Reliability Engineering consists of the systematic application of time-honored engineering principles and techniques throughout a product lifecycle and is thus an essential component of a good Product Lifecycle Management (PLM) program. The goal of reliability engineering is to evaluate the inherent reliability of a product or process and pinpoint potential areas for reliability improvement. Realistically, all failures cannot be eliminated from a design, so another goal of reliability engineering is to identify the most likely failures and then identify appropriate actions to mitigate the effects of those failures.

The reliability evaluation of a product or process can include a number of different reliability analyses. Depending on the phase of the product lifecycle, certain types of analyses are appropriate. As the reliability analyses are being performed, it is possible to anticipate the reliability effects of design changes and corrections. The different reliability analyses are all related, and examine the reliability of the product or system from different perspectives, in order to determine possible problems and assist a reliability engineer in analyzing corrections and improvements. Reliability engineering can be done by a variety of engineers including a reliability engineer, quality engineer, test engineer, systems engineer, or design engineer. In highly evolved teams, all key engineers are aware of their responsibilities in regards to reliability and work together to help improve the product using reliability engineering tools.

The reliability engineering activity should be an ongoing process starting at the conceptual phase of a product design and continuing throughout all phases of a product lifecycle. The goal always needs to be to identify potential reliability problems as early as possible in the product lifecycle. While it may never be too late to improve the reliability of a product, changes to a design are orders of magnitude less expensive in the early part of a design phase rather than once the product is manufactured and in service. Reliability engineering tools play a vital role in the development of all products.

Relex Software presents an integrated approach to reliability engineering. View our product line to learn more about how Relex Software can help you meet your goal of creating a more reliable and cost-effective product or process.

Following is an example of how the various reliability analysis techniques could be used during a Product Lifecycle Management (PLM) program. A Reliability Prediction can be performed in the conceptual design phase to "ballpark" the expected reliability of the product. If a critical failure is identified, a Reliability Block Diagram analysis can be used to see if redundancy should be considered to mitigate the effect of a single point failure. Then a Life Cycle Cost assessment can be performed to judge whether it is more cost effective to modify an existing design or to create a new one.

As the design progresses, if there are particular safety concerns, a Fault Tree analysis can be used to systematically identify the most likely causes of a safety problem. In addition, an FMEA can show the effects of a failure of key pieces of the design. The results of either of these analyses may prompt another look at a Reliability Block Diagram analysis to find a way to reduce the probability of a particular failure occurring.

As the design matures, there may be more information showing that certain failure events are dependent on other events, so a Markov analysis would be appropriate to guarantee accurate results. The ease and speed of performing routine maintenance on the product would require usage of preventative maintenance software and Maintainability techniques. And since the optimum number of spare parts will be required for service, a System Optimization and Simulation analysis can be performed.

Once prototypes are built and testing begins, you may want to start collecting failure data using Weibull analysis to help identify trends. And once the product is fielded, issues can be tracked using the FRACAS Corrective Action techniques.

Please note that although certain analysis types can begin to be used in a certain phase of a product lifecycle, they should not be limited to use during that phase. They should be "living analyses", meaning that as a design matures the analyses should be updated to reflect the changes to allow for early identification of potential issues.

Not all of the above analysis types will be appropriate for every product, process, or service. If they are appropriate, the potential advantages gained by doing an analysis need to be weighed against the costs associated with the analysis. But likewise, these same costs need to be weighed against the potential risks of not doing the analyses and not discovering potentially critical issues.

The Relex Software was designed to effectively manage these reliability activities. Because various analysis types can depend upon information from other types, the Relex software was built from the ground up as a fully integrated tool. Information learned during a particular analysis is automatically available to the other analysis types. You do not need to worry about transferring the data and getting the numbers correct as Relex does it for you. Having the breadth of analysis types, reliability techniques, and preventative maintenance software available, the Relex software is able to support you now and into the future.