Using a Design FMEA

How building reliability into the equipment design will dramatically improve your profitability.

Part 2 of 5

Products and equipment start with a design. The functions and performance occur or do not occur according to the capabilities designed into the system.

I learned early in my career, as a manufacturing engineer, that some products were much easier to manufacture (less yield loss) than others, and it was often the design of the product that made the difference.

I also learned that once we purchased and installed factory equipment it was very difficult to improve the reliability performance.

In both cases, I learned that working with the design team is essential in order to achieve reliability performance of either the products you are producing or the equipment in your plant.

As James Kovacevic discussed in the article, “Incorporating Reliability into Your Future”, designing and creating an inherently reliable piece of equipment takes intention. See the ebook with all five articles below. In this article, let’s explore an excellent tool to translate the desire to specific actions that help you accomplish an inherently reliable system.

No One Likes to Hear About Failures

Talking about how a product or system can fail is rarely the first topic your team wants to talk about.

You might think about failures as you plan for spares, warranty costs, or maintenance/repair processes, yet mentioning failures in most organization is not widely discussed.

It’s bad somehow to consider that a system could fail. It is supposed to just work. You may become labeled a ‘nay-sayer’ or ‘troublemaker’ by talking about potential failures.

Yet, without understanding what may fail, we have little chance to avoid those failures. We need a tool that permits us to safely discuss potential failures that lead to design improvements. This too is Failure Mode and Effects Analysis, FMEA.

Introduction to Design FMEA

FMEA is a structured team discussion concerning the potential failures. When considering a design, it considers how the design may not operate or function as expected.

An FMEA typically considers three facets of potential failures:

The consequence or severity of a failure. What happens when a failure occurs?
The frequency of the initiating causes of a failure. How many failures to expect?
The detection of the causes. Can we spot a failure cause and avoid the consequence?

An FMEA reference that I reach for regularly is concise and easy to use with your team The Basics of FMEA, 2nd Edition, by Robin E. McDermott, et.al.

Focus on What Could Go Wrong

The primary focus of an FMEA is to allow the team to focus on potential failure modes. In short, let’s get the team together to talk about what might not work as expected.

One of the primary benefits is we accomplish two things that help our team, product and system function better.

First, we may learn of areas of high risk of failure and can focus our attention there to make necessary improvements.

Second, we align the team on the critical few elements that will require resources and talent to solve.

Most designers have a short list of what could fail. And, they tend to design away from those potential failures. Henry Petroski writes about this engineering behavior in the book Design Paradigms: Case Histories of Error and Judgment in Engineering. Bringing the team together allows the team to first learn of other potential failures, second, discover other risks, and third, to together determine which of the many issues require solutions.

Products and systems will fail. The failure will occur in part due to the design not suitable for the use, stress, or operation. While not all failures are due to poor design, they are the most difficult to fix after the design is complete, thus work with your design teams to get the reliability right, right in the design.

In the next article in this series, James Kovacevic talks about the role of maintenance with respect to reliability.

We’re thinking about adding a course on maintenance reliability, let us know what you think and what you would like to see offered.

All five articles in this series in one short ebook, interested?