Reliability Analysis During the Design Phase (Nonrepairable Elements up to System Failure)

Abstract

Reliability analysis during the design and development of complex components, equipment, and systems is important to detect and eliminate reliability weaknesses as early as possible and to perform comparative studies. Such an investigation includes failure rate and failure mode analysis, verification of the adherence to design guidelines, and cooperation in design reviews. This chapter presents methods and tools for failure rate and failure mode analysis of complex equipment and systems considered as nonrepairable (up to system failure, apart from Eq. (2.48)). After a short introduction, Section 2.2 deals with series - parallel structures. Complex structures, elements with more than one failure mode, and parallel models with load sharing are investigated in Section 2.3. Reliability allocation is discussed in Section 2.4, stress / strength and drift analysis in Section 2.5. Section 2.6 deals with failure mode and causes-to-effects analyses. Section 2.7 gives a checklist for reliability aspects in design reviews. Maintainability is considered in Chapter 4 and repairable systems are investigated in Chapter 6 (including complex systems for which a reliability block diagram does not exist, imperfect switching, incomplete coverage, reconfigurable systems, common cause failures, as well as an introduction to network reliability, BDD, ET, dynamic Ff, Petri nets, and computer-aided analysis). Design guidelines are in Chapter 5, qualification tests in Chapter 3, reliability tests in Chapters 7 & 8. Theoretical foundations for this chapter are in Appendix A6.