Accendo Reliability

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All articles listed in reverse chronological order.

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Understanding Job Satisfaction with Maslow’s Hierarchy of Needs

Understanding Job Satisfaction with Maslow’s Hierarchy of Needs

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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Uncertainty in Population Estimates?

Uncertainty in Population Estimates?

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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Pumping Abrasives With Progressive Cavity, Helical Rotor, Eccentric Screw Pumps

Pumping Abrasives With Progressive Cavity, Helical Rotor, Eccentric Screw Pumps

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.

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How to Select the Ideal Project Team

How to Select the Ideal Project Team

Guest Post by John Ayers (first posted on CERM ® RISK INSIGHTS – reposted here with permission)

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.

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What is Condition Based Maintenance and How Do You Assign Task Intervals?

What is Condition Based Maintenance and How Do You Assign Task Intervals?

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.

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Group Additivity Approach For Estimating Reactive Hazards

Group Additivity Approach For Estimating Reactive Hazards

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.

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The Royal Navy Develops a Maintenance Management System, 1624-1670

The Royal Navy Develops a Maintenance Management System, 1624-1670

1624 – Monson’s Tracts Describe Basic Asset Management 

In 1585 at the age of 16, William Monson ran away to sea as a privateer. Later, in the English Navy, he served during the defeat of the Spanish Armada. He was a ship captain, squadron commander, admiral, and eventually a member of parliament. Wikipedia quotes the 1911 Encyclopedia Britannica in calling him the “first naval officer in the modern sense of the word.” Monson is most famous as an early historian of the Royal Navy. 

Monson’s Tracts are a collection of essays written between 1624 and his death in 1643. The essays were not printed until 1682 and were finally published in 1704. The Tracts contain detailed accounts of the Royal Navy’s battles, tactics, voyages, and expeditions.

Monson’s Tracts also recorded the management structure of the dockyards, duties of specific positions, and some repair management practices of the late 1620s to 1630s. Monson criticized graft, waste, and bad management that reduced the navy’s capabilities. 

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Fatigue

Fatigue

Fatigue is a common degradation and failure mechanism. It involves localized, permanent damage to metals exposed to cyclic stress. The stress can be uniaxial, bending, or torsional resulting from a variety of sources including an applied force, vibration, acceleration and deceleration, and differences in thermal expansion between mating components exposed to heating and cooling cycles. Localized means the damage is confined to a small portion of a component or joint.

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Importance of Cultural Change in Transformations

Importance of Cultural Change in Transformations

Guest Post by John Ayers (first posted on CERM ® RISK INSIGHTS – reposted here with permission)

I am a curious about some of the new project team theories or methodologies that have arisen in the past 20-30 years that are undergoing a resurgent today primarily due to COVID -19 effect on the workforce. These theories are designed to improve performance and functioning of a project team by making people feel comfortable about speaking up and being creative without the fear of repercussion. Google and other Agile companies are in the process of implementing these methods.

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Doing Equipment Criticality is as Simple as ABC

Doing Equipment Criticality is as Simple as ABC

This activity-based costing (ABC) method calculates the actual cost of a failure incident and uses the total dollar value to the business as the means to rate equipment criticality. The criticality of an item of plant is determined by the cost consequences and losses of equipment failure across the whole company. Using this method puts a real dollar value on a production equipment loss incident. This financially robust and reliable method provides an accurate way to prioritise production equipment and to justify the necessary risk management and maintenance measures to protect against failure. It recognises that a production failure event has cost repercussions throughout an organisation affecting many people and departments, with all of them incurring costs. These costs are lost business profit that could have been earned and banked, but for the incident. The financial model reflects the actual production and maintenance practices in the operation and their cost implications to the whole organisation if they are inadequate. It delivers clear indication of the responsibility’s managers, supervisors, operators, and maintainers have of properly running, maintaining, and caring for plant and equipment to prevent production-losses to the business.

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The Window and the Mirror; A Framework for Building Credibility

The vast majority of professionals will never rise to the heights of leading a major corporation. But because of the public nature of executives and the companies they oversee, business leaders and their management methods often form effective case studies for those who manage smaller projects and organizations.

Over time, professionals who make a habit of reading trade journals and analyzing business reports can begin spotting both the useful and the futile patterns among these executives’ leadership styles. One such pattern, coined by the bestselling author of “Good to Great” Jim Collins, is called “The Window and the Mirror”.1

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Regulating Reactive Chemicals

Regulating Reactive Chemicals

Recently, members of  Congress sent a letter to OSHA chief, Jordan Barab, to expand PSM standard to address reactive chemicals.

Reactive chemicals have gained increasing attention since the Chemical Safety Board (CSB) released its report on reactive chemicals in 2002. Now I have been working in the area of reactive chemicals since 1999 and let me assure you that one cannot say let us regulate chemical A because it is a reactive chemical.

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Being Setup for Failure

Being Setup for Failure

Guest Post by Joseph Paris (first posted on CERM ® RISK INSIGHTS – reposted here with permission)

Employers don’t hire people – or assign them a project or task – in the hopes they will fail.  And employees don’t take on a job, project, or task in the hopes they will fail.  On the contraire, the expectations all around are that the outcome will be successful.

Certainly, sometimes the outcomes are not successful.  But these unsuccessful outcomes are generally more tolerated – even expected – in companies that are in their early stages or have a company culture that is more entrepreneurial and not so risk adverse.  And when an unsuccessful outcome in such companies occurs, it’s usually a disappointment (and you certainly don’t want to make being unsuccessful a habit), but it’s not usually a negative mark on the employee.

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