A Series of Unfortunate MTBF Assumptions

The calculation of MTBF results in a larger number if we make a series of MTBF assumptions. We just need more time in the operating hours and fewer failures in the count of failures.

While we really want to understand the reliability performance of field units, we often make a series of small assumptions that impact the accuracy of MTBF estimates.

Here are just a few of these MTBF assumptions that I’ve seen and in some cases nearly all of them with one team. Reliability data has useful information is we gather and treat it well. [Read more…]

by Adam Bahret 1 Comment

Software Design For Reliability

With all the complaints you hear about products rebooting and software crashing, do companies really practice Software Reliability? In fact, there are some companies that do, but they are mostly in the industries that require products to have high availability, such as telecom, defense, and space, or safety-averse industries, such as medical and industrial plant operation. Most other industries don’t pay as much attention to it. The best method to increase Software Reliability without significant increases to schedules or budgets is to use a Software Design for Reliability (SDFR) approach. These are the key steps. [Read more…]

by James Kovacevic 1 Comment

What is Criticality Analysis? How Does it Work?

Understanding the risks allow effective mitigation plans to be put in place

Where is your biggest risk to the site? If you can’t answer that, than your maintenance program is most likely not adequate. As previously discussed, an effective maintenance program must align with business and its needs. A criticality analysis allows the site to understand where there are risks that must be managed. [Read more…]

by nomtbf Leave a Comment

A Life Data Analysis Challenge

Here is a Challenge: Life Data Analysis

Some years ago a few colleagues compared notes on results of a Weibull analysis. Interesting we all started with the same data and got different results.

After a recent article on the many ways to accomplish data analysis, Larry mentioned that all one needs is shipments and returns to perform field data analysis.

This got me thinking: What are our common methods and sets of results when we perform life data analysis? [Read more…]

by Fred Schenkelberg 8 Comments

Nevada Charts to Gather Data

A common and poor technique to gather field data is to count the number of returns by week or month. This can provide a graph showing the number of returns over time.

It hides information you need to understand your field failures.

Let’s take a look at a way to gather the same field failure data and retain the critical information necessary for time to failure analysis. [Read more…]

by Kirk Gray Leave a Comment

What will Advance Reliability Engineering?

In all aspects of engineering we only make improvements and innovation in technology by building on previous knowledge. Yet in the field of reliability engineering (and in particular electronics assemblies and systems), sharing the knowledge about field failures of electronics hardware and the true root causes is extremely limited. Without the ability to share data and teach what we know about the real causes of “un-reliability” in the field, it is more easily understood why the belief in the ability able to model and predict the future of electronics life and MTBF continue to dominate the field of electronics reliability

[Read more…]

by Fred Schenkelberg Leave a Comment