pretty cool benefits: 

1. Effective Risk Management: Helps you spot potential problems early on, so you can manage risks before they become big issues. 

2. High Customer Satisfaction Ratings: Catching design problems early means your customers won’t face annoying glitches. Happy customers stick around longer. 

3. Lower Production Costs: Fixing issues early prevents costly product recalls and delays in launching your awesome product. 

4. Prioritize Action Items: DFMEA doesn’t just identify potential design issues; it also helps you figure out which ones to tackle first.  

READ MORE: Full Throttle: Digital Twins Boost Airworthiness in Legacy Airplanes

Common Mistakes with DFMEA—What to Avoid 

Even superheroes have their off days. Here are some common mistakes to avoid when diving into DFMEA: 

1. Don’t Integrate FMEA Types: Make sure you’re looking at all aspects. Don’t just focus on the design; consider how it fits into the bigger picture. 

2. Incorrect FMEA Ownership: Don’t put all the responsibility on one team. Get the folks who really understand the product to lead the charge. 

3. Incomplete Taskforces: Pick the right people for your team. Having folks who know their stuff about design and customer requirements is crucial. 

4. Poor Timing: Don’t wait until something goes wrong to think about DFMEA. Make it part of your design process from the start. 

Closing Thoughts 

Armed with this beginner-friendly guide, you’re now ready to tackle DFMEA with confidence. Use it as your compass in the world of proactive quality control. By avoiding common mistakes and making DFMEA an integral part of your design process, you’ll be on your way to creating high-quality products, keeping customers happy and managing risks like a pro. Happy designing! 

Lindsey Walker is the marketing manager for NEXGEN, a Sacramento-based industry leader in designing advanced computerized maintenance management systems and asset management software tools for utilities, facilities, public works, manufacturing and fleet industries. 

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