Your Reliability Engineering Professional Development Site
A forum post recently correctly found two of my many arguments for the eradication of MTBF incorrect or invalid. Maybe the author (HL) has a valid point. Let’s take a closer look at the note and the writer’s reasoning. [Read more…]
The mean time between failure (MTBF) is arguably the most prolific metric in the field of reliability engineering. The MTBF is used as a metric throughout a product’s life-cycle; from requirements, to validation, to operational assessment. Unfortunately, MTBF alone doesn’t tell us too much. [Read more…]
In the NoMTBF newsletter I’ve announced a contest for this site.
I’d like to invite you to write a guest post on MTBF, either good or bad, for or against, a case study or how-to-use article. Just something about MTBF.
Then, if during the week we post it the site reaches a new record for visits, I’ll send you a shiny new NoMTBF logo coffee mug. [Read more…]
MTBF is a common reliability metric. It is totally useless in most applications. So, why do we use it? And what can we do as reliability professionals to lead our industries away from using MTBF?
A recent set of forum discussions raised the idea that we use MTBF because our customers require it. Another writer suggested that MTBF is useful because it has been in use for so long, and therefore it must be useful. Another writer advertised their offer to determine MTBF for you for a small charge. [Read more…]
This is a short interactive note that let’s you play with different β values and compare the impact for a simple calculation. You may need to download and install the free Wolfram Player and plugin for your browser. You can find it at
<http://www.wolfram.com/cdf-player/
Value and MTBFThe value of any task is in the result, although a few may argue about the value in the journey itself. For reliability engineering tasks, the ability to use the output of an experiment or analysis to make decisions permits an organization to derive value from the tasks. Despite a few organizations that insist on [Read more…]
If you want to make enemies, try to change something ~Woodrow Wilson
Newton had it right, objects at rest tend to remain at rest, and objects in motion tend to stay in motion. We can say that both states resist changing into the other state unless some force acts on the object. You can feel this resistance when going around a corner in a car. You body seems to want to continue straight and it is the seat, belt buckle, door frame that conspire to bring you along with the car around the corner. [Read more…]
Anyone that knows me understands that even muttering MTBF in a conversation or even in passing will generally set me off on a anti MTBF tirade. My better friends tend to avoid the topic altogether. And those that are curious about ‘why’ will ask me. In the process I hope to help you think about MTBF and the many issues around its use, and to make or improve friendships. [Read more…]
This past week I’ve heard from a few that have taken the ASQ Certified Reliability Engineer exam. The common comment was on the use of MTBF and the exponential distribution. It seems to emphasized.
That is bad. [Read more…]
Linkedin groups are a continual source of interesting questions. We learn and share with each other to grapple with some of the common and not so common issues we face at work. For example, recently in the Plant Reliabilty & Maintenance Professionals – PRMP Linkedin group the follow in question appeared. [Read more…]
Seeing a book announcement for Duke Okes Performance Metrics: The Levers for Process Improvement made me think. The except titled “Psychological Impact of Metrics” included the notion that metrics drive behavior. That isn’t new, yet Duke went on to provide a way to determine the worthiness of metrics. [Read more…]
One of the venues for learning about reliability is the blogosphere. In some cases purely educational, others are more appropriate for the opinion page. Some comment on interesting facets of reliability and maintenance engineering, while others focus on examples of services provided.
Since posting the article about the internal policy by Grundfos I’ve had a range of discussions concerning your efforts to eradicate MTBF. Very encouraging!
The comment by Mark on the Linkedin NoMTBF group prompted me to write about this information. Mark posted: [Read more…]