Handbook of maintenance management and engineering (2009, springer verlag london

Handbook of Maintenance Management and Engineering Mohamed Ben-Daya • Salih O Duffuaa Abdul Raouf • Jezdimir Knezevic • Daoud Ait-Kadi Editors Handbook of Maintenance Management and Engineering 123 Mohamed Ben-Daya, Prof Salih O Duffuaa, Prof King Fahd University of Petroleum & Minerals (KFUPM) Department of Systems Engineering Dhahran 31261 Saudi Arabia bendaya@ccse.kfupm.edu.sa duffuaa@ccse.kfupm.edu.sa Jezdimir Knezevic, Prof Mirce Akademy Longbrook Street Exeter Hems Mews EX4 6AP United Kingdom mirce@mirce.net Daoud Ait-Kadi, Prof Université Laval Faculté de Sciences et de Génie Département de Génie Mécanique 1314E Pavillon Adrien-Pouliot Sainte-Foy, QC G1K 7P4 Canada daoud.aitkadi@gmc.ulaval.ca Abdul Raouf, Prof.Dr University of Management and Technology C-2 Johar Town Lahore-54600 Pakistan abdulraouf@umt.edu.pk ISBN 978-1-84882-471-3 e-ISBN 978-1-84882-472-0 DOI 10.1007/978-1-84882-472-0 Springer Dordrecht Heidelberg London New York British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library Library of Congress Control Number: 2009931371 â Springer-Verlag London Limited 2009 Watchdog Agentđ is a registered trademark of the Center for Intelligent Maintenance Systems, University of Cincinnati, PO Box 210072, Cincinnati, OH 45221, U.S.A http://www.imscenter.net D2BTM is a trademark of the American College of Cardiology, Heart House, 2400 N Street, NW, Washington, DC 20037, U.S.A http://www.acc.org/ Apart from any fair dealing for the purposes of research or private study, or criticism or review, as permitted under the Copyright, Designs and Patents Act 1988, this publication may only be reproduced, stored or transmitted, in any form or by any means, with the prior permission in writing of the publishers, or in the case of reprographic reproduction in accordance with the terms of licences issued by the Copyright Licensing Agency Enquiries concerning reproduction outside those terms should be sent to the publishers The use of 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 laws and regulations and therefore free for general use The publisher makes no representation, express or implied, with regard to the accuracy of the information contained in this book and cannot accept any legal responsibility or liability for any errors or omissions that may be made Cover design: eStudioCalamar, Figueres/Berlin Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) Preface To be able to compete successfully both at national and international levels, production systems and equipment must perform at levels not even thinkable a decade ago Requirements for increased product quality, reduced throughput time and enhanced operating effectiveness within a rapidly changing customer demand environment continue to demand a high maintenance performance In some cases, maintenance is required to increase operational effectiveness and revenues and customer satisfaction while reducing capital, operating and support costs This may be the largest challenge facing production enterprises these days For this, maintenance strategy is required to be aligned with the production logistics and also to keep updated with the current best practices Maintenance has become a multidisciplinary activity and one may come across situations in which maintenance is the responsibility of people whose training is not engineering This handbook aims to assist at different levels of understanding whether the manager is an engineer, a production manager, an experienced maintenance practitioner or a beginner Topics selected to be included in this handbook cover a wide range of issues in the area of maintenance management and engineering to cater for all those interested in maintenance whether practitioners or researchers This handbook is divided into parts and contains 26 chapters covering a wide range of topics related to maintenance management and engineering Part I deals with maintenance organization and performance measurement and contains two chapters Chapter by Haroun and Duffuaa describes the maintenance organization objectives, the responsibilities of maintenance, and the determinants of a sound maintenance organization In Chapter 2, Parida and Kumar address the issues of maintenance productivity and performance measurement Topics covered include important performance measures and maintenance performance indicators (MPI), measurement of maintenance productivity performance and various factors and issues like MPI and MPM systems, MPI standard and MPIs use in different industries Part II contains an overview and introduction to various tools used in reliability and maintenance studies and projects In Chapter 3, Ben-Daya presents basic statistical concepts including an introduction to probability and probability distributions, reliability and failure rate functions, and failure statistics In Chapter vi Preface 4, Ben-Daya provides an overview of several tools including failure mode and effect analysis, root cause analysis, the Pareto chart, and cause and effect diagram Part III contains three chapters related to maintenance control systems Chapter by Duffuaa and Haroun presents the essential elements and structure of maintenance control Topics included cover required functions for effective control, the design of a sound work order system, the necessary tools for feedback and effective maintenance control, and the steps of implementing effective maintenance control systems Cost control and budgeting is the topic of Chapter by Mirghani This chapter provides guidelines for budgeting and costing planned maintenance services Topics covered include overview of budgeting and standard costing systems, budgeting framework for planned maintenance, a methodology for developing standard costs and capturing actual costs for planned maintenance jobs, and how detailed cost variances could be generated to assess the cost efficiency of planned maintenance jobs The final chapter in this part is Chapter by Riane, Roux, Basile, and Dehombreux The authors discuss an integrated framework called OPTIMAIN that allows maintenance decision makers to design their production system, to model its functioning and to optimize the appropriate maintenance strategies Part IV focuses on maintenance planning and scheduling and contains five chapters Forecasting and capacity planning issues are addressed in Chapter by Al-Fares and Duffuaa Topics covered include forecasting techniques, forecasting maintenance workload, and maintenance capacity planning Necessary tools for these topics are presented as well and illustrated with examples Chapter by Diallo, Ait-Kadi and Chelbi deals with spare parts management This chapter addresses the problem of spare parts identification and provisioning for multicomponent systems A framework considering available technical, economical and strategic information is presented along with appropriate mathematical models Turnaround maintenance (TAM) is the object of Chapter 10 by Duffuaa and BenDaya This chapter outlines a structured process for managing TAM projects The chapter covers all the phases of TAM from its initiation several moths before the event till the termination and writing of the final report Chapter 11 by Al-Turki gives hands on knowledge on maintenance planning and scheduling for planners and schedulers at all levels Topics covered include strategic planning in maintenance, maintenance scheduling techniques, and information system support available for maintenance planning and scheduling Chapter 12 by Boukas deals with the control of production systems and presents models for production and maintenance planning The production systems are supposed to be subject to random abrupt changes in their structures that may results from breakdowns or repairs Part V addresses maintenance strategies and contain eight chapters Chapter 13 by Ait-Kadi and Chelbi presents inspection models Topics covered include models for single and multi-component systems, and conditional maintenance models Chapter 14 by Kothamasu, Huang and VerDuin offers a comprehensive review of System Health Monitoring and Prognostics Topics surveyed include health monitoring paradigms, health monitoring tools and techniques, case studies, and organizations and standards Ito and Nakagawa present applied maintenance models in Chapter 15 In this chapter, the authors consider optimal maintenance Preface vii models for four different systems: missiles, phased array radar, Full Authority Digital Electronic Control and co-generation systems based on their research In Chapter 16, Siddiqui and Ben-Daya provide an introduction to reliability centered maintenance (RCM) including RCM philosophy, RCM methodology, and RCM implementation issues Total productive maintenance (TPM) is the subject of Chapter 17 by Ahuja Topics include basic elements of TPM, TPM methodology and implementation issues Maintenance is an important concept in the context of warranties Chapter 18 by Murthy and Jack highlights the link between the two subjects and discusses the important issues involved Topics covered include link between warranty and maintenance, maintenance logistics for warranty servicing, and outsourcing of maintenance for warranty servicing Delay Time (DT) Modeling for Optimized Inspection Intervals of Production Plant is the title of Chapter 19 by Wang Topics covered include DT models for complex plant, DT model parameters estimation, and related developments and future research on DT modeling Intelligent maintenance solutions and e-maintenance applications have drawn much attention lately both in academia and industry The last chapter in Part V, Chapter 20 by Liyanage, Lee, Emmanouilidis and Ni deals with Integrated Emaintenance and Intelligent Maintenance Systems Issues discussed include integrated e-maintenance solutions and current status, technical framework for emaintenance, technology integration for advanced e-maintenance solutions, some industrial applications, and challenges of e-Maintenance application solutions Part VI deals with maintainability and system effectiveness and contains one chapter by Knezevic It covers topics related to maintainability analysis and engineering and maintainability management Part VII contains five chapters presenting important issues related to safety, environment and human error in maintenance Safety and maintenance issues are discussed in Chapter 22 by Pintelon and Muchiri This chapter establishes a link between safety and maintenance, studies the effect of various maintenance policies and concepts on plant safety, looks at how safety performance can be measured or quantified, and discusses accident prevention in light of the safety legislation put in place by governments and some safety organizations In Chapter 23, Raouf proposes an integrated approach for monitoring maintenance quality and environmental performance Chapter 24 by Liyanage, Badurdeen and Ratnayake gives an overview of emerging sustainability issues and shows how the asset maintenance process plays an important role in sustainability compliance It also elaborates on issues of quality and discusses best practices for guiding decisions The last two chapters deal with human error in maintenance Chapter 25 by Dhillon presents various important aspects of human reliability and error in maintenance Finally Chapter 26 by Nicholas deals with human error in maintenance – a design perspective Maintenance professionals, students, practitioners, those aspiring to be maintenance managers, and persons concerned with quality, production and related areas will find this handbook very useful as it is relatively comprehensive when compared with those existing in the market The Editors Acknowledgements The editors would like to acknowledge the authors for their valuable contributions This comprehensive handbook would not have been possible without their enthusiasm and cooperation throughout the stages of this project We also would like to express our gratitude to all the reviewers who improved the quality of this book through their constructive comments and suggestions The editorial assistance of Atiq Siddiqui and Ali El-Rayyah with type setting and Blair Bremberg with English editing is highly appreciated It takes a lot of patience to all the typesetting and proofreading tasks necessary for such a project Special thanks go to Dr Sami Elferik for his enthusiastic support We are indebted to Simon Rees and Anthony Doyle of Springer and Sorina Moosdorf of le-tex publishing services oHG for their full cooperation and continuous assistance We would also like to express our gratitude to our families for their patience Work on this book has sometimes been at the expense of their time Finally, we would like to acknowledge King Fahd University of Petroleum & Minerals for funding this project under the number SE/Maint.Mgt/331 Contents List of Contributors xxv Part I – Maintenance Organization Maintenance Organization Ahmed E Haroun and Salih O Duffuaa 1.1 Introduction 1.2 Maintenance Organization Objectives and Responsibility 1.3 Determinants of a Maintenance Organization 1.3.1 Maintenance Capacity Planning 1.3.2 Centralization vs Decentralization 1.3.2 In-house vs Outsourcing 1.4 Design of the Maintenance Organization 1.4.1 Current Criteria for Organizational Change 1.4.2 Criteria to Assess Organizational Effectiveness 1.5 Basic Types of Organizational Models 1.6 Material and Spare Parts Management 10 1.7 Establishment of Authority and Reporting 13 1.8 Quality of Leadership and Supervision 13 1.9 Incentives 13 1.10 Education and Training 14 1.11 Management and Labor Relations 14 1.12 Summary 15 References 15 Maintenance Productivity and Performance Measurement 17 Aditya Parida and Uday Kumar 2.1 Introduction 17 2.2 Performance Measurement and Maintenance Productivity 19 2.3 Maintenance Performance 21 2.4 Measurement of Maintenance Productivity 23 xii Contents 2.4.1 Maintenance Performance Indicator (MPI) 24 2.4.2 MPM Issues 24 2.4.3 MPM System 27 2.5 MPI Standards and MPIs as in Use in Different Industries 31 2.5.1 Nuclear Industry 32 2.5.2 Maintenance Indicators by EFNMS 33 2.5.3 SMRP Metrics 34 2.5.4 Oil and Gas Industry 35 2.5.5 Railway Industry 36 2.5.6 Process Industry 36 2.5.7 Utility Industry 37 2.5.8 Auto-industry Related MPIs for the CEO 38 2.6 Concluding Remarks 39 References 39 Part II – Methods and Tools in Maintenance Failure Statistics 45 Mohamed Ben-Daya 3.1 Introduction 45 3.2 Introduction to Probability 45 3.2.1 Sample Spaces and Events 45 3.2.2 Definition of Probability 46 3.2.3 Probability Rules 46 3.2.4 Conditional Probabilities 47 3.2.5 Random Variables 48 3.3 Probability Distributions 49 3.4 Reliability and Failure Rate Functions 51 3.4.1 Introduction 51 3.4.2 Reliability Function 52 3.4.3 Failure Rate Function 52 3.4.4 Mean Time Between Failure (MTBF) 53 3.5 Commonly Used Distributions 54 3.5.1 The Binomial Distribution 54 3.5.2 The Poisson Distribution 55 3.5.3 The Normal Distribution 56 3.5.4 The Lognormal Distribution 58 3.5.5 The Exponential Distribution 60 3.5.6 The Weibull Distribution 61 3.6 Failure Statistics 63 3.6.1 Types of Data 63 3.6.2 Parameter Estimation 64 References 73 Failure Mode and Effect Analysis 75 Mohamed Ben-Daya 4.1 Introduction 75 726 C Nicholas 26.5.3.4 Poor Organisational Conditions Poor organisational conditions can have a significant causal effect on the occurrence of human error in maintenance Organisational ethos, policies, procedures and practices, management, supervision, communication, technical support and similar factors can affect the expected and actual level of performance of the maintainer 26.5.3.5 Poor Environmental Conditions The maintenance task is carried out in a physical environment that will have an impact upon human performance Poor environmental conditions can be a cause of human error in maintenance The effect on performance is both physiological and psychological For example, maintenance might occur in work conditions that are too hot or too cold; in poor weather conditions that might include high humidity, wind, snow, and rain; or in facilities where there are high noise levels, dirt, poor lighting and ventilation 26.6 Design Strategies and Principles Having identified possible causes of human error in maintenance, it is clear that aircraft manufacturers can have a significant impact on the incidence of human error in maintenance through system design and, more specifically, the interface between human and machine Aircraft can be designed to be robust to human error and the consequences of human error not only during operation but also during maintenance Based on the analysis of error leading to the identification of the fundamental human performance influencing factors, it is evident that the aircraft designer can have an impact on the potential for human error in maintenance through the design of elements such as: • • • • • • System; Component; Orocedures and tasks; Tools and equipment; Information and documentation; and Initial training There has long been a philosophy in aircraft design that errors by maintainers are not the concern of the designer – maintainers should be trained not to make errors That philosophy is rapidly changing Designers have an important role to play because design characteristics have a significant impact on the form, frequency and duration of the maintenance task and have important implications for the possible occurrence of maintenance error As previously stated, the maintainer and the aircraft interact through the maintenance task It is through the maintenance task that the aircraft affects the Human Error in Maintenance – A Design Prospective 727 performance of the maintainer and the maintainer affects the performance of the aircraft The design of the system or component will influence the type, frequency and duration of maintenance tasks carried out in operation Key questions for the designer to consider are: • • • • What types of maintenance tasks does the design generate and what actions they involve? How often is the maintenance task needed and how long will it take? What demands does the design place upon the capabilities of the maintainer to complete maintenance task? and Can the demands of the task exceed the possible limitations of the maintainer? The complexity of design configuration, physical form, weight, location, access, method of installation, visual information and similar factors play an important part in determining the demands placed upon the level of maintenance performance required to complete a maintenance task successfully Different designs will have different effects on maintenance performance For example, the use of fewer parts may influence how easy it is to the task – improving maintenance performance and reducing the likelihood of maintenance error Aircraft maintenance often involves complex processes that place considerable demands upon the maintainer to perform at the level required by the maintenance task Maintenance often occurs in environments that also often place considerable demands upon the maintainer It is important to recognise the human capabilities and limitations of the maintainer and the capabilities and limitations that are inherent in any aircraft design It involves the design of aircraft so that the relationship between the aircraft design and the maintainer effected through the maintenance task will result in optimal maintenance performance that minimises demands on maintainers that could lead to maintenance error The design of aircraft systems and components and the operational environment in which that design functions will influence the behavior of the maintainer – for example, how easy it is to complete the task Design characteristics can generate tasks that are within the capabilities and limitations of the maintainer that have a potentially positive effect on maintenance performance Equally, design characteristics can challenge the capabilities and limitations of the maintainer and have a potentially negative effect on maintenance performance Amongst other consequences, such as decreased maintenance efficiency, this could lead to error or personal injury during maintenance Design can therefore affect the vulnerability of an aircraft to maintenance error and the consequences of that error By actively integrating general principles that address maintenance error into the design process, it is possible to create design characteristics that can possibly prevent or reduce maintenance error (e.g., sealed units or colour coding) or eliminate or mitigate the consequences of maintenance error (e.g., isolation or partial operation) In developing design strategies and principles that enable the practical realization of these strategies through physical design characteristics, it is 728 C Nicholas important to recognize that error is an integral and important part of fundamental human behavior – it is part of the normal cognitive and learning processes of the human Indeed, error in itself is not inherently problematic It is only problematic when its consequences bring about unwanted or negative consequences Design strategies should therefore attempt to avoid errors or to contain the consequences before they become negative Error in maintenance is a normal part of maintenance operations that can be addressed during the design process Design strategies may revolve around two basic approaches The first is avoidance of error Here the error may be completely avoided by prevention Examples of this type of strategy include designing out operation significant maintenance tasks, the design of components that are physically impossible to assemble or install incorrectly and the use of staggered part positions that require a specific configuration or sealed units that not require intervention It is also possible to reduce the frequency of occurrence of error Examples of error frequency reduction include the use of different part numbers, colour coding, shaped switch tops, locking switches, standard display formats, standard direction of operation, convenient access panels, reduction of servicing frequency, protection against accidental damage, or lubrication points that not require disassembly The second is tolerance of error Here mechanisms to detect error, to reduce the impact of error, and to recover error may be employed Mechanisms to detect error may include built-in tests, functional tests, illuminated test points, functionally grouped tests or warning lights Detection error can also include initial training of the maintainer for system state recognition Reduction of the impact of error can be achieved through strategies such as isolation of the consequences of error, the ability for partial operation or the use of redundancy in systems or components Recovery of error may be achieved through self-correction, the development of recovery procedures or specific training for error recovery Specific design objectives can be summarised as follows: • • • • • Design that absolutely eliminates any possibility of an identified maintenance error or eliminates its consequences; Design that reduces the size of an identified maintenance error or reduces the extent of its consequences; Design that reduces how often an identified maintenance error, or how often its consequences, are likely to occur; Design that ensures that the maintenance error or its consequences is evident under all maintenance conditions, easy and rapid to detect, and is detected before flight; and Design that ensures that following a maintenance error the means to return a system to its correct state are evident, easy, and timely In practice, the strategies of avoidance and tolerance are complementary and it may be felt necessary to design using a combination An error tolerant design may be combined with error avoidance mechanisms to produce a robust design Total avoidance of error may be considered to be an ideal given the nature and variability Human Error in Maintenance – A Design Prospective 729 of human performance – error tolerance will capture and contain errors that fail avoidance mechanisms The general design principles discussed below provide practical means by which these strategies can be realised 26.6.1 Appreciate the Maintainer’s Perspective of the Aircraft Designers design systems or components to deliver their required functionality Maintainers are responsible for maintaining that functionality over the life of the aircraft whilst ensuring safety standards and operational requirements are met As a consequence, maintainers have a very specific perspective of an aircraft that will focus on the efficiency and safety of maintenance Maintainers look for ‘maintainer friendly aircraft’ whose design characteristics enable them to achieve good maintenance performance that delivers the aircraft back into service when required by the operator and that will complete the flight in safety From the maintainer’s perspective therefore questions arise such as: • • • • • • • • • • • • How long will the task take? Is the task complicated? How often is the task required? Do I need special training? Do I need special tools or equipment? Could I make an error? How will I know if things go wrong? Where is the item located on the aircraft? Is there enough space to work in? Can I see the item? Can I reach the item? and Where will I carry out the maintenance? 26.6.2 Design for the Aircraft Maintenance Environment To appreciate fully the impact of design on maintenance performance it is important to understand the environment in which aircraft maintainers work Aircraft maintenance generally takes place under conditions that are complex and very demanding Line maintenance, for example, is generally performed outside the hanger working on the airport ramp or apron area in all types of weather and climate, often at night with limited visibility The environment is extremely busy with aircraft loading and servicing vehicles moving around There is considerable noise and there are fumes from aircraft engines and APUs (auxiliary power units) running Above all there is constant pressure to complete maintenance activities as quickly as possible to turn the aircraft around on time for departure Operators are in the business of transporting passengers Aircraft on the ground cost money and lose revenue for the operator 730 C Nicholas Similarly, base maintenance that is generally carried out in the hanger involves an environment where there is a considerable amount of activity and pressure to get the job done Having to meet exacting work schedules while still observing standard procedures and safety standards can be stressful The hangar is generally noisy from the use of power tools and there are many fluids and substances (hydraulic fluids, cleaning compounds, fuel, paints, etc.) that are potentially dangerous Maintenance is often carried out at night when the aircraft are not in use This means the work requires regular shift working Requirements for overtime working and call-outs are common Maintenance tasks can be physically demanding, involving lifting, working in uncomfortable positions or working at height on scaffolds or cherry pickers (lifts) The aircraft maintenance environment places considerable demands upon the maintainer and upon maintenance performance The physical environment has an impact on maintenance performance through: • • • • • • • • Lighting; Climate (dry or humid climates); Temperature (hot or cold temperatures); Weather (rain, wind, ice, snow, etc.,); Fumes and toxic substances; Noise; Motion; and Vibration Clearly designers cannot directly influence the many factors present in the working environment that will affect maintenance performance However, they can have an impact on maintenance performance by taking them into consideration during the design process and reflecting this in design solutions For example, where maintenance tasks are carried out in extremely low temperatures it is important to consider whether a maintenance task generated by a particular design could be carried out whilst wearing gloves or other protective clothing On aircraft lighting can be used where there are light limitations for critical tasks such as those of critical importance in achieving the necessary standards of maintenance performance to achieve these objectives It is particularly important that the design of a system or component does not infringe normal maintenance practices and the reasonable expectations of the maintainer based on training and experience Maintainers might reasonably expect, for example, that, on a dial, values will increase clockwise Understand inspection; design solutions that consider the physical environment in which maintenance is conducted can reduce the potentially negative impact that it can have on maintenance performance Human Error in Maintenance – A Design Prospective 731 26.6.3 Protect the Aircraft and Protect the Maintainer Design solutions can actively influence both the impact that the maintainer has on the aircraft (e.g., through maintenance error or routine violation of procedures) and the impact that the aircraft has on the maintainer (e.g., through the health and safety effects of aircraft design) Examples of design features that are tolerant to the consequences of maintenance error or resistant to the effects of maintenance activity and maintenance environment include: • • • • • • Designing out safety critical maintenance tasks; Items physically impossible to assemble or install incorrectly; Staggered part positions; Partial operation or redundancy; Shaped switch tops, display formats, direction of operation, etc.; and Warning lights and illuminated test points Examples of design considerations to protect maintenance personnel from risks, hazards, incidents, injuries or illnesses include: • • • • • • Electrical isolation and protection from high voltages; Adequate circuit breakers and fuses; Rounded corners and edges; Warning labels; Hot areas shielded and labelled; and Hazardous substances and radiation not emitted Protecting the maintainer is important not only from a health and safety perspective – demands placed on the maintainer that can be potentially injurious can also lead to the occurrence of maintenance error Design can place undue physical stresses on the maintainer The maintainer may be required to wear cumbersome protective equipment to work in particular areas of the aircraft such as fuel tanks The fatigue that can result could generate error Other stressing design characteristics are those that, for example, involve inadequate lighting, vibration or noise, undue strength requirements for maintenance activities, unusual positions in which to carry out maintenance, or proximity of hot surfaces A maintainer who must work close to heat generating components in a humid environment may rapidly lose body fluid, through perspiration as a result of increasing body temperature, which will seriously affect the ability to function correctly If working close to a hot component, the maintainer must continuously avoid being burned whilst undertaking the maintenance task The presence of such psychological and physical stressors can potentially lead to error Example 26.4: The Boeing 777 Refueling Panel (Sabbagh, 1996) Boeing didn’t think of the fact that existing fuel stands only reached a certain height to fuel under the wings of the airplane The 747 was about as high as the 732 C Nicholas fuel stands could go to reach that fuelling panel, and the panel designed on the 777 was 31 inches higher than the 747 Fuellers got very upset “Have you ever fuelled an airplane in a high wind at O’Hare?” they said: “it’s really uncomfortable.” To go any higher without additional stability would be a safety issue Unless the operators hired personnel who are eight feet tall it wouldn’t work Boeing agreed to move the panel down the wing, closer to the fuselage, and, because the wing is slanted up, by moving it inboard it also came closer to the ground - within six inches of reaching the panel Safety specialists allowed a stool to be put on the top of the fuelling platform to reach the panel 26.6.4 Avoid Complexity of Maintenance Tasks The design of a system or component will impact upon both the cognitive (thinking) and physical (doing) demands of the maintenance task Complexity in design can generate complex maintenance tasks that are difficult to understand and difficult to However, the avoidance of complexity in design need not compromise or constrain the technical design solution The design principle is concerned with the effect that the design has on the maintenance task – an advanced design solution does not necessarily generate complexity in maintenance Example 26.5: Airbus A320 Flap Rotary Actuator (Airbus, 2005) There are four rotary actuators on each wing of the A320 The function of these actuators is to translate the rotary motion of the flap drive shaft into movement of the flaps Following flap lock events, it was reported in several cases that the flap rotary actuators had recently been removed for re-greasing Investigation revealed that, during accomplishment of removal or installation slight mis-rigging in the flap transmission had been induced This was found to be a contributing factor in the reported flap locks Existing flap rotary actuators filled with grease needed removal for re-greasing approximately every years A new type of actuator introduced is filled with semi fluid and is serviceable on the wing The design solution simplified the maintenance task by eliminating the need for removal/installation of the actuators, thereby removing the opportunity for misrigging 26.6.5 Enable Adequate Maintenance Access Accessibility means having adequate visual and physical access to perform maintenance safely and effectively Adequate physical and visual access is needed not only for repair, replacement, servicing, and lubrication but also for troubleshooting, checking and inspection Examples of physical access considerations include: • • Adequate access to frequent maintenance areas; Openings of adequate size; Human Error in Maintenance – A Design Prospective • • • 733 Avoidance of the need to remove a large numbers of components, fittings, etc., to reach a component; Replacement of components with the least amount of handling; and Workspace for manipulative tasks, body and tools positions and movements; Examples of visual access considerations include: • • Avoidance of unnecessary obstructions to the maintainer’s line of sight; and Lighting level and direction Some components by their function or requirements have to be located in poorly accessible areas – a design solution in such cases might be the use of integrated access platforms or other aids to access Example 26.6: B-1B Engine Visual Access (Worm, 1997) Each engine on the B-1B bomber has an accessory drive gearbox (ADG) A hinged access door with four thumb latches is provided on each compartment panel for servicing The access door permits checking of the ADG oil without having to remove the compartment panel However, the oil level sight gauge requires line-ofsight reading Because of the way it is installed, the gauge cannot be read through the access door, even with an inspection mirror The entire compartment panel, secured with 63 fasteners, must be removed just to see if oil servicing is needed 26.6.6 Positively Standardise and Positively Differentiate Aircraft maintenance tasks are largely repetitive and standardised Maintainers rely on pattern recognitions that are determined by their training and experience to identify system and component type properties and the form of the maintenance tasks that are required Commonality in design enables such pattern recognition and enhances maintenance performance If, for example, a part has commonality in function and properties (and, of course, fully meets all requirements of the design specification) then it makes sense from the maintenance perspective to use common parts Similar systems or components with variations in configuration can reduce the effectiveness of maintenance and can be a cause of maintenance error Reenforcement of pattern recognition can also be applied to commonality in maintenance activities If a part does not have commonality with the function and properties of other parts then it makes sense from the maintenance perspective to make the differences obvious This will provide a clear and unambiguous signal to the maintainer that there are differences in maintenance actions 734 C Nicholas Example 26.7: Boeing 777 Door Hinges (Sabbagh, 1996) Early in the design process it was realized that there were three separate hinges that are complex parts In addition, if the hinge came into the door at a different place on each door all the mating, parts would be different It was recognized early on that the key to making all the parts common was to make the hinge common, notwithstanding the fact that the shape of the body was different As a result, not only is the hinge common but so is the complete mechanism Indeed, 98% of all the mechanism of the door is common 26.6.7 Build Error Detection into the Maintenance Process Design solutions can assist in the detection of maintenance error before aircraft dispatch Design can determine how maintenance error is detected and by whom Ideally, maintenance error should be detected before the aircraft is handed back to service after maintenance has been completed In practice, however, the flight crew often detects error either before take off or, worse, in flight Mechanisms to detect error may include built-in tests, functional tests, illuminated test points, functionally grouped tests or warning lights, but equally they can be very simple, such as the use of physical indicators Ambiguous, difficult, complex or lengthy means to detect a maintenance error can affect the likelihood of detection being successful Detection means should ensure that the maintenance error is evident under all maintenance conditions, easy and quick to detect, and detected before flight Example 26.8: JSF Landing Gear Sensors (DSI International, 2004) The Joint Strike Fighter team has broken new ground by the use of landing gear sensors purely on the basis of improving maintenance performance Landing gear present many maintenance problems – one particular problem is measurement of the amount of hydraulic fluid by observation This maintenance task has led to damaged landing gear due to overfilling The JSF programme, on the recommendation of its prognostics team, has agreed to embed sensors in the landing gear in order to report the exact level of hydraulic fluid, and in doing so has avoided maintenance error and saved cost 26.7 Conclusion There is a growing awareness of the vital role that design has to play in influencing maintenance performance and, more specifically, the avoidance or mitigation of maintenance error and its negative effects on safe and effective maintenance activity The maintainer interacts with aircraft systems and components through maintenance tasks that are generated by design characteristics Design will determine the characteristics of the maintenance task and influence the possibility Human Error in Maintenance – A Design Prospective 735 of error occurring – it will also determine the possibility for error avoidance and tolerance This chapter has described an analytical approach and general design principles that can be practically adopted and implemented to develop practicable solutions that address reasonably foreseeable maintenance errors The methodology and principles have been developed from extensive investigation of maintenance error, its causes and consequences specifically to enable the designer to consider the impact of physical design on the behavior of the maintainer The approach taken is deliberately not intended to prescribe design practice, to teach designers how to design, or to advocate further constraints to the design process but rather to add a vitally important dimension to existing knowledge and skills that will enhance maintenance performance and aviation safety References Airbus (2005) FAST Technical Magazine A320 Special, May Boeing Commercial Airplane Group, (2003) Statistical Summary of Commercial Jet Airplane Accidents Worldwide Operations 1959–2002 Air Safety, May CBC, (2005) CBC Canada News Updated 11 March Courteney H (2001) Human Centred Design for Maintenance, UK Civil Aviation Authority, 15th HFIAM Symposium DSI International (2004) A Prognosis Sensor Victory on the Joint Strike Fighter (JSF), November F-16.net (2005) 23 August Flight International (2003) Safety Review Goglia J (2000) Unpublished statements at the 14th Human Factors in Aviation Maintenance Symposium, Vancouver, 2000 and Advances in Aviation Safety Conference, Daytona Beach, 2000 Graeber RC, and Marx DA (1993) Reducing Human Error in Aviation Maintenance Operations, Flight Safety Foundation 46th Annual International Air Safety Seminar, Kuala Lumpur, Malaysia Hessburg J (2001) Air Carrier MRO Handbook, McGraw Hill Marx D (1998) Learning from our Mistakes: A Review of Maintenance Error Investigation and Analysis Systems, FAA, January MEMS-MEDA (2003) Seminar, May 2003 National Transportation Safety Board, United States of America, (2002) Aircraft Accident Report NTSB/AAR-03/02 Reason J (1997) Managing the Risks of Organisational Accidents, Ashgate Royal Aeronautical Society, (2000) The Business Case for Human Factors Programmes in Aviation Maintenance, Royal Aeronautical Society Brainstorming Session, Gatwick, December Sabbagh K (1996) 21st Century Jet – The Making of the Boeing 777, Pan Books Sears RL (1993) A New Look at Accident Contributions and the Implications of Operational Training Programmes (Unpublished Report) in Graeber RC and Marx D, Reducing Human Error in Aviation Maintenance Operations, Flight Safety Foundation Annual International Air Safety Seminar Worm CM (1997) The Real World – A Maintainer’s View, Proceedings IEEE Reliability and Maintainability Symposium, IEEE Index accident, 616 causation, 626 causes, 623 description, 624 examples, 622 industry examples, 624 prevention, 636 rate, 620 reasons, 621 severity, 620 activity-based costing, 128 Agency Theory, 474 analysis of error, 719, 723, 726 worksheet, 719 analysis of suspended data, 70 ARMA, 171 authority, 4, 10, 13, 14 autonomous maintenance, 445 autonomous work teams, 440 autoregressive, 171 availability, 192, 193, 196, 207, 304, 314, 315, 317, 321 availability model, 138 backlog, 108 base warranty, 465 Bayesian parameter estimation, 347 budget breakdown maintenance, 120 capital, 119 cash, 119 committee, 120 cycle, 120 definition, 116 performance, 117 planned maintenance, 120 template, 121 variances, 117 budgetary process, 118 budgeting, 107 capacity planning, definition, 175 formulation, 177 mathematical programming, 180 process, 175 queueing models, 183 simulation, 187 techniques, 176 centralized maintenance, 7, centralized stock, 215 change management, 20 CMMS, 108, 422, 442 co-generation system, 364, 387, 388, 392 combined maintenance task, 579 condition monitoring, 342, 500, 503, 506, 520, 524 condition-based maintenance, 500 control actions, 348, 351 adaptive, 342, 348, 351, 356 algorithms, 350 cost, 109 parameters, 350 process, 96, 339, 350, 356 signals, 351 statistical, 350 steps, 98 strategy, 350, 351 structure, 97 738 Index tools, 107 control barriers, 84 corrective deferred major, 174 corrective deferred minor, 173 corrective emergency, 173 corrective maintenance, 363 cost variance, 129 CPM, 253, 256 Croston method, 199, 200 cumulative damage, 364, 388, 389, 392 cycle average method, 169 data censored, 63 complete, 63 decentralized maintenance, 7, decentralized system, 214 decision support system, 506 Decision Support System, 518 degradation process, 312, 321, 324, 326, 328 Delphi method, 160 Deming’s 14 points, 650, 651, 652 detection, 77 detection evaluation criteria, 81 detection signal, 347 diagnosis and prognosis, 512 discounted Markov decision problem, 270 discounted Markov decision process, 270, 273 distribution binomial, 54 definition, 50 exponential, 60 lognormal, 58 normal, 56 Poisson, 55 Weibull, 61 duration of maintenance task, 566 dynamic programming principle, 276 e-maintenance application, 524, 536 e-maintenance solution, 503, 507, 508, 510, 528, 529, 530, 536, 537 engineering controls, 639 environmental performance, 656 equipment history, 409 ERP, 260 estimation method least squares, 67 maximum likelihood, 69 probability plotting, 64 European Agency for Safety and Health at Work, 643 exponential smoothing double, 166 simple, 165 extended warranty, 467 factor charting, 84 failure detection, 347 failure effect, 77 failure mode, 77 failure modes, 398, 400, 405 failure rate, 52 fault diagnosis, 356 techniques, 350 fault diagnosis and detection, 349 Fault Tree Analysis, 638 feedback, 99 FEMA, 410 FIMS, 107 FMEA, 638 forecasting model steps, 158 forecasting techniques, 158 free replacement warranty, 466 full authority digital electronic control, 363 full authority digital engine controller, 380, 381, 385 functional block diagram, 407 functional failure, 398, 405, 410 functionality, 548 functions, 6, 9, 15 Gantt chart, 250 hazard, 616 classes, 619 hazard prevention, 638 health monitoring, 537 history file, 103 Holt’s method, 166 human error, 712, 713, 718, 724, 726 consequence, 700 in maintenance, 625 influencing factors, 626 reasons, 701 reduction, 707 human errors categories, 625 classification, 700 Index human performance reliability, 699 imperfect repair, 468 incentives, 4, 13 indices maintenance, 96 production, 96 industrial hazard avoidance, 637 in-house maintenance, 4, 6, inspection, 365, 366, 367, 370, 372, 482 alarm threshold, 323 basic model, 305 conditional, 322 degradation process, 324 example, 493 imperfect, 485 modeling, 483 multi-componenet system, 318 policies, 311 perfect, 484 intelligent maintenance system, 500, 506, 510, 511, 537 International Labour Organization, 643 inventory control, 199 control policies, 201 models, 202 parameters, 201 policies, 205 pooling, 214, 215 spare parts, 213 job card, 102 job cost sheet, 125 joint optimization of maintenance and inventory, 205 joint replenishment, 214 spare parts, 216 labor relations, 5, 14 LCC, 108 leadership, 4, 13 life cycle costing, 634 likelihood function, 487, 489, 491, 492, 494 logic tree analysis, 412 maintainability analysis, 561 concept, 549, 550 definition, 551 design issues, 596 739 design review, 587 desirable practices, 559 economic impact, 554 engineering, 572 engineering management function, 592, 593 engineering predictions, 577 function, 565, 567, 574, 582, 586 function derivation, 580 impact of system effectiveness, 552 impact on safety, 555 lessons learned, 603 measures, 568, 571, 581, 583 parametric approach, 572 statistics, 561, 572 undesirable practices, 558 maintainability block diagram, 577 maintainability data distribution approach, 572 maintenance error causes, 724 definition, 712 design, 717 detection, 719 examples, 713, 714, 715, 722, 734 mitigation, 727, 731 reasons, 712 safety impact, 713 maintenance error analysis, 702 maintenance models, 363 maintenance performance, 138, 146 maintenance philosophies, 340 maintenance prevention, 421, 449 maintenance strategy, 138, 142, 152, 243 maintenance system audit, 655 Markov decision problem, 279 Markovian jumps, 275 maximum likelihood method, 135 mean absolute deviation, 172 mean absolute percent error, 172 mean duration of maintenance task, 566, 575 mean squared error, 172 mean time between failure, 53 Mean Time Between Maintenance, 569 Mean Time Between Replacements, 569 median rank, 65 missile, 364, 365, 373 model based approaches, 344 moral hazard, 474 moving average, 162 model, 171 740 Index simple, 162 weighted, 162 MPIs auto industry, 38, 39 categories, 29 definition, 24 development, 25 oil industry, 35 process industry, 37 selection, 26 specifying, 26 testing, 29 utility industry, 37 MPM implementation, 29, 31 issues, 25 multi-criteria, 31 oil industry, 35 process industry, 37 system, 27 MTBM See Mean Time Between Maintenance MTBR See Mean Time Between Replacements neural networks, 344, 347, 350, 353 occupational safety, 613, 620, 632, 642, 643 occupational stressors, 697 occurrence, 77 occurrence evaluation criteria, 79 OEE, 110, 426 OPTIMAIN, 134, 141, 150, 152 optimal control problem, 268 organization structure, 3, 6, 15 design, 4, 8, 15 hybrid, 7, 10 matrix, 10, 12 organizational change, OSHA, 642 outsourcing, 4, 6, 7, 15, 242 parameter estimation, 64,345 parity space relations, 346 patterns, 159 percentage restoration time, 574 percentual duration of maintenance task, 566 performance indicators, 22, 33, 34, 36, 661 personal protective clothing and/or equipment, 640 PERT, 253, 258 phased array radar, 364, 373, 374, 377 planner qualifications, 247 planning and forecasting, 98 planning horizon, 237 planning procedure, 246 planning sheet, 248 PM task selection, 411 PPE See personal protective clothing and/or equipment predictive maintenance, 400, 420 preventive maintenance, 363, 420 productive maintenance, 421 productivity measurement, 21, 22 measurement factors, 23, 24 prognostic approach, 502 prognostic systems, 348, 356 proportional hazards modeling, 347 quality policy, 231 RCM, 342, 421, 635 RCM process, 398, 400, 411 regression method, 134, 135 regression models, 163 reliability estimation, 134, 152 reliability function, 52 reliability model estimation, 138 repeat jobs, 109 replacement at pro-rata cost, 466 residual generation, 345 responsibility, 5, 6, 13 risk pooling, 215 root cause analysis, 638 run to failure, 400 safe maintenance practices, 639 safety culture, 641 safety legislation, 642 safety monitoring, 232 safety performance indicators, 645 safety performance measurement, 644 safety policy, 231 sales force composite, 160 scheduling definition, 237, 247 elements, 249 objectives, 239 procedure, 249 Index seasonal factors, 169 sequential maintenance task, 579 service delivery, 471 service level, 198, 200, 215 severity, 77 severity evaluation criteria, 80 signal-based FDI, 346 simulation model, 134, 143,144, 150,151 spare part inventories, 473 spare parts centralization, 215 characteristics, 191 classification, 193 forecasting, 198 identification, 192 joint ordering, 216 kit, 192 maintenance, 212 optimal quantity, 195, 202 quantity, 193 reconditioned, 210 replacement, 207 virtually centralized, 214 spare parts management, 4, 10 standby systems, 319 state trajectories, 276 stationarity, 159 stimuli, 616 strategic planning process, 243 supervision, 4, 5, 7, 13 sustainability business, 672 compliance, 671, 676, 687 drivers, 674 issues, 673 maintenance impact, 679 performance, 678 risk, 687 sustainability performance measurement, 670 sustainable asset maintenance, 667 system boundary, 407 system function, 398, 400, 401, 405, 407, 409, 410 741 system interfaces, 408 TAM phases, 225 time-frequency analysis, 347 TPM, 635, 650 benchmark indices, 451 definition, 418 implementation, 429 KPI, 451 lean practices, 452 methodology, 435 need, 423 obstacles, 453 safety, 449 success factors, 456 tools, 425 training, 4, 7, 10, 14 types of censored data, 64 types of FMEA, 79 vibration monitoring, 350 visual workplace, 442 WAN, 507, 510 warranty and maintenance, 467 warranty logistics, 472 warranty servicing model, 468 watchdog agent, 510, 512, 514, 518, 525, 532, 536 wear, 323 web-based solutions, 505 wide-area networks, 505 work measurement, 107 work order flow, 105 form, 100 information, 101 planning, 98 system, 99 work package, 227 working relations chain of command, delegation of authority, .. .Handbook of Maintenance Management and Engineering Mohamed Ben-Daya • Salih O Duffuaa Abdul Raouf • Jezdimir Knezevic • Daoud Ait-Kadi Editors Handbook of Maintenance Management and Engineering. .. this handbook cover a wide range of issues in the area of maintenance management and engineering to cater for all those interested in maintenance whether practitioners or researchers This handbook. .. parts and contains 26 chapters covering a wide range of topics related to maintenance management and engineering Part I deals with maintenance organization and performance measurement and contains