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Über dieses Buch

High reliability, maintanability, and safety are expected fro complex equipment and systems. This book presents state-of-the-art methods and procedures used for cost and time effective quality and reliability assurance during the design and production of equipment and systems. It is based on more than 20 years experience gained by the author in research and industry.
The book covers theory, practice, and management aspects and addresses the needs of scientists, system-oriented engineers, engineers in development and production and project and quality assurance managers. The second edition has been completely updated revised and includes modern concepts such as Total Quality Management (TQM) and Concurrent Engineering.

Inhaltsverzeichnis

Frontmatter

1. Basic Concepts, Quality and Reliability Assurance of Complex Equipment and Systems

Abstract
Quality and reliability assurance of complex equipment and systems requires from all engineers involved in a project a set of specific activities from the definition to the operating phase, performed concurrently to achieve the best performance, quality, and reliability for given cost and time schedule targets. This includes definition of goals, planning and performing of analyses and tests, selection and qualification of components and materials, management of the configuration, quality and reliability growth during the pilot production, and qualification and control of production processes. Many of these activities are engineering tasks, others are more for coordination and control. This chapter introduces the basic concepts and discusses the main tasks and organizational requirements necessary to assure cost effectively the quality and reliability of complex equipment and systems. A refinement of these management aspects to conform also to TQM is given in the Appendices A1 to A5 (terms, standards, defining and realizing quality and reliability requirements, checklists for design reviews, and requirements for a quality data reporting system).
Alessandro Birolini

2. Reliability Analysis During the Design Phase

Abstract
Reliability analysis during the design and development phase is necessary to detect and eliminate reliability weaknesses as early as possible, and to perform comparative studies with respect to reliability. Such analysis includes failure rate and failure mode investigations as well as the verification that appropriate guidelines for reliability have been applied. This chapter introduces the methods for failure rate and for failure mode analyses of complex electronic and electromechanical equipment and systems. Design guidelines for reliability, maintainability, and software quality are given in Sections 5.1, 5.2 and 5.3, respectively. For reliability tests one may refer to Chapters 3,7, and 8.
Alessandro Birolini

3. Qualification Tests for Components and Assemblies

Abstract
Components and materials, as well as externally procured assemblies, can have a major impact on the quality and reliability of the equipment and systems in which they are used. Their selection and qualification must therefore be considered carefully. Besides cost and availability on the market, important selection criteria are the intended application (specific stresses), technology, quality, long-term behavior of relevant parameters, and reliability. A qualification includes a characterization at different thermal and electrical stresses, environmental tests, reliability tests, and failure analysis. This chapter deals first with the selection criteria for electronic components (Section 3.1) and then considers qualification tests for complex integrated circuits (Section 3.2), failure modes, mechanisms, and analysis of electronic components (Section 3.3), and qualificatoin tests for electronic assemblies (Section 3.4). Screening of components and assemblies are considered in Sections 8.2 and 8.3, respectively. Design guidelines for reliability at component and assembly levels are given in Section 5.1.
Alessandro Birolini

4. Maintainability Analysis

Abstract
At the equipment and system level, maintainability has a significant influence on reliability and availability. This is particularly true if redundancy has been implemented and redundant parts can be repaired on line, i.e. without interruption of operation. Maintainability thus represents an important parameter in the optimization of reliability, maintainability, and life-cycle cost. Achieving a high maintainability target requires appropriate activities which must be started early in the design and development phase, and be coordinated by a maintenance concept. To this belong fault detection and isolation (built-in tests), partitioning of the equipment or system into almost independent last repairable units (spare parts at equipment or system level), and logistical support (also including after-sales service). Because of the diversity of equipment and systems as well as maintainability requirements, a maintenance concept must generally be tailored to the specific project considered. After a brief discussion of the basic terms, this chapter introduces the maintenance concept as applied to complex equipment and systems, and deals then with maintainability calculation techniques and basic models for spare part provisioning. Design guidelines for maintainability (including testability) are given in Section 5.2.
Alessandro Birolini

5. Design Guidelines for Reliability, Maintainability, and Software Quality

Abstract
Reliability, maintainability, and software quality have to be built in into equipment or systems during the design and development phase. This has to be supported by analytical investigations (e.g. reliability predictions as in Chapters 2 and 6) as well as by a set of design guidelines. Such guidelines, for design and manufacturing, limit the influence of those causes (interface, transient, etc.) which can invalidate the model assumed for analytical investigations and contribute a priori to a good reliability, maintainability, and software quality of equipment and systems. This chapter presents a set of design guidelines for reliability, maintainability, and software quality, which have been discussed with engineers in industry and research centers.
Alessandro Birolini

6. Reliability and Availability of Repairable Systems

Abstract
Reliability and availability analysis of repairable systems is generally performed using stochastic processes, including Markov, semi-Markov, and semi-regenerative processes (system (S) designates the highest integration level of the item considered). Mathematical foundations of these processes are given in Appendix A7 and the main results for Markov and semi-Markov processes are summarized in Table 6.2. This chapter investigates systematically the reliability models encountered in practical applications. After a short introduction in Section 6.1, Section 6.2 deals in detail with the one-item structure. To unify the models and simplify calculations, Sections 6.3 to 6.6 assume that the system has only one repair crew and that no further failures can occur at system down. Starting from constant (time independent) values, repair and failure rates are generalized up to the case in which the process involved remains regenerative with only one or just a few regeneration states. Section 6.7 then deals with approximate expressions for large series/ parallel structures, assuming independent elements or using macro structures, and Sections 6.8 to 6.10 then consider briefly systems with complex structures as well as the influence of imperfect switching and of preventive maintenance. A powerful computer program (CARAP ETH) is introduced in Section 6.8.2.
Alessandro Birolini

7. Statistical Quality Control and Reliability Tests

Abstract
Statistical quality control and reliability tests are performed for estimating or demonstrating quality and reliability characteristics on the basis of data collected from sampling tests. Estimation leads to a point or interval estimate of an unknown characteristic, demonstration is a test of a given hypothesis on the unknown characteristic in an acceptance test. The estimation and demonstration of an unknown probability is investigated in Section 7.1 for the case of a defective probability p and in Section 7.2.1 for reliability, maintainability, or availability. Estimation and demonstration of a constant failure rate λ or of an MTBF = 1/λ and of an MTTR are discussed in Sections 7.2.2 and 7.3, respectively. Basic models for accelerated tests and for goodness-of-fit tests are considered in Sections 7.4 and 7.5. To simplify the notation, the term sample will be used instead of random sample. Theoretical foundations for this chapter are given in Appendix A8.
Alessandro Birolini

8. Quality and Reliability Assurance During the Production Phase

Abstract
Quality and reliability assurance activities have to be continued during the production phase. Key points are the monitoring and control of the production processes and of the item’s configuration, the performance of in-process and final tests, the screening of critical components and assemblies, and the systematic collection, analysis, and correction of defects and failures. The last measure is basic for a learning process, whose aim is to optimize the improvement of quality and reliability during production, taking into account cost and time schedule limitations. This chapter introduces the general aspects of quality and reliability assurance during production, discusses test and screening procedures for electronic components and assemblies, introduces the concept of a test and screening strategy, and discusses some models for reliability growth during production.
Alessandro Birolini

Backmatter

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