Summer Break
Taking a week off away from the article writing so in the vain of summer reruns, providing a list to the top five posts from the NoMTBF site.
In no particular order:
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Enjoy these again or for the first time.
As engineers laying out a factory or designing a new product we have to meet the reliability expectations of our customers. It would be great if the system would not fail or need repair, yet that is often not the case. Continue reading Customer Reliability Talk
We talk about reliability because it matters. The ability to estimate reliability allows us to make design and development decisions. The ability to monitor reliability allows us to adjust the design, suppliers or expectations about a product. Continue reading Why do we talk about reliability?
Designing to keep the useful life failure rates low is good design practice. This generally means a design that is robust, operates smoothly, incurs little temperature rise, and is as simple as it needs to be to function. Continue reading The Common Useful Life Assumption
MTBF has issues. It is commonly mis-understood and mis-used. I find it hard to interpret and use for any meaningful discussion of reliability.
The entire premise of the NoMTBF site is to encourage you to not use MTBF.
There are exhaustive writings on setting meaningful goals and metrics in the business literature. A couple of tenants seem common: Continue reading If not MTBF
I would ask why would you do that, yet I probably know.
You are looking for reliability information about a component or system. You want to know something about the expected failure rate or durability. Will it last long enough to meet your design and customer requirements?
Or, you have heard of MTBF and want to understand the acronym and metric. Maybe how to calculate the value from test results or field data. Continue reading Searching for MTBF
Every now and then we receive a customer request concerning reliability. If asked most customers would prefer no failures, low-cost of maintenance or ownership, and trouble-free long-term performance. And, many also realize that failures do occur. Thus a series of discussions occur to find the economically viable solution for both parties. Part of this discussion may include a poorly worded reliability requirement.
How you respond can help to improve the discussion and accelerate the finding of the right solution.
Just because the vendor provide the data convenient for an MTBF calculations should you settle?
No.
You have some questions to ask and some better information to gather. You may have a decision to make and using the best possible data helps you and your team make the right decision more often.
Reliability engineers usually work in support of an organization. We support a development team as they design a new product. We support a factory as they operate equipment to produce products. We support using our specialized knowledge to create and maintain reliable products or assets.
The teams we work with consider cost, time, function, technology, environmental impact and many other factors as they find a viable solution. Reliability is just one of the many considerations.
It is rare to have insight into any internal company history of serious electronic and electromechanical failures. Failure analysis and the causes of electronics or electromechanical systems failure can be a difficult investigation for any manufacturing company. Disclosure of the history and data is rarely if ever published due to the potential liability and litigation costs as well as loss of reputation for reliability and safety.
Continue reading Required Case History for Reliability Engineers
Let’s say you join a project as a reliability professional (or an engineer or manager of any type) and you discover that the team as a reliability goal stated as 5,000 hours MTBF.
What are you going to do with that information?
This past couple of weeks have been great.
First, I heard about a webinar by Craig Hillman of DFR Solutions titled “MTBF. Is There a Better Way?” and you can find the recorded event on the DFR Solutions site.
“The language we use matters.” Wayne Nelson
When we talk about our products or equipment, we may refer to the expected durability of the system.
Our customers and investors also want to know how long will it last.
When using the term, MTBF, many believe they are talking about the reliability of a device or system. A high MTBF numbers means it is a reliable item.
What we really want is the device to work over some duration without failure (or with few failures). It should perform a function as expected in the desired environment.