A potential use for the Nonelectronic Parts Reliability Data - NPRD 2011 document is to complement existing reliability prediction methodologies by providing failure rate data in a consistent format for various electrical, electromechanical, and mechanical parts and assemblies. All part types and assemblies for which RIAC (Reliability Information Analysis Center) has data are included in this publication with the exception of selected electronic components. Although the data contained in this publication was collected from a wide variety of sources, RIAC has done everything possible to screen the raw data so that only high quality data is added to the database and presented in this document. In addition, only field failure rate data has been included.
This document is designed to provide historical reliability data on a wide variety of part types to aid engineers in estimating reliability of systems. Sound reliability engineering practices must include knowledge of failure physics for all components, modules and interconnection assemblies in a system. Knowledge of life limiting failure mechanisms and their behavior in the intended use environment is also necessary. Only in this manner robust design can be insured.
It is not feasible for documents like MIL-HDBK-217 or other prediction methodologies to contain failure rate models for every conceivable type of component and assembly. Traditionally, reliability prediction models have been primarily applicable only for generic electronic components. Therefore, NPRD-2011 serves a variety of needs:
1) To provide failure rates for assemblies (ex. disk drives) in cases where piece part level analyses are not feasible or required
2) To complement MIL-HDBK-217 and other prediction methodologies by providing data on part types not addressed by those models.
The failure rate data contained in this document represent a cumulative compilation of data collected from the early 1970's through December 2008. However, please note that some data may be periodically purged from the database whenever newer data of higher quality is obtained, or in case of obsolete part types. RIAC is continuously soliciting new field data in an effort to keep the databases current. The goals of these data collection efforts are as follows:
1) To obtain data on relatively new part types and assemblies
2) To collect as much data from many different data sources for as many application environments and quality levels as possible
3) To identify as many characteristic details as possible, including both part and application parameters.