Your Reliability Engineering Professional Development Site
Find all articles across all article series listed in reverse chronological order.
Evaluation of reactive chemical hazards can range from simple paper-based calculations to highly complex testing and modeling. This post is aimed at helping you formulate a systematic strategy for evaluating reactive chemical hazards in your facility. I will divide the various approaches in three tiers – simple to complex.
How does Earn Value Management (EVM) reduce project risk? To answer this question, you have to understand what EVM is.
EVM is the tool used to measure progress against the PMB. (Performance Measurement Plan). EVM identifies poorly performing WP (Work Packages) and problem trends early in the project allowing maximum time to identify the root cause of the problem and identify an action plan to fix the problem.
PLANT WELLNESS WAY EAM METHODOLOGY USES THE ‘IONICS’ STRATEGIC ASSET MANAGEMENT PLAN FOR BUILDING AN ASSET MANAGEMENT SYSTEM
SIMPLY FOLLOW THE INDUSTRIAL AND MANUFACTURING WELLNESS BOOK TO CREATE YOUR ORGANIZATION’S ISO 55001 SAMP
In this episode, we talk about the more personal (or human) aspect of equipment Reliability. Who is responsible for Reliability? We know the answer is “everyone” – from top management to the experts who operate and maintain our machines. So it’s vital that we understand one another’s perspectives and responsibilities. We discuss how invisible obstacles can personally affect us – Comfort, the Prison of Perfection, Overwhelm, Our Thoughts, The Voices, and Fear. Fear can be the deadliest one of all. In this episode we discuss a simple – yet powerful technique – to manage fear. When we properly manage the obstacles, we free ourselves up to become more productive and effective equipment custodians.
Rupert Miller said, “Surprisingly, no efficiency comparison of the sample distribution function with the mles (maximum likelihood estimators) appears to have been reported in the literature.” (Statistical “efficiency” measures how close an estimator’s sample variance is to its Cramer-Rao lower bound.) In “What Price Kaplan-Meier?” Miller compares the nonparametric Kaplan-Meier reliability estimator with mles for exponential, Weibull, and gamma distributions.
This report compares the bias, efficiency, and robustness of the Kaplan-Meier reliability estimator from grouped failure counts (grouped life data) with the nonparametric maximum likelihood reliability estimator from ships (periodic sales, installed base, cohorts, etc.) and returns (periodic complaints, failures, repairs, replacement, spares sales, etc.) counts, estimator vs. estimator and population vs. sample.
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OSHA inspected 42 refineries between June 2007 – February 2009. Below is a summary of violations for 30 refineries. A bit of history.
There are numerous papers and documents on the internet regarding a Work Breakdown Structure (WBS). The question is how do you create one for a new project. This paper explains how.
Many people believe Proactive Maintenance is the ultimate physical asset management strategy—but there is one better strategy. To get world class reliability at the least cost there must be no maintenance. Only a “wellness” paradigm can achieve that result.
In a season 2 episode of AMC’s acclaimed TV show “Better Call Saul”, its lead character Jimmy McGill asks his assistant Omar to “take a letter” as he dictates a handful of disjointed phrases to tender his resignation from his lucrative position at the Davis & Main law firm1. During a pause between Jimmy’s thoughts, Omar blankly states, “I just didn’t realize how unhappy you were here.” Jimmy’s response, while puzzling and a bit comical, describes a concept key to understanding the nature of job satisfaction. He replies to Omar, “Not unhappy, per se. More like not happy.”
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An existing equipment in a refinery may display flaws/damages that either existed during manufacturing or were induced during service. Let us briefly look at pre-service flaws and service-induced deterioration.
Dick Mensing said, “Larry, you can’t give an estimate without some measure of its uncertainty!” For seismic risk analysis of nuclear power plants, we had plenty of multivariate earthquake stress data but paltry strength-at-failure data on safety-system components. So we surveyed “experts” for their opinions on strengths-at-failures distribution parameters and for the correlations between pairs of components’ strengths at failures.
If you make estimates from population field reliability data, do the estimates have uncertainty? If all the data were population lifetimes or ages-at-failures, estimates would have no sample uncertainty, perhaps measurement error. Estimates from population field reliability data have uncertainty because typically some population members haven’t failed. If field reliability data are from renewal or replacement processes, some replacements haven’t failed and earlier renewal or replacement counts may be unknown. Regardless, estimates from population data are better than estimates from a sample, even if the population data is ships and returns counts!
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Often used to pump slurries, helical rotor pumps (also known as progressivity cavity pump, eccentric screw pump, mono pump) use a spiral rotor to move a chamber full of product through the pump. When moving slurries it is critical that the rotor wipes the rubber or elastomer stator firmly, else fine particles get between the rotor and stator and rip material out. This article discusses a major operating problem when the wrong size rotor was used in a stator.
I have some experience with the Enneagram personality method. I found it to be accurate and useful. I suggest it is a good method to consider using to select your project team. The paper starts with a brief description of the Enneagram basics and then explains tips that can be used to select your team. Two figures are included to help explain the basics. You can go online and get a lot more detail information about the Enneagram method.
In this episode, we explore what Condition Based Maintenance (CBM) is (aka On-Condition Maintenance). We’ll talk about : – What CBM is – The biggest trap you can fall into when implementing CBM – And what governs how often you do a Condition Based Maintenance task. As asset managers, we know that most Failure Modes occur randomly, and that can seem a little intimidating or maybe even a little scary, but it doesn’t have to be because that’s where Condition Based Maintenance can be very helpful. The whole point of Condition Based Maintenance is to detect a Potential Failure Condition and take action before failure occurs. That interval is called the P-F Interval and that is explained in this episode.
During process development or plant operation it is often necessary to estimate energy of reaction based on chemical formulae representation alone. This heat of decomposition represents the potential energy that can be released and is therefore a measure of explosion potential. One can therefore envision that estimation of heats reaction based on chemical similarities should be possible similar to Benson’s group additivity for estimating heats of formation.
