Springer Series in Reliability Engineering For furthervolumes: http://www.springer.com/series/6917 Krzysztof Kołowrocki • Joanna Soszyn´ska-Budny Reliability and Safety of Complex Technical Systems and Processes Modeling—Identification—Prediction— Optimization 123 Krzysztof Kołowrocki Joanna Soszyn´ska-Budny Maritime University Maritime University ul. Morska81-87 ul. Morska81-87 81-225 Gdynia 81-225 Gdynia Poland Poland e-mail: [email protected] e-mail: [email protected] ISSN 1614-7839 ISBN 978-0-85729-693-1 e-ISBN978-0-85729-694-8 DOI 10.1007/978-0-85729-694-8 SpringerLondonDordrechtHeidelbergNewYork BritishLibraryCataloguinginPublicationData AcataloguerecordforthisbookisavailablefromtheBritishLibrary (cid:2)Springer-VerlagLondonLimited2011 Apart from anyfair dealing for the purposes of researchor privatestudy, or criticismor review,as permittedundertheCopyright,DesignsandPatentsAct1988,thispublicationmayonlybereproduced, stored or transmitted, in any form or by any means, with the prior permission in writing of the publishers,orinthecaseofreprographicreproductioninaccordancewiththetermsoflicensesissued bytheCopyrightLicensingAgency.Enquiriesconcerningreproductionoutsidethosetermsshouldbe senttothepublishers. Theuseofregisterednames,trademarks,etc.,inthispublicationdoesnotimply,evenintheabsenceof aspecificstatement,thatsuchnamesareexemptfromtherelevantlawsandregulationsandtherefore freeforgeneraluse. The publisher makes no representation, express or implied, with regard to the accuracy of the informationcontainedinthisbookandcannotacceptanylegalresponsibilityorliabilityforanyerrors oromissionsthatmaybemade. Coverdesign:eStudioCalamar,Berlin/Figueres Printedonacid-freepaper SpringerispartofSpringerScience+BusinessMedia(www.springer.com) Preface This book is concerned with the identification, evaluation, prediction and opti- mization of operation, reliability, availability and safety of technical systems related to their operation processes. The main emphasis is on multi-state systems composed of ageing components and changing their structures and their compo- nent’s reliability and safety characteristics during the operation processes. In this book these systems are called the complex technical systems. The practical importanceofsuchanapproachinreliabilityandsafetyidentification,assessment and prediction, and analyzing the effectiveness of operation processes of real technical systems is evident. Mostrealtechnicalsystemsareverycomplexanditisdifficulttoanalyzetheir reliability, availability and safety. Large numbers of components and subsystems andtheiroperatingcomplexitycausetheidentification,evaluation,predictionand optimization of their reliability, availability and safety to be complicated. The complexityofthesystems’operationprocessesandtheirinfluenceonchangingin time the systems’ structures and their components’ reliability characteristics are very often metinreal practice. We meet complextechnical systems, forinstance, in piping transportation of water, gas, oil and various chemical substances. Complex technical systems are also used in electrical energy distribution, in telecommunication, in rope transportation, in maritime transport and in shipyard andporttransportsystemsusingbeltconveyersandelevators.Ropetransportation systems such as port elevators and ship-rope elevators used in shipyards during ship docking and undocking are model examples of such systems. Taking into account the importance of the safety and operating process effectivenessofsuchsystemsitseemsreasonabletoexpandthetwo-stateapproach tomulti-stateapproachintheirreliabilityandsafetyanalysis.Theassumptionthat the systems are composed of multi-state components with reliability states or safety states degrading in time gives the possibility for more precise analysis of their reliability, safety and operation processes’ effectiveness. This assumption allowsustodistinguishasystemreliabilityorsafetycriticalstatetoexceedwhich iseitherdangerousfortheenvironmentordoesnotassurethenecessarylevelofits operation process effectiveness. Then, an important system reliability or safety v vi Preface characteristic is the time to the moment of exceeding the system reliability or safety critical state and its distribution, which is called the system risk function. Thisdistributionisstrictlyrelatedtothesystemmulti-statereliabilityfunctionand thesystemmulti-statesafetyfunctionandthesearethebasiccharacteristicsofthe multi-state system. In the case of large systems, the determination of the exact reliability functions of the systems and the system risk functions leads us to very complicatedformulaethatareoftenuselessforreliabilitypractitioners.Oneofthe important techniques in this situation is the asymptotic approach to system reli- abilityevaluation.Inthisapproach,insteadofthepreliminarycomplexformulafor the system reliability function, after assuming that the number of system com- ponentstendstoinfinityandfindingthelimitreliabilityofthesystem,weobtainits simplified form. This aspect of complex technical systems is also considered in this book. Theconvenienttoolsforanalyzingtheseproblemsaresemi-Markovmodeling the systems’ operation processes and multi-state approach to the systems’ reli- ability evaluation that is proposed in this book. Theaimofthisbookistopresentthegeneralreliability,availabilityandsafety analytical models of complex non-repairable and repairable multi-state technical systemsrelatedtotheiroperationprocessesthataredevelopedbytheauthorandto apply them practically to real industrial systems and processes. The integrated generalmodelsofcomplexindustrialsystems,linkingtheirreliability,availability andsafetymodelswiththeiroperationprocessmodelsandconsideringvariablein different operation states their reliability and safety structures and their compo- nents reliability and safety parameters are proposed. The common usage of the multi-state systems’ reliability and availability models and the semi-Markov model for the systems’ operation processes in order to construct the joint general system reliability and availability models related to their operation process is the mainideaofthebook.Thejointmodelslinkingthereliabilityandsafetymodelsof the multi-state systems and their varying in time operation processes models are constructed and applied in the reliability, availability and safety analysis of real complextechnicalsystems.Thesejointreliabilityandsafetymodelstogetherwith the linear programming are proposed for the reliability, availability and safety optimization and operation cost analysis of the complex technical systems. The models and methods proposed in this book proposed in the book models and methods are applied to reliability, availability and safety analysis, identifi- cation,predictionandoptimizationoftheportandmaritimetransportationsystems related to varying in time their operation processes, structures and components reliability and safety parameters. This book delivers a complete elaboration of the state of art on the method of reliability and safety identification, evaluation, prediction and optimization for as wideaspossiblearangeofcomplextechnicalsystems.Pointingoutthepossibility ofthismethod’sextensivepracticalapplicationintheoperatingprocessesofthese systems is also an important reason for this book. This book contains complete actual solutions of the formulated problems for the considered complex technical systems in the case of the exponential multi-state reliability functions of their Preface vii components.Thisassumptionisnecessaryintheanalyticalapproachtothesubject considered. This book consists of a Preface, Chaps. 1–7 presenting the main theoretical results and their practical applications, Summary and Appendices including sta- tistical tables that are used in the book. References suitable to the subjects con- sidered in the particular chapters are provided at the end of each chapter. In the Preface, the book introduction and its contents are presented. In Chap. 1, the basic notions of ageing multi-state systems reliability analysis are introduced. The system components and the system multi-state reliability functions are defined. The mean values and variances of the multi-state systems’ lifetimesinthereliabilitystatesubsetsandthemeanvaluesoftheirlifetimesinthe particular reliability states are defined. The multi-state system risk function and themomentofexceedingbythesystemthecriticalreliabilitystateareintroduced. Themulti-stateseries,parallel,‘‘moutofn’’,consecutive‘‘moutofn:F’’,series- parallel, parallel-series, series-‘‘m out of k’’, ‘‘m out of l’’-series, series-consec- i i utive‘‘moutofk:F’’andconsecutive‘‘m outofl:F’’-seriesreliabilitystructures i i of the multi-state systems with degrading (ageing) components are defined and theirreliabilityfunctionsdetermined.Asaparticularcase,thereliabilityfunctions oftheconsideredmulti-statesystemscomposedofcomponentshavingexponential reliabilityfunctionsaredetermined.Moreover,themulti-stateapproachtoanalysis and defining the basic notions of the systems’ safety is proposed. The system safety function and the system risk function that allow to define basic safety structures of the multi-state systems composed of components with degrading safety states are introduced. Applications of the proposed multi-state system reliability and safety models to the evaluation and prediction of the reliability characteristicsofanexemplarysystemandaportoiltransportationsystemandthe safety characteristics of a maritime ferry technical system are presented as well. InChap.2,theoperationprocessofthecomplextechnicalsystemisconsidered and its operation states are introduced. The semi-Markov process is used to con- struct a general probabilistic model of the considered complex technical systems operation processes. To build this model the vector of probabilities of the system operationprocessstrayingattheinitialoperationstates,thematrixofprobabilities ofthesystemoperationprocesstransitionsbetweentheoperationstates,thematrix of conditional distribution functions and the matrix of conditional density func- tions of the system operation process conditional sojourn times at the operation states are defined. To describe the system operation process the conditional sojourn times at the particular operation states, the uniform distribution, the tri- angular distribution, the double trapezium distribution, the quasi-trapezium dis- tribution, the exponential distribution, the Weibull distribution and the chimney distribution are suggested and introduced. Based on these assumptions from the constructed model, the main characteristics of the system operation process are found.Themeanvaluesofthesystemoperationprocessconditionalsojourntimes at the particular operation states having these distributions are given. Moreover, the distribution functions of the system operation process unconditional sojourn times at the particular operation states, the mean values of the system operation viii Preface process unconditional sojourn times at the particular operation states, the limit values of the transient probabilities of the system operation process at the par- ticular operation states and the approximate mean values of the system operation process total sojourn times at the particular operation states for the fixed suffi- ciently large system operation time are determined. Applications of the proposed modelfortheevaluationandpredictionoftheoperationprocesses’characteristics oftheexemplarysystem,theportoiltransportationsystemandthemaritimeferry technical system are presented as well. In Chap. 3, there are presented the general reliability, availability and safety analytical models of complex non-repairable and repairable multi-state technical systems related to their operation processes. They are the integrated general models of complex technical systems, linking their multi-state reliability, avail- ability and safety models with their operation process models and considering variable at the different operation states their reliability and safety structures and their componentsreliabilityandsafety parameters. Theconditional reliabilityand safety functions at the system particular operation states and independent of the system particular operation states the unconditional reliabilityand safetyfunction and the risk function of the complex technical systems are defined. These joint models of the reliability, availability and safety and the variable in time system operation processes are constructed for multi-state series, parallel, ‘‘m out of n’’, consecutive ‘‘m out of n: F’’, series-parallel, parallel-series, series-‘‘m out of k’’, ‘‘m outofl’’-series,series-consecutive‘‘moutofk:F’’andconsecutive‘‘m outof i i i l: F’’-series systems. The joint models are applied for determining the reliability, i availability, renewal and safety characteristics of these systems related to their varying in time reliability and safety structures and their components’ reliability and safety characteristics. Under the assumption that the considered systems are exponential,theunconditionalreliabilityandsafetyfunctionsofthesesystemsare determined. Moreover, in the case of large-scale systems, the possibility of combining the results coming from these joint models and the results concerning the limit reliability functions of the considered systems is briefly presented. The proposed models and methods are applied for the reliability and availability analysis,evaluationandpredictionoftheexemplarytechnicalsystemandtheport oil piping transportation system and for the safety analysis, evaluation and pre- diction of the maritime ferry technical system related to varying in time their operation processes, structures and components’reliability and safetyparameters. In Chap. 4, there are presented the methods of identification of the operation processesofcomplextechnicalsystems.Thesearethemethodsandproceduresfor estimating the unknown basic parameters of the system operation process semi- Markov model and identifying the distributions of the conditional system opera- tion process sojourn times at the operation states. The formulae estimating the probabilitiesofthesystemoperationprocessstrayingattheoperationstatesatthe initial moment, the probabilities of the system operation process transitions between the operation states and the parameters of the distributions suitable and typical for the description of the system operation process conditional sojourn times at the operation states are given. Namely, the parameters of the uniform Preface ix distribution, the triangular distribution, the double trapezium distribution, the quasi-trapezium distribution, the exponential distribution, the Weibull’s distribu- tion and the chimney distribution are estimated using the statistical methods such as the method of moments and the maximum likelihood method. The chi-square goodness-of-fit test is described and proposed to be applied for verifying the hypotheses about these distributions’ choice validity. The procedure of statistical data sets’ uniformity analysis based on Kolmogorov–Smirnov test is proposed to beappliedtotheempiricalconditionalsojourntimesattheoperationstatescoming from different realizations of the same complex technical system operation pro- cess. The applications of the proposed statistical methods of the unknown parametersidentificationofthecomplextechnicalsystemoperationprocessmodel for determining the operation parameters of the exemplary system, the port oil transportation system and the maritime ferry technical system are presented. The procedure of testing the uniformity of statistical data sets is applied for the real- izations of the conditional sojourn times at the operation states of the ferry tech- nical system collected at two different operating conditions. In Chap. 5, there are presented procedures and formulae estimating the unknown parameters of the complex technical system components reliability and safety models on the basis of statistical data coming from the components reli- ability and safety states changing processes. The maximum likelihood method is appliedtoestimatingtheunknownintensitiesofdeparturesfromthereliabilityand safety state subsets of the multi-state system components having different expo- nential reliability functions at various system operation states. This method is appliedtothestatisticaldatacollectedindifferentkindsofempiricalexperiments, includingcasesofsmallnumberofrealizationsandnon-completedinvestigations. The goodness-of-fit test applied to verify the hypotheses concerned with the exponential forms of the multi-state reliability functions of the particular com- ponents of the complex technical systems at the variable operations conditions is presented.Inthecaseoflackofdatacomingfromthecomponents’reliabilityand safetystateschangingprocesses,thesimplifiedmethodofestimatingtheunknown intensities of departures from the reliability and safety state subsets based on the expertopinionsisproposed.Applicationsoftheproposedstatisticalmethodsofthe unknown parameters identification of the complex technical system components reliability and safety models to determine the reliability parameters of the exemplarysystemandtheportoiltransportationsystemcomponentsandthesafety parameters of the maritime ferry technical system components are presented as well. InChap.6,themethodsbasedontheresults ofthejointmodellinkingasemi- Markovmodelingofthesystemoperationprocesseswithamulti-stateapproachto system reliability and safety and the linear programming are proposed to the complex technical systems at the variable operation conditions operation, reli- ability, availability and safety optimization and cost analysis. The method of optimizationofthecomplextechnicalsystemsoperationprocessesdeterminingthe optimal values of limit transient probabilities at the system operation states that maximizethesystemlifetimesinthereliabilityorsafetystatesubsetsisproposed. x Preface Thewayofoperationcostanalysisofthecomplextechnicalsystematthevariable operation conditions and its application for the evaluation of the cost before and after this system operation process optimization is presented. The methods of corrective and preventive maintenance policy maximizing the availability and minimizing the renovation cost of the complex technical systems at the variable operation conditions are presented as well. The proposed methods are applied to the operation, reliability and availability optimization and operation cost analysis of the exemplary technical system and the port oil piping transportation system andtotheoperationandsafetyoptimizationofthemaritimeferrytechnicalsystem related to varying in time their operation processes, structures and components reliability and safety parameters. The procedures of the corrective and preventive maintenance policy optimization are proposed and applied to the exemplary sys- tem, the port oil piping transportation system and the ferry technical system. InthecomplementaryChap.7,themethodsbasedontheresultsincludedinthe book that are not used in previous chapters, are applied to the reliability, avail- ability and safety identification, prediction and optimization of various kinds of systems. Direct applications of the results stated in the propositions of Chap. 3 to the reliability, renewal and availability characteristics prognosis of the series and parallel systems operating at the variable operation conditions are presented. The results of the asymptotic approach to the reliability analysis of large systems are applied tothereliabilitypredictionofthe large parallel-series system operating at the varying conditions. The safety analysis of the steel cover is performed using the results concerned with the consecutive ‘‘m out of n: F’’ systems. Finally, the comprehensiveapplicationofthemethodsoftheoperation,reliability,renewaland availability modeling, identification, prediction and optimization to the container gantrycraneisperformedtopracticallyillustratetheoverallapproachtoreliability and safety analysis of any complex technical systems. This book concludes with a Summary that contains the evaluation of the presented results, the formulation of open problems concerned with complex technicalsystemsreliabilityandsafetyandtheperspectiveoffurtherinvestigations on the considered problems. Contents 1 Modeling Reliability and Safety of Multistate Systems with Ageing Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Reliability Analysis of Multistate Systems . . . . . . . . . . . . . . . . 1 1.3 Safety Analysis of Multistate Systems . . . . . . . . . . . . . . . . . . . 22 1.4 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 1.4.1 Reliability of Exemplary System. . . . . . . . . . . . . . . . . . 24 1.4.2 Reliability of Port Oil Piping Transportation System. . . . 33 1.4.3 Safety of Maritime Ferry Technical System. . . . . . . . . . 40 1.5 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 2 Modeling Complex Technical Systems Operation Processes. . . . . . 53 2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 2.2 Semi-Markov Model of System Operation Process . . . . . . . . . . 53 2.3 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62 2.3.1 Operation Process of Exemplary System . . . . . . . . . . . . 62 2.3.2 Operation Process of Port Oil Piping Transportation System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 2.3.3 Operation Process of Maritime Ferry Technical System . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 2.4 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 3 Complex Technical Systems, Reliability, Availability and Safety Evaluation and Prediction. . . . . . . . . . . . . . . . . . . . . . 79 3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 3.2 Reliability of Multistate Systems at Variable Operation Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 3.3 Asymptotic Approach to Reliability of Large Multistate Systems at Variable Operation Conditions . . . . . . . . . . . . . . . . 89 xi