Reliability Engineering

Abstract

The use of general descriptive names. registered names. trademarks. etc. in this publication does not imply. even in the absence of a specific statement. that such names are exempt from the relevant protective laws and regulations and therefore free for general use.Typesetting: Camera-ready by author; Cover design: medio. Berlin SPINao737463 6213020-543 210 -Printed on acid -free paper PrefaceReliability engineering is a rapidly evolving discipline, whose purpose is to develop methods and tools to predict, evaluate, and demonstrate reliability, maintainability, and availability of components, equipment, and systems, as well as to support development and production engineers in building in reliability and maintainability. To be cost and time effective, reliability engineering has to be coordinated with quality assurance activities, in agreement with Total Quality Management (TQM) and Concurrent Engineering efforts. To build in reliability and maintainability into complex equipment or systems, failure rate and failure mode analyses have to be performed early in the development phase and be supported by design guidelines for reliability, maintainability, and software quality as well as by extensive design reviews. Before production, qualification tests on prototypes are necessary to ensure that quality and reliability targets have been met. In the production phase, processes need to be selected and monitored to assure the required quality level. For many systems, availability requirements have also to be satisfied. In these cases, stochastic processes can be used to investigate and optimize availability. including logistical support as well. Software often plays a dominant role, requiring specific quality assurance activities.This book presents the state-of-the-art of reliability engineering, both in theory and practice. It is based on over 25 years experience of the author in this field, half of which was in industry and half as Professor for reliability engineering at the ETH (Swiss Federal Institute of Technology Zurich). Following Chapter 1, in which basic concepts as well as the main tasks and organizational requirements for a cost and time effective quality and reliability assurance/management of complex equipment and systems are introduced, the book is structured in the following three parts:1. Chapters 2 to 8 deal with reliability, maintainability, and availability analyses and tests, with emphasis on practical aspects in Chapter 3 (selection and qualification of components), Chapter 5 (design guidelines for reliability, maintainability, and software quality),_ and Chapter 8 (quality and reliability assurance in the production phase). This part answers the question how to build in, predict, evaluate, and demonstrate reliability, maintainability, and availability. 2. Appendices Al to A5 deal with definitions, standards, and program plans for quality and reliability assurance of complex equipment and systems. This part addresses the needs of project and quality assurance managers and answers the question how t...

Modeling of railway system maintenance and availability by means of Colored Petri nets

“…In a real system, each subsystem should provide a fault treatment process when it is out of service [11]. Different maintenance strategies, which can be verified according to the purpose to be achieved, are taken into account during the modeling process [3]. To simplify the expression of the CPN model, only nets and color sets structures are discussed, no arc expressions and binding elements are involved, and the guard functions are described by logical expressions.…”

“…At the system level, the maintenance influences the reliability and availability of the system [3]. Achieving a high maintainability in the railway system requires a proper maintenance strategy.…”

A Comparative Reliability Study of Three Fundamental Multilevel Inverters Using Two Different Approaches

“…Failure can be divided into two categories: sudden and gradual. The sudden failure is considered as cataleptic failure and gradual failure is considered as degradation failure [33].…”

“…Expressing A avg as (MTBF-MTTR)/MTBF is usually avoided [33]. According to the authors of [51], increasing MTTF does not necessarily increase the value of Availability and Average Availability; also, Availability and Average Availability can be increased without changing MTTF.…”

Integrating the sequence dependent setup time open shop problem and preventive maintenance policies

“…So to achieve these, production systems should have high reliability which may be defined as the probability that a system would perform its intended function under operating conditions for a specified period of time. Therefore, the reliability function R(t) may be expressed as follows (Rausand & Høyland, 2004;Ushakov, 1994;Nakagawa, 2006: Birolini, 2007Meeker & Escobar, 2014):…”