Your Reliability Engineering Professional Development Site
Find all articles across all article series listed in reverse chronological order.
Mercedes used to be known for their outstanding reliability. They were the benchmark for 80 years ,no exageration. The new CLA250 model which is their base model has a reliability that is 140% less than the average rated car. What??? [Read more…]
In the article Process Capability I – Overview and Indices, the main process performance indices were defined. In the article Process Capability Analysis II – Estimating Percent Defective, ways to calculate the percent defective were introduced.
Next, a way to estimate estimate the percent defective was discussed in Process Capability III – Cp vs Percent Defective. The data showed the process had a Cp ~0.46, so even if centered, a high percentage of parts would be non-conforming! In industry, it is common to see a Cp of about 1. The paradigm is that if the process range is just contained within the tolerance range, it is satisfactory. Such processes are marginally capable. A process mean shift away from the target or an increase in variation significantly increases the number of non-conforming parts. Process Capability needs to be increased. At a minimum, Cp should be greater than 1.33, but larger is better.
There are two approaches to improving process capability. One is to center the process and the other is to reduce variation. Both need to be accomplished.
Kishor forward the link to the recording to me and suggest it may of interest to the Accendo Reliability community. I agree. He does a great job discussing the topic and a clear and practical manner.
The video abstract is:
IEEE Life Fellow and Hudson Chair in the Department of Electrical and Computer Engineering at Duke University Prof. Kishor S. Trivedi visited Alibaba’s Hangzhou campus on Dec. 8th and talked about technical systems’ reliability and availability assurance methods based on probabilistic models. [Read more…]
I want my customers to be successful, every one of them. Yet there are times I can see the writing on the wall and I know as hard as I might try to show them a clear path to what it takes to be successful they have their own plan. Some of them are so complex that people become confused just trying to make sense of them, and others get so hung up in the minutiae of even the simplest of steps like listing a 3 part failure mode they will word-smith themselves to a point where folks just give up. I find myself asking “why do people have to make what is really so simple into something that appears to be complex?” [Read more…]
What is TRIZ and could it help you? We take a brief look and provide the basics of what it covers. Innovation is going to be key in the next several years as companies grow and emerge. [Read more…]
Guest Post by Jim Kline (first posted on CERM ® RISK INSIGHTS – reposted here with permission)
A predictable surprise is a risk event that in some form is known within the organization. It is of a nature that if left unresolved, it could be costly. But fixing the problem appears to have larger short run costs, than long term benefits. The Volkswagen diesel emissions fraud is one such example. It also a case where the penalties imposed outweighed the short term costs. Moreover, had a risk assessment occurred at several points along the way, there might not have been a scandal. [Read more…]
What readers will learn from this article.
Compressed air is one of the most used service fluids in industry. This article introduces the basic design concepts of an air compressor and discusses some of the common problems and solutions found in both reciprocating (piston goes up and down) and rotary screw (twin, meshed, rotating, helix) air compressors. [Read more…]
In my previous article, we established some high-level objectives for lean product development as follows:
Hi Ash,
Several managers at my company have told me they think I should pursue getting my Professional Engineer license. While I am not opposed to getting it, I am just not sure it will be worth it.
What do you think?
Thanks,
-Anonymous, Cincinnati, OH
This is part of a short series on the common distributions.
The Triangle distribution is univariate continuous distribution. This short article focuses on 4 formulas of the triangle distribution.
The distribution becomes a standard triangle distribution when a = 0, b = 1, thus it has a mean at the $- \sqrt{{c}/{2}\;} -$ and the median is at $- 1-\sqrt{{\left( 1-c \right)}/{2}\;}-$. The distribution becomes a symmetrical triangle distribution when $- c={\left( b-a \right)}/{2}\;-$.
The triangle distribution is used to approximate distributions when the actual distribution is unknown and bounded, often useful for Monte Carlo simulations. Other applications include subjective representation when there is evidence of bounds and a mode, or as a substitution to the beta distribution since it is bounded. [Read more…]
There are a few ways to demonstrate statistical confidence in reliability of a design. Each has it reasons for selection. here are three of my favorites [Read more…]
Innovation is vital for company and economic growth. What is it? How can you achieve it? We begin to explore this with you.
While working in the field of Asset Management formerly known as Maintenance and Reliability for over 30 years I have worked with my share of Managers and Leaders. Those who have known me for years know that I started in the field as a Pipefitter Apprentice, worked as a Journeyman and Team Leader for a number of years, did a stint as a Maintenance Supervisor, went to night school to become a Reliability Engineer and then as a business owner working with customers around the world. [Read more…]
OK, let’s admit it. We don’t always make the best decisions. And of course, those around us don’t either. And yet, to deliver a product with all the best features to a customer or market, at a competitive price and in time to make the sale, and that also will have good reliability and long life, requires everyone to make the right decisions in a timely fashion all along the way. It doesn’t take many adverse decisions to introduce field issues, increase warranty claims and lessen product life.
Reliability management and engineering is all about using the best tools to guide our decision-making. Becoming a good reliability engineer, or decision-maker of any kind, is about learning those tools – including when and where to use them.
What readers will learn from this article.
A process logic controller is a computer designed for monitoring and controlling equipment. The personal computer that many people have at home is designed to accept signals from the keyboard or mouse and use instructions (software) to display the resulting effects on a screen (monitor). A PLC accepts signals (inputs) from sensors located throughout a piece of equipment or process plant. It then follows the instructions (program) within its memory and sends out commands (output) to operate equipment. [Read more…]
