A Reliability Prediction is a way to analyze an electro-mechanical system to determine its failure rate and expected MTBF (Mean Time Between Failures). Failure Rate and MTBF are common indicators of product reliability and quality. Reliability predictions take into account all the components in your system along with design and environmental parameters known to effect reliability such as operating stresses, temperature, environment, and procurement quality level. A reliability prediction analysis uses underlying mathematical equations developed based on historical and known failure metrics to compute a predicted failure rate of your product. One of the main advantages of reliability predictions is that they can be performed during the product design stage, enabling you to preview likely reliability metrics so your can adjust your design to achieve the reliability and quality objectives you desire.
MTBF, Failure Rate, and Reliability Metrics
Failure Rate (commonly designated as λ) is the number of failures expected over a given time period and is typically expressed in terms of failures/million hours (FPMH) or failures/billion hours (FITs). Mean Time Between Failure, or MTBF, is the inverse of failure rate (1/λ) and is expressed in terms of hours. In very general terms, a system’s MTBF is the number of hours the given unit will operate on average before a failure occurs. Analysts may also refer to Mean Time To Failure, or MTTF, as a reliability measure. These reliability metrics are commonly computed using reliability prediction standards, which use statistically-based mathematical equations to assess reliability of electro-mechanical devices. The most commonly used and widely accepted standard for reliability prediction analysis are MIL-HDBK-217, Telcordia, 217Plus, NSWC Mechanical, ANSI/VITA 51.1, and China’s 299C.
Why do Reliability Predictions?
There are many advantages to performing reliability prediction analysis. The central goal is to improve product reliability and quality. It is difficult to achieve this goal without measurable statistics. It can be especially difficult in the design stage of the product lifecycle to assess reliability metrics when actual production has not yet started. Reliability predictions are helpful in this situation by allowing you to complete an MTBF evaluation of your product prior to manufacture – while design changes that improve reliability and quality can easily be implemented. Reliability predictions also provide a way to perform What-If? exercises to assess the effect of various design changes on product reliability.
Reliability Predictions: Living Analyses
Reliability predictions can be used starting from early phase design concept through to manufacturing and production. In fact, reliability predictions are most useful when used throughout your entire product lifecycle and even into next-gen product development. You can start your prediction with as much information as you have, get a quick, early assessment, then refine your analysis as your design matures to get a more and more accurate reliability assessment. As you then move onto future product revisions, you can start with your original analysis and adapt the lessons learned into your next design. In this manner, reliability predictions become a key element in your continual improvement process.
How do I do a Reliability Prediction?
If you want, you can obtain a copy of a reliability prediction standard and plug away using your calculator and pencil and paper! A more sophisticated and accurate approach is to use a tool expressly developed for performing Reliability Prediction analyses. This makes your analysis much faster and less error-prone, and successive iterations become a snap.
Relyence Reliability Prediction
The most web and mobile-friendly reliability prediction analysis tool available is Relyence Reliability Prediction, which supports complete and accurate analyses from any device and any location. Relyence Reliability Prediction fully implements MIL-HDBK-217, Telcordia, and China’s 299C and offers a host of features to make your reliability prediction tasks quick and efficient.
Contact us today so we can talk about your reliability prediction needs and how Relyence Reliability Prediction can help, or sign up today for our free trial to see Relyence Reliability Prediction in action.