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Find all articles across all article series listed in reverse chronological order.
When processes trend naturally due to tool wear, traditional control charting methods fail. The trend (which is expected) results in inappropriate “out-of-control” signals. Control charts should detect unexpected changes in the process. If the trend is expected, we do not want to be alerted to this trend. If no accommodation is made for this trend, the chart will incorrectly produce “out-of-control” signals. [Read more…]
Refer to Article 7 for the expansion joint project. This project had progressed – perhaps beyond lab testing – before it was realized that the design could not meet ASME LRFD criteria. LRFD was considered necessary for reliability. The engineering manager had to consider a redesign.
Missing the LRFD may be the result of not conducting a design failure modes and effects analysis (dFMEA). FMEA is a risk discovery process. Discovering design risks early in the project improves reliability and increases profitability by avoiding redesign and schedule delays. [Read more…]
Author’s Note: I want to reiterate that this Series about reading the basic fracture surfaces, is for novices who often come into contact with such failed components. This Series is about the basics (101), and is intended to give readers an appreciation for the value of such ‘broken’ parts to an effective investigation/RCA. While this information will be rudimentary to seasoned materials engineers, I know they will all appreciate heightening awareness to the need to retain such failed parts for analysis, versus throwing them away and just replacing the part. Throwing away failed parts is a recipe for a repeat failure, when one does not understand why the part failed in the first place.
More than once or twice, I have heard, if we just got the maintenance department sorted out, our OEE would increase. I have heard this coming from not only operations and management, but also maintenance staff. While it is true that how effective and efficient the maintenance department is will have a direct impact on the operation’s performance, it is not maintenance alone that will enable success.
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“If a man does not keep pace with his companions, perhaps it is because he hears a different drummer. Let him step to the music he hears, however measured or far away.” Henry David Thoreau
One of the most important skills in facilitating team meetings is to be able to encourage balanced participation by all team members.
A while back, I felt that pretty much everything was out of sync and I was highly disorganized. There was a growing list of undone things whether that was around the house, at work, with my family, or at the places where I volunteer.
It was definitely time for a reorganization.
A few weeks later, things were back in order (I even had time to write again), and a big part of my reorganization was refocussing on the systems I use for productivity.
Emerging stronger from crisis – that’s our current challenge. We know we can do it. What doesn’t kill us makes us stronger. Our businesses can emerge stronger too, but that won’t happen without leadership and choice.
Capital asset-intensive industries that have had a chance to pause have been wise if they used the opportunity to catch up on deferred maintenance and review their proactive maintenance programs for effectiveness. They will emerge stronger. Better maintained equipment will run better, longer, and last longer, producing more and doing so with lower levels of risk.
A computer company tiger team held a meeting to decide how to fix their laser printer ghosting problem. Bearings seized in the squirrel-cage cooling fan for the fuser bar. The fan bearing was above fuser bar, which baked the bearing. A fix decision was made, voted on, and accepted. Party time. I asked, “How do you verify the fix?” Boo!
This an example of using current status life data. I checked status every laser printer laser-printer fan in company headquarters: operating or failed? Date of manufacture was encoded in the printer serial number, so I estimated the fan’s age-specific failure rate function, before the fix. Premature wearout was evident. Could I observe repaired or new printers at a later time and test the hypothesis that the problem had been fixed? Yes.
In the last article, we learned how to determine which effects are statistically significant. This is an important step to develop the predictive model(s) because only the statistically significant factors and interactions belong in the model. If we include insignificant terms in the model, the predictive ability of the model will appear to be better than it really is and we will overstate the ability of our model to predict the response(s). [Read more…]
This article is directed at those ‘first responders’ who arrive immediately at the failure scene. These are the people who have to ensure the area is safe, preserve the scene for investigators and contribute to a plan to expedite a quick, safe return to production norms.
Many do not understand how valuable failed parts are to the metallurgical/forensic investigators. Broken parts are to metallurgists’, like the murder weapon is to a forensic crime investigator.
Lubrication is often overlooked in organizations. Why it is overlooked, I am unsure. Maybe it is because it is considered to be a basic job, given to the apprentice, or it is just too simple to not to do it correctly.
However, with a focus on lubrication, many failure mechanisms can be reduced and the equipment life prolonged. But implementing an effective and world-class lubrication program is not simple. It requires a dedicated focus to implement and sustain. Below is my list of what I look for when evaluating a lubrication program.
[Read more…]
On 10 August 2020 the US Midwest experienced a Derecho that brought widespread devastation to many areas. A Derecho is a widespread, long-lived, straight-line wind storm that is associated with a fast-moving group of severe thunderstorms known as a mesoscale convective system. Derechos can cause hurricane-force winds, tornadoes, heavy rains, and flash floods. As depicted below the 10 August 2020 Derecho spanned serval states over a 12 hour period.
There’s an old saying that, “two heads are better than one”. Teamwork has been proven time and again to produce superior results. It is the basis for many successful methods like RCM-R, PMR/O, RCFA, Total Productive Maintenance (TPM) and various quality improvement programs like Six Sigma. The various methods that help us while Choosing Excellence depend on a foundation of teamwork. Beyond facilitated teamwork, self-organized teams are even more effective.
In previous articles, we discussed the advantages that Xbar charts have over Individuals charts in detecting process shifts. (See “How Should the Subgroup Size be Selected for an Xbar Chart (Part I)”) We saw that charts of Individuals are ineffective at quickly detecting small process shifts (and detecting these small process changes may be critical!).
Charts of averages (Xbar) are superior because averaging the subgroup data gives us greater certainty as to where the process is actually running at a point in time. Selecting an appropriate sample size on an Xbar chart allows us to align the statistical performance of the control chart with the desired practical process changes we’d like to detect. That is, the sensitivity (ability to detect change) may be adjusted based on the sample size utilized. [Read more…]
A high-pressure packer for use in 9 5/8”, thick-walled, P-110 casing is being developed for a well barrier application. It is based on a legacy configuration. Is it a candidate for simulation?