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What is the essence of properly defined FMEA Functions? More than half of FMEA practitioners miss a key element when defining FMEA functions. This first article in the FMEA Definitions and Concepts Series will discuss functions and their application in FMEAs.
“A perfection of means, and confusion of aims, seems to be our main problem.”
Albert Einstein
The Maintenance Supervisor is known as the coach of the maintenance department. But what if they are pre-occupied with other tasks and unable to coach the technicians? It has the potential to increase overtime, increase rework and increase Mean Time to Repair. That is why this series continues with the Maintenance Supervisor. With the Supervisor clear on their roles and responsibilities, the technicians get the coaching they need to succeed. [Read more…]
In a previous article I alluded to Design for Test (DFT) by mentioning a specific example.
The techniques have been around for decades. Just how long ago though?
I searched on “Design for Test” in the IEEE paper data base; the search resulted in 760 references the oldest being 1983.
Hmm there had to be earlier papers? So next I plugged in the key words “Design For Testability.” This time a list of 4,235 references appeared, the oldest one published in 1978. [Read more…]
Weibull analysis is a tool that is used for characterizing the behavior of a data set. The value of characterizing a data set is being able to make predictions of failure rate for the same or a similar population. Input to the Weibull analysis is time to fail for all failed units and running time for operating units. The assumptions for the data set are critical to ensuring the right information is included in the analysis. This may include root cause analysis of the failures so they can be characterized as wear-out or use stress related. It would be beneficial to separate these two data sets because their characterization and behavior will be quite different Weibull factors. [Read more…]
ERM is a relatively new concept. There is a robust discussion among experts what it really means. Common ERM elements in most definitions include: [Read more…]
Equipment reliability studies show that the likelihood of failure increases the more often machinery is disturbed. The chance of something being done wrong rises every time an item of plant is worked on. Nothing may go wrong the first time or the second time but with each additional disruption there is an increasing possibility that an error will be made.
Simple, fast and uncomplicated access to individual items of plant and equipment means higher plant availability and longer time between failures. [Read more…]
Once reliability risks have been identified and analyzed, we have to do something.
Well, not really.
If the risk is acceptable to the stakeholders, then we can simply continue with the current plan and monitor or any new risks or changes in our understanding of the existing risks.
Risk mitigation is a ‘system, process, or investment to control the likelihood or consequence of a risk.’ This is according to the glossary of risk terms in ISO 31000: Enterprise Risk Management. In many cases, the risk is unacceptable and will require mitigation. [Read more…]
In honor of the fast approaching holiday season, let’s start the week off with a laugh or two, I have listed some of the sure-fire signs that your company may not be ready for this reliability stuff. I have to say that in my first 5 years working as a consultant, I wasn’t prepared for some of the things folks would tell me while working on site, and there were times I actually laughed when I should have just bitten my tongue. I once asked a manager if their equipment was reliable; he pondered the question a minute and replied, “It is some of the time.”
Tell me: how do you not laugh when someone says that with a straight face? [Read more…]
In these series of questions, a reader asks about whether system FMEAs in the medical device industry should include human interactions, and the difference between system and application FMEAs.
“The art of proposing a question must be held of higher value than solving it.” Georg Cantor
The Maintenance Planner / Scheduler is known as the coordinator of the maintenance department. But what if they are unsure of the priorities of the department or business? It has the potential to increase overtime, planned downtime and increase costs. That is why this series continues with the Maintenance Planner / Scheduler. With the Planner / Scheduler clear on their roles and responsibilities, the technicians can deliver the right amount of care. [Read more…]
If you had to section the history of reliability into only two periods I believe the dividing point would be around 1950. The first section, stone age to 1950, the “Robust” era; 1950 to today, the “Margin” era. In the robust, era reliability concerns were addressed by creating a design that was orders of magnitude stronger than required, “over-engineered”. This protected against the variability of fabrication, use, and environment. If it was made sloppily with low tolerances, it still worked; Used for an unintended purpose, still worked; Left out in the snow, dropped in the river, run over by a horse, buried in the sand; still worked. [Read more…]
A fluid is either a liquid or a gas. In industry, they are piped from storage to the point of use. Correct design and installation of the piping system minimises pressure loss and improves the behaviour of equipment and processes.
This article briefly explains what happens to fluids flowing through pipes. [Read more…]
We have conducted hundreds of risk assessments in a number of sectors from homeland security to pension funds to Parks and Recreation departments. We have a number of hard lessons learned. These are some common mistakes we have made and seen: [Read more…]
What happens when you power up an electronics device with clocked circuits?
Well you have a clock running and you have clocked circuit elements, also known as sequential circuits. Latches, registers, basically any “memory” element. What could interfere with testing?
Do you know the state of that “memory element” when you start?
Heck No!
That’s a problem. [Read more…]
Customers want the benefits created by your product. They want the time savings, the reduced yield loss, they want simplicity, coolness, speed, etc.
Customers buy your product to solve a problem, they do not buy it to simply enjoy the features. The features have to do something of value. They have to provide a benefit.
If your product fails, the feature doesn’t work. Customers do not realize the benefit they expected.
In short, your customer wants your product to work as expected. When asked a customer will tell you they do not want to have product failures. [Read more…]
