The impact of reliability centered maintenance on plant prospects for license renewal

International Nuclear Information System (INIS)

Elliott, J.O.; Nakahara, Y.

1991-01-01

Much attention has been directed in recent years to means of extending nuclear power plant life. As many plants enter their third decade of service, the questions loom large of how to keep aging plants reliable, as well as how to assure reliability and safety to an extent sufficient to warrant license renewal at the end of the current licensing term. Concurrently the nuclear industry has seen a growing interest in reducing the cost and complexity of maintenance activities while at the same time improving plant reliability and availability. Attainment of these seemingly contradictory aims is being aided by the introduction of a maintenance philosophy developed originally by the airline industry and subsequently applied with great success both in that industry and the U.S. military services. Reliability Centered Maintenance (RCM), in its basic form, may be described as a consideration of reliability and maintenance problems from a systems level approach, allowing a focus on preservation of system functions as the aim of a maintenance program optimized for both safety and economics. It is this systematic view of plant maintenance, with the emphasis on preservation of overall functions rather than individual parts and components which sets RCM apart from past nuclear plant maintenance philosophies. It is also the factor which makes application of RCM an ideal first step in development of strategies for life extension and license renewal, both for aging plants, and for plants just beginning their first license term

Reliability Centered Maintenance for Savannah River Site's interim waste management facilities

International Nuclear Information System (INIS)

Hauer, K.A.; Wilson, J.F.

1992-01-01

The application of Reliability Centered Maintenance (RCM) has been shown to be an effective means to optimize maintenance programs or to establish new programs. The key to success of any RCM program is to customize the methodology to meet the specific needs of the implementing organization. This paper discusses how RCM is being used to establish the preventive maintenance program and how the resulting system data is being used to support the Technical Baseline reconstitution effort for the interim Waste Management Division of Westinghouse Savannah River Company (WSRC)

The advantages of reliability centered maintenance for standby safety systems

International Nuclear Information System (INIS)

Dam, R.F.; Ayazzudin, S.; Nickerson, J.H.; DeLong, A.I.

2002-01-01

Full text: On standby safety systems, nuclear plants have to balance the requirements of demonstrating the reliability of each system, while maintaining the system and plant availability. With the goal of demonstrating statistical reliability, these systems have extensive testing programs, which often makes the system unavailable and this can impact the plant capacity. The inputs to the process are often safety and regulatory related, resulting in programs that provide a high level of scrutiny on the systems being considered. In such cases, the value of the application of a maintenance optimization strategy, such as Reliability Centered Maintenance (RCM), is questioned. Part of the question stems from the use of the word 'Reliability' in RCM, which implies a level of redundancy when applied to a system maintenance program driven by reliability requirements. A deeper look at the RCM process, however, shows that RCM has the goal of ensuring that the system operates 'reliably' through the application of an integrated maintenance strategy. This is a subtle, but important distinction. Although the system reliability requirements are an important part of the strategy evaluation, RCM provides a broader context where testing is only one part of an overall strategy focused on ensuring that component function is maintained through a combination of monitoring technologies (including testing), predictive techniques, and intrusive maintenance strategies. Each strategy is targeted to identify known component degradation mechanisms. The conclusion is that a maintenance program driven by reliability requirements will tend to have testing defined at a frequency intended to support the needed statistics. The testing demonstrates that the desired function is available today. Maintenance driven by functional requirements and known failure causes, as developed through an RCM assessment, will have frequencies tied to industry experience with components and rely on a higher degree of

Applying reliability centered maintenance analysis principles to inservice testing

International Nuclear Information System (INIS)

Flude, J.W.

1994-01-01

Federal regulations require nuclear power plants to use inservice test (IST) programs to ensure the operability of safety-related equipment. IST programs are based on American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code requirements. Many of these plants also use Reliability Centered Maintenance (RCM) to optimize system maintenance. ASME Code requirements are hard to change. The process for requesting authority to use an alternate strategy is long and expensive. The difficulties of obtaining this authority make the use of RCM method on safety-related systems not cost effective. An ASME research task force on Risk Based Inservice Testing is investigating changing the Code. The change will allow plants to apply RCM methods to the problem of maintenance strategy selection for safety-related systems. The research task force is working closely with the Codes and Standards sections to develop a process related to the RCM process. Some day plants will be able to use this process to develop more efficient and safer maintenance strategies

A Simulation Model for Machine Efficiency Improvement Using Reliability Centered Maintenance: Case Study of Semiconductor Factory

Directory of Open Access Journals (Sweden)

Srisawat Supsomboon

2014-01-01

Full Text Available The purpose of this study was to increase the quality of product by focusing on the machine efficiency improvement. The principle of the reliability centered maintenance (RCM was applied to increase the machine reliability. The objective was to create preventive maintenance plan under reliability centered maintenance method and to reduce defects. The study target was set to reduce the Lead PPM for a test machine by simulating the proposed preventive maintenance plan. The simulation optimization approach based on evolutionary algorithms was employed for the preventive maintenance technique selection process to select the PM interval that gave the best total cost and Lead PPM values. The research methodology includes procedures such as following the priority of critical components in test machine, analyzing the damage and risk level by using Failure Mode and Effects Analysis (FMEA, calculating the suitable replacement period through reliability estimation, and optimizing the preventive maintenance plan. From the result of the study it is shown that the Lead PPM of test machine can be reduced. The cost of preventive maintenance, cost of good product, and cost of lost product were decreased.

Identification of tasks of maintenance centered in the reliability

International Nuclear Information System (INIS)

Torres V, A.; Rivero O, J.J.

2004-01-01

The methodology of Reliability Centered Maintenance (RCM) it has become, after the discovery of their advantages, an objective of many industrial facilities to optimize their maintenance. However, diverse subjective factors affect the determination of the parameters (technical of predictive to apply and times among interventions) that characterize the tasks of RCM. A method to determine the monitoring tasks at condition and the times more recommended for to apply the monitoring by time and the search of faults, with focus in system. This methodology has been computerized inside the code MOSEG Win Ver 1.0. The same has been applied with success to the determination of tasks of RCM in industrial objectives. (Author)

Building and integrating reliability models in a Reliability-Centered-Maintenance approach

International Nuclear Information System (INIS)

Verite, B.; Villain, B.; Venturini, V.; Hugonnard, S.; Bryla, P.

1998-03-01

Electricite de France (EDF) has recently developed its OMF-Structures method, designed to optimize preventive maintenance of passive structures such as pipes and support, based on risk. In particular, reliability performances of components need to be determined; it is a two-step process, consisting of a qualitative sort followed by a quantitative evaluation, involving two types of models. Initially, degradation models are widely used to exclude some components from the field of preventive maintenance. The reliability of the remaining components is then evaluated by means of quantitative reliability models. The results are then included in a risk indicator that is used to directly optimize preventive maintenance tasks. (author)

Development of reliability centered maintenance methods and tools

International Nuclear Information System (INIS)

Jacquot, J.P.; Dubreuil-Chambardel, A.; Lannoy, A.; Monnier, B.

1992-12-01

This paper recalls the development of the RCM (Reliability Centered Maintenance) approach in the nuclear industry and describes the trial study implemented by EDF in the context of the OMF (RCM) Project. The approach developed is currently being applied to about thirty systems (Industrial Project). On a parallel, R and D efforts are being maintained to improve the selectivity of the analysis methods. These methods use Probabilistic Safety Study models, thereby guaranteeing better selectivity in the identification of safety critical elements and enhancing consistency between Maintenance and Safety studies. They also offer more detailed analysis of operation feedback, invoking for example Bayes' methods combining expert judgement and feedback data. Finally, they propose a functional and material representation of the plant. This dual representation describes both the functions assured by maintenance provisions and the material elements required for their implementation. In the final chapter, the targets of the future OMF workstation are summarized and the latter's insertion in the EDF information system is briefly described. (authors). 5 figs., 2 tabs., 7 refs

Decreasing inventory of a cement factory roller mill parts using reliability centered maintenance method

Science.gov (United States)

Witantyo; Rindiyah, Anita

2018-03-01

According to data from maintenance planning and control, it was obtained that highest inventory value is non-routine components. Maintenance components are components which procured based on maintenance activities. The problem happens because there is no synchronization between maintenance activities and the components required. Reliability Centered Maintenance method is used to overcome the problem by reevaluating maintenance activities required components. The case chosen is roller mill system because it has the highest unscheduled downtime record. Components required for each maintenance activities will be determined by its failure distribution, so the number of components needed could be predicted. Moreover, those components will be reclassified from routine component to be non-routine component, so the procurement could be carried out regularly. Based on the conducted analysis, failure happens in almost every maintenance task are classified to become scheduled on condition task, scheduled discard task, schedule restoration task and no schedule maintenance. From 87 used components for maintenance activities are evaluated and there 19 components that experience reclassification from non-routine components to routine components. Then the reliability and need of those components were calculated for one-year operation period. Based on this invention, it is suggested to change all of the components in overhaul activity to increase the reliability of roller mill system. Besides, the inventory system should follow maintenance schedule and the number of required components in maintenance activity so the value of procurement will be decreased and the reliability system will increase.

Reliability Centered Maintenance for Savannah River Site's interim waste management facilities

Energy Technology Data Exchange (ETDEWEB)

Hauer, K.A. (Westinghouse Savannah River Co., Aiken, SC (United States)); Wilson, J.F. (PRC, Inc. (US))

1992-01-01

The application of Reliability Centered Maintenance (RCM) has been shown to be an effective means to optimize maintenance programs or to establish new programs. The key to success of any RCM program is to customize the methodology to meet the specific needs of the implementing organization. This paper discusses how RCM is being used to establish the preventive maintenance program and how the resulting system data is being used to support the Technical Baseline reconstitution effort for the interim Waste Management Division of Westinghouse Savannah River Company (WSRC).

Reliability centered maintenance as an optimization tool for electrical power plants

International Nuclear Information System (INIS)

Jacquot, J.P.; Bryla, P.; Martin-Mattei, C.; Meuwisse, C.

1997-08-01

Seven years ago, Electricite de France launched a Reliability Centered Maintenance (RCM) pilot project to optimize preventive maintenance for its nuclear power plants. After a feasibility study, a RCM method was standardized. It is now applied on a large scale to the 50 EDF nuclear units. A RCM workstation based on this standardized method has been developed and is now used in each plant. In the next step, it is considered whether a Risk based Approach can be included in this RCM process in order to analyze critical passive components such as pipes and supports. Considering the potential advantages of these optimization techniques, a dedicated process has been also developed for maintenance of future plants, gas turbines, or nuclear units. A survey of these different developments of methods and tools is presented. (author)

Optimization of Reliability Centered Maintenance Bassed on Maintenance Costs and Reliability with Consideration of Location of Components

Directory of Open Access Journals (Sweden)

Mahdi Karbasian

2011-03-01

Full Text Available The reliability of designing systems such as electrical and electronic circuits, power generation/ distribution networks and mechanical systems, in which the failure of a component may cause the whole system failure, and even the reliability of cellular manufacturing systems that their machines are connected to as series are critically important. So far approaches for improving the reliability of these systems have been mainly based on the enhancement of inherent reliability of any system component or increasing system reliability based on maintenance strategies. Also in some of the resources, only the influence of the location of systems' components on reliability is studied. Therefore, it seems other approaches have been rarely applied. In this paper, a multi criteria model has been proposed to perform a balance among a system's reliability, location costs, and its system maintenance. Finally, a numerical example has been presented and solved by the Lingo software.

ANALISIS MODA KEGAGALAN DENGAN PENDEKATAN RELIABILITY CENTERED MAINTENANCE (RCM (Studi kasus Baking Section Mesin Imfori PT Nissin Biskuit Indonesia

Directory of Open Access Journals (Sweden)

Sri Hartini

2012-02-01

Full Text Available Reliability Centered Maintenance (RCM adalah suatu pendekatan perawatan yang berbasis pada upaya menjamin keandalan mesin. Dengan pendekatan ini, perawatan ditujukan untuk menjamin agar asset terus menerus mencapai kemampuan dasarnya. Dalam penelitian dilakukan analisis fungsi sistem yang tepat terhadap Baking Section mesin Imaforni PT Nissin Biskuit Indonesia melalui pendekatan RCM untuk mengetahui moda kegagalan yang dapat menyebabkan sistem kehilangan fungsinya. Kata Kunci : Fungsi Sistem,Moda Kegagalan,Reliability Centered Maintenance.

A reliability centered maintenance model applied to the auxiliary feedwater system of a nuclear power plant

International Nuclear Information System (INIS)

Araujo, Jefferson Borges

1998-01-01

The main objective of maintenance in a nuclear power plant is to assure that structures, systems and components will perform their design functions with reliability and availability in order to obtain a safety and economic electric power generation. Reliability Centered Maintenance (RCM) is a method of systematic review to develop or optimize Preventive Maintenance Programs. This study presents the objectives, concepts, organization and methods used in the development of RCM application to nuclear power plants. Some examples of this application are included, considering the Auxiliary Feedwater System of a generic two loops PWR nuclear power plant of Westinghouse design. (author)

Reliability Centered Maintenance for Savannah River Site`s interim waste management facilities. Revision 1

Energy Technology Data Exchange (ETDEWEB)

Hauer, K.A. [Westinghouse Savannah River Co., Aiken, SC (United States); Wilson, J.F. [PRC, Inc. (US)

1992-06-01

The application of Reliability Centered Maintenance (RCM) has been shown to be an effective means to optimize maintenance programs or to establish new programs. The key to success of any RCM program is to customize the methodology to meet the specific needs of the implementing organization. This paper discusses how RCM is being used to establish the preventive maintenance program and how the resulting system data is being used to support the Technical Baseline reconstitution effort for the interim Waste Management Division of Westinghouse Savannah River Company (WSRC).

Hardware-oriented reliability centered maintenance for the diesel generators of Wolsong unit 1

International Nuclear Information System (INIS)

Bae, Sang Min; Park, Jin Hee; Kim, Tae Woon; Lee, Yoon Kee; Song, Jin Bae

1997-01-01

The DGs (Diesel Generators) in NPP (Nuclear Power Plant) has been used for the emergency electric power source to shut down the nuclear reactor safely in case of station blackout. The RCM (Reliability Centered Maintenance) has been applied to DGs for increasing the safety of NPP. The structured defects of DG were not remedied by the improvement of maintenance method. As the first stage of RCM, to find the structured defects, its failure modes were searched and analyzed through the ten year maintenance information. The structured defects such as the air compressor, the lubricating oil pressure, and the insufficient load were the root causes of main failures. The air reservoir reinstallation, the lubricating oil tube modification, the load bank installation, and the qualitative instrumentation were the solutions for the hardware oriented RCM of DGs. There remains the software oriented RCM such as the rejection of useless maintenance, the preventive maintenance, the database of maintenance information, and the predictive maintenance

PERENCANAAN PEMELIHARAAN MESIN BALLMILL DENGAN BASIS RCM (RELIABILITY CENTERED MAINTENANCE

Directory of Open Access Journals (Sweden)

Ahmad Kholid Alghofari

2006-12-01

Full Text Available Aktifitas produksi sering mengalami hambatan dikarenakan tidak berfungsinya mesin-mesin produksi yang dalam industri manufaktur merupakan komponen utama. Kegagalan beroperasi mesin mengakibatkan downtime yang ujung-ujungnya menurunkan produktifitas perusahaan. Oleh karenanya diperlukan sebuah sistem perencanaan pemeliharaan agar menghasilkan availability (ketersediaan mesin yang optimal. Perusahaan yang dijadikan proyek penelitian adalah PT. Sici Multi IndoMarmer yang merupakan perusahaan yang bergerak dalam bidang produksi keramik (kloset jongkok, kloset duduk, washtafel, tempat sabun dimana sistem pemeliharaan mesin, khususnya mesin ballmill yang telah dilakukan masih bersifat corrective maintenance. Tujuan dari penelitian ini adalah implementasi RCM (reliability centered maintenance untuk dapat menentukan pemeliharan yang optimal serta dapat memprediksikan langkah untuk mengatasi kerusakan yang mungkin terjadi pada periode berikutnya berdasarkan data-data yang ada. Dari pengolahan data dan analisa diperoleh komponen-komponen yang paling sering mengalami kerusakan pada mesin ballmill , penyebab kegagalan, keputusan seleksi dan rekomendasi yang dianjurkan untuk sistem pemeliharaan dengan basis RCM.

Reliability and risk treatment centered maintenance

International Nuclear Information System (INIS)

Pexa, Martin; Hladik, Tomas; Ales, Zdenek; Legat, Vaclav; Muller, Miroslav; Valasek, Petr; Havlu, Vit

2014-01-01

We propose a new methodology for application of well-known tools - RCM, RBI and SIF pro - with the aim to treat risks by means of suitable maintenance. The basis of the new methodology is the complex application of all three methods at the same time and not separately as is typical today. The proposed methodology suggests having just one managing team for reliability and risk treatment centred maintenance (RRTCM), employing existing RCM, RBI, and SIFpro tools concurrently. This approach allows for significant reduction of engineering activities' duration. In the proposed methodology these activities are staged into five phases and structured to eliminate all duplication resulting from separate application of the three tools. The newly proposed methodology saves 45% to 50% of the engineering workload and dequate significant financial savings.

Reliability and risk treatment centered maintenance

Energy Technology Data Exchange (ETDEWEB)

Pexa, Martin; Hladik, Tomas; Ales, Zdenek; Legat, Vaclav; Muller, Miroslav; Valasek, Petr [Czech University of Life Sciences Prague, Kamycka (Czech Republic); Havlu, Vit [Unipetrol A. S, Prague (Czech Republic)

2014-10-15

We propose a new methodology for application of well-known tools - RCM, RBI and SIF pro - with the aim to treat risks by means of suitable maintenance. The basis of the new methodology is the complex application of all three methods at the same time and not separately as is typical today. The proposed methodology suggests having just one managing team for reliability and risk treatment centred maintenance (RRTCM), employing existing RCM, RBI, and SIFpro tools concurrently. This approach allows for significant reduction of engineering activities' duration. In the proposed methodology these activities are staged into five phases and structured to eliminate all duplication resulting from separate application of the three tools. The newly proposed methodology saves 45% to 50% of the engineering workload and dequate significant financial savings.

An evaluation of the Browns Ferry Nuclear Plant preventive maintenance program based on reliability centered maintenance analysis

International Nuclear Information System (INIS)

McCullough, C.L.; McCullough, C.A.

1989-01-01

Reliability centered maintenance (RCM) techniques were used to support a preventative maintenance (PM) upgrade program (PMUP) performed at TVA Browns Ferry Nuclear Plant (BFNP). The purpose of the RCM analysis was to identify critical equipment based on risk and economic importance and to evaluate the PM activities applicable to that equipment. The analysis may be conveniently divided into three steps, which will be outlined in the Approach section of this paper. The net benefit of the RCM approach was a prioritization of the focus of the PM upgrade program so that plant components receive attention proportional to their importance, and assurance that PM activities properly address the most likely component failure causes

Guide for monitoring effectiveness of utility Reliability Centered Maintenance (RCM) programs

International Nuclear Information System (INIS)

Midgett, W.D.; Wilson, J.F.; Krochmal, D.F.; Owsenek, L.W.

1991-02-01

Reliability centered maintenance (RCM) programs help utilities optimize preventive maintenance efforts while improving plant safety and economy through increased dependability of plant components. The project team developed this guide and accompanying methodology based on status updates from the Ginna and San Onofre demonstration projects. These updates addressed areas ranging from system selection to the effectiveness of RCM program implementation. In addition, the team incorporated information from a 12-utility survey soliciting opinions on the need for a methodology to monitor RCM cost-effectiveness. An analysis of the 12-utility survey showed that no techniques had been developed to measure RCM program cost-effectiveness. Thus, this guide addresses two key areas: Pros and cons of various monitoring techniques available to assess the overall effectiveness of RCM and a methodology for specifically evaluating the cost-effectiveness of RCM programs. 1 fig

A framework for intelligent reliability centered maintenance analysis

International Nuclear Information System (INIS)

Cheng Zhonghua; Jia Xisheng; Gao Ping; Wu Su; Wang Jianzhao

2008-01-01

To improve the efficiency of reliability-centered maintenance (RCM) analysis, case-based reasoning (CBR), as a kind of artificial intelligence (AI) technology, was successfully introduced into RCM analysis process, and a framework for intelligent RCM analysis (IRCMA) was studied. The idea for IRCMA is based on the fact that the historical records of RCM analysis on similar items can be referenced and used for the current RCM analysis of a new item. Because many common or similar items may exist in the analyzed equipment, the repeated tasks of RCM analysis can be considerably simplified or avoided by revising the similar cases in conducting RCM analysis. Based on the previous theory studies, an intelligent RCM analysis system (IRCMAS) prototype was developed. This research has focused on the description of the definition, basic principles as well as a framework of IRCMA, and discussion of critical techniques in the IRCMA. Finally, IRCMAS prototype is presented based on a case study

The engine maintenance scheduling by using reliability centered maintenance method and the identification of 5S application in PT. XYZ

Science.gov (United States)

Sembiring, N.; Panjaitan, N.; Saragih, A. F.

2018-02-01

PT. XYZ is a manufacturing company that produces fresh fruit bunches (FFB) to Crude Palm Oil (CPO) and Palm Kernel Oil (PKO). PT. XYZ consists of six work stations: receipt station, sterilizing station, thressing station, pressing station, clarification station, and kernelery station. So far, the company is still implementing corrective maintenance maintenance system for production machines where the machine repair is done after damage occurs. Problems at PT. XYZ is the absence of scheduling engine maintenance in a planned manner resulting in the engine often damaged which can disrupt the smooth production. Another factor that is the problem in this research is the kernel station environment that becomes less convenient for operators such as there are machines and equipment not used in the production area, slippery, muddy, scattered fibers, incomplete use of PPE, and lack of employee discipline. The most commonly damaged machine is in the seed processing station (kernel station) which is cake breaker conveyor machine. The solution of this problem is to propose a schedule plan for maintenance of the machine by using the method of reliability centered maintenance and also the application of 5S. The result of the application of Reliability Centered maintenance method is obtained four components that must be treated scheduled (time directed), namely: for bearing component is 37 days, gearbox component is 97 days, CBC pen component is 35 days and conveyor pedal component is 32 days While after identification the application of 5S obtained the proposed corporate environmental improvement measures in accordance with the principles of 5S where unused goods will be moved from the production area, grouping goods based on their use, determining the procedure of cleaning the production area, conducting inspection in the use of PPE, and making 5S slogans.

Suncor maintenance and reliability

Energy Technology Data Exchange (ETDEWEB)

Little, S. [Suncor Energy, Calgary, AB (Canada)

2006-07-01

Fleet maintenance and reliability at Suncor Energy was discussed in this presentation, with reference to Suncor Energy's primary and support equipment fleets. This paper also discussed Suncor Energy's maintenance and reliability standard involving people, processes and technology. An organizational maturity chart that graphed organizational learning against organizational performance was illustrated. The presentation also reviewed the maintenance and reliability framework; maintenance reliability model; the process overview of the maintenance and reliability standard; a process flow chart of maintenance strategies and programs; and an asset reliability improvement process flow chart. An example of an improvement initiative was included, with reference to a shovel reliability review; a dipper trip reliability investigation; bucket related failures by type and frequency; root cause analysis of the reliability process; and additional actions taken. Last, the presentation provided a graph of the results of the improvement initiative and presented the key lessons learned. tabs., figs.

Status of the reliability centered maintenance program at Ontario Hydro's Bruce 'A' Nuclear Division

International Nuclear Information System (INIS)

Khan, I.

1995-01-01

Bruce A started a preventive maintenance (PM) quality improvement program in August of 1991. This initiative was taken to address the concerns expressed by the AECB and the Peer Audits finding. The concerns were on the quality of the Bruce A PM Program and its execution in the field. Reliability Centered Maintenance (RCM) analysis was selected as the PM program quality improvement and optimization technique. Therefore, RCM became a key component of Bruce A's Integrated PM program and maintenance strategy. As a result of RCM implementation, and improvements in the work planning and scheduling process, Bruce A is seeing downward trends in the corrective maintenance work load, maintenance preventable forced outages, overdue/missed PM tasks and corrective maintenance backlog. Control Room Operators have reported observing an improvement in systems and equipment response to transients. Other benefits include a documented, controlled and traceable PM program. In addition, the team approach required by RCM has started to improve staff confidence in the PM program which, in turn, is improving the compliance with the PM program. (author)

Large-scale demonstration of reliability centered maintenance at two nuclear generating stations

International Nuclear Information System (INIS)

Gaertner, J.P.; Edgar, C.; Rodin, M.E.

1989-01-01

This paper reports that after successful single-system pilot applications of Reliability Centered Maintenance (RCM) at various utilities, EPRI with Rochester Gas and Electric and Southern California Edison is undertaking multiple-system applications of RCM at their respective nuclear plants. The objective is to demonstrate the feasibility and cost-effectiveness of large-scale RCM application. In addition, each utility has plant-specific objectives to improve maintenance and plant availability. Each project has selected a prioritized list of some 15-20 systems on which to perform RCM. Each project is employing somewhat different RCM analysis methods, both of which conform to a global RCM definition applicable to all EPRI RCM work to date. Each project has developed important insights for improving cost and value of future analyses. Both projects will have applied the RCM process, including implementation, on several plant systems by April 1989

Failure analysis – basic step of applying Reliability Centered Maintenance in general aviation

Directory of Open Access Journals (Sweden)

Martin BUGAJ

2012-01-01

Full Text Available Performing a reliability analysis on a product or system can actually include a number of different analyses to determine how reliable the product or system is. A reliability centered maintenance program consists of a set of scheduled tasks generated on the basis of specific reliability characteristics of the equipment they are designed to protect. Complex equipment is composed of a vast number of parts and assemblies. All these items can be expected to fail at one time or another, but some of the failures have more serious consequences than others. Certain kinds of failures have a direct effect on operating safety, and others affect the operational capability of the equipment. The consequences of a particular failure depend on the design of the item and the equipment in which it is installed. Although the environment in which the equipment is operated is sometimes an additional factor, the impact of failures on the equipment, and hence their consequences for the operating organization, are established primarily by the equipment designer. Failure consequences are therefore a primary inherent reliability characteristic.

Application of reliability centered maintenance for nuclear power station in Japan

International Nuclear Information System (INIS)

Kumano, Haruyuki; Honda, Hironobu.

1990-01-01

The reliability centered maintenance (RCM) method has been widely used with good results in aviation companies in the U.S. to ensure positive preventive maintenance and management. In addition, the Electric Power Research Institute has been making studies and tests in an effort to apply the RCM method to nuclear power plants. The present report shows and discusses some results of a preliminary study aimed at the introduction of the RCM method to nuclear power plants in Japan. The history of the development and application of RCM is outlined first, and the procedure of its implementation is then described and discussed. The procedure consists of five major steps: collection of data, identification of system components, analysis of the functions of the system, selection of required tasks for preventive management, and packaging. Some actual examples of the application of RCM to nuclear power plants in the U.S. are described. And finally, the report discusses some major problems to be solved to permit the application of RCM to nuclear power plants in Japan. (N.K.)

A study of adopting maintenance rule under the periodic safety review and reliability centered maintenance program

International Nuclear Information System (INIS)

Kilyoo, Kim

2001-01-01

U.S Maintenance Rule (MR) has three main functions. One is to monitor the performance changes of SSCs (Structure, System, and Component) caused by risk informed applications. Periodic Safety Review (PSR) program is widely adopted in Europe while it is not adopted in U. S. A where MR and new oversight program are instead used. Recently, in Korea, it was determined to adopt PSR, and the first PSR program has started this year for Kori unit 1 as a pilot plant. Also, a traditional Reliability Centered Maintenance (RCM) has been performed for 4 systems of YGN unit 1 and 2 and it will be applied to the other nuclear power plants in Korea. However, since MR is adopting many useful concept of RCM, traditional RCM could not be further performed without being associated with MR. Thus, MR, RCM and PSR have recently become hot issue policies which should be well associated each other in Korea, and this paper suggests a desirable new maintenance process which would embrace the concepts of the three policies, and also discusses whether U.S. MR is necessary even though a PSR program is already adopted, and if necessary, then how cost-effectively it can be introduced to. (author)

A New Biobjective Model to Optimize Integrated Redundancy Allocation and Reliability-Centered Maintenance Problems in a System Using Metaheuristics

Directory of Open Access Journals (Sweden)

Shima MohammadZadeh Dogahe

2015-01-01

Full Text Available A novel integrated model is proposed to optimize the redundancy allocation problem (RAP and the reliability-centered maintenance (RCM simultaneously. A system of both repairable and nonrepairable components has been considered. In this system, electronic components are nonrepairable while mechanical components are mostly repairable. For nonrepairable components, a redundancy allocation problem is dealt with to determine optimal redundancy strategy and number of redundant components to be implemented in each subsystem. In addition, a maintenance scheduling problem is considered for repairable components in order to identify the best maintenance policy and optimize system reliability. Both active and cold standby redundancy strategies have been taken into account for electronic components. Also, net present value of the secondary cost including operational and maintenance costs has been calculated. The problem is formulated as a biobjective mathematical programming model aiming to reach a tradeoff between system reliability and cost. Three metaheuristic algorithms are employed to solve the proposed model: Nondominated Sorting Genetic Algorithm (NSGA-II, Multiobjective Particle Swarm Optimization (MOPSO, and Multiobjective Firefly Algorithm (MOFA. Several test problems are solved using the mentioned algorithms to test efficiency and effectiveness of the solution approaches and obtained results are analyzed.

Reliability centered maintenance pilot system implementation 241-AP-tank farm primary ventilation system final report

International Nuclear Information System (INIS)

MOORE TL

2001-01-01

When the Hanford Site Tank Farms' mission was safe storage of radioactive waste in underground storage tanks, maintenance activities focused on time-based preventive maintenance. Tank Farms' new mission to deliver waste to a vitrification plant where the waste will be processed into a form suitable for permanent storage requires a more efficient and proactive approach to maintenance. Systems must be maintained to ensure that they are operational and available to support waste feed delivery on schedule with a minimum of unplanned outages. This report describes the Reliability Centered Maintenance (RCM) pilot system that was implemented in the 241-AP Tank Farm Primary Ventilation System under PI-ORP-009 of the contract between the U.S. Department of Energy, Office of River Protection and CH2M HILL Hanford Group Inc. (CHG). The RCM analytical techniques focus on monitoring the condition of operating systems to predict equipment failures so that maintenance activities can be completed in time to prevent or mitigate unplanned equipment outages. This approach allows maintenance activities to be managed with minimal impact on plant operations. The pilot demonstration provided an opportunity for CHG staff-training in RCM principles and tailoring of the RCM approach to the Hanford Tank Farms' unique needs. This report details the implementation of RCM on a pilot system in Tank Farms

Present status of the Nuclear Maintenance Training Center

International Nuclear Information System (INIS)

Kotani, Fumio

1995-01-01

The education and training to keep and improve the knowledge and skills of the maintenance personnel and to hand down the skills undoubtedly play important roles in safe operation and increased reliability to a nuclear power station. The Nuclear Maintenance Training Center (hereafter called the Center) provides a variety of education and training curriculums based on the levels and abilities of the trainees. The Center aims to enhance the personnel's maintenance technique by offering the curriculums on maintenance basic education for operators and supporting education and training for the personnel of contractors. The Center has two main features: first, it has the actual components or the equipment similar to the actual components which will enable the practical training; second, we regard the past troubles as valuable experiences and, therefore, focuses on the education to prevent recurrence of troubles by teaching the trainees the meaning and necessity of the training they take. For eleven years since the establishment of the Center, it has been utilized by the total number of about 60,000 people. As for the tasks in the future, the Center is expected to vitalize itself to give attractive education and training and become more actively involved in development of the maintenance personnel with the adequate knowledge and skills. (author)

Identification of tasks of maintenance centered in the reliability; Identificacion de tareas de mantenimiento centrado en la confiabilidad

Energy Technology Data Exchange (ETDEWEB)

Torres V, A.; Rivero O, J.J. [Dpto. Ingenieria Nuclear, Instituto Superior de Tecnologias y Ciencias Aplicadas, Ave. Salvador Allende y Luaces, Quinta de los Molinos, Plaza, Ciudad Habana (Cuba)]. e-mail: atorres@fctn.isctn.edu.cu

2004-07-01

The methodology of Reliability Centered Maintenance (RCM) it has become, after the discovery of their advantages, an objective of many industrial facilities to optimize their maintenance. However, diverse subjective factors affect the determination of the parameters (technical of predictive to apply and times among interventions) that characterize the tasks of RCM. A method to determine the monitoring tasks at condition and the times more recommended for to apply the monitoring by time and the search of faults, with focus in system. This methodology has been computerized inside the code MOSEG Win Ver 1.0. The same has been applied with success to the determination of tasks of RCM in industrial objectives. (Author)

Reliability-centered maintenance for ground-based large optical telescopes and radio antenna arrays

Science.gov (United States)

Marchiori, G.; Formentin, F.; Rampini, F.

2014-07-01

In the last years, EIE GROUP has been more and more involved in large optical telescopes and radio antennas array projects. In this frame, the paper describes a fundamental aspect of the Logistic Support Analysis (LSA) process, that is the application of the Reliability-Centered Maintenance (RCM) methodology for the generation of maintenance plans for ground-based large optical telescopes and radio antennas arrays. This helps maintenance engineers to make sure that the telescopes continue to work properly, doing what their users require them to do in their present operating conditions. The main objective of the RCM process is to establish the complete maintenance regime, with the safe minimum required maintenance, carried out without any risk to personnel, telescope and subsystems. At the same time, a correct application of the RCM allows to increase the cost effectiveness, telescope uptime and items availability, and to provide greater understanding of the level of risk that the organization is managing. At the same time, engineers shall make a great effort since the initial phase of the project to obtain a telescope requiring easy maintenance activities and simple replacement of the major assemblies, taking special care on the accesses design and items location, implementation and design of special lifting equipment and handling devices for the heavy items. This maintenance engineering framework is based on seven points, which lead to the main steps of the RCM program. The initial steps of the RCM process consist of: system selection and data collection (MTBF, MTTR, etc.), definition of system boundaries and operating context, telescope description with the use of functional block diagrams, and the running of a FMECA to address the dominant causes of equipment failure and to lay down the Critical Items List. In the second part of the process the RCM logic is applied, which helps to determine the appropriate maintenance tasks for each identified failure mode. Once

Perancangan Sistem Pemeliharaan Menggunakan Metode Reliability Centered Maintenance (RCM Pada Pulverizer (Studi Kasus: PLTU Paiton Unit 3

Directory of Open Access Journals (Sweden)

RATNA BHAKTI PUSPITA SARI

2017-03-01

Full Text Available PLTU Paiton Unit 3 merupakan perusahaan yang bergerak di bidang produksi listrik menggunakan bahan baku batubara yang terletak di Paiton, Probolinggo. Untuk mencapai target, proses produksi dilakukan 24 jam selama 1 tahun tanpa henti. Program pemeliharaan mesin sangat penting untuk kelancaran proses produksi. Dalam rangka mencapai target tersebut dituntut adanya kelancaran batubara dari silo hingga surface burner menggunakan pulverizer. Data dari Departemen Engineering menunjukkan bahwa beberapa subsistem pulverizer sering mengalami kerusakan yang dapat menimbulkan kegagalan pada sistem tersebut. Penelitian tugas akhir ini menggunakan metode Reliability Centered Maintenance (RCM untuk menurunkan tingkat breakdown mesin dan downtime produksi. Data historis kerusakan pulverizer dianalisa. Kemudian kegagalan dari suatu komponen yang dapat menyebabkan kegagalan fungsi dari sistem diidentifikasi menggunakan metode Failure Mode and Effect Analysis (FMEA. Selanjutnya menggunakan RCM Decision Worksheet untuk mengetahui bagian dari sistem yang gagal dan perlu dilakukan tindakan perbaikan dan pencegahan berdasarkan kegagalan yang ada agar kejadian yang sama tidak terulang dan menentukan kegiatan perancang perawatan yang tepat pada setiap komponen Berdasarkan analisis data secara Reliability Centered Maintenance (RCM terdapat 12 failure mode yang terjadi pada pulverizer. 3 failure mode dapat dicegah dengan scheduled restoration task, 8 failure mode dapat dicegah dengan scheduled discard task, dan 1 failure mode dapat dicegah dengan redesign. Analisis kuantitatif menggunakan distribusi kegagalan dengan perangkat lunak Weibull++6 didapatkan MTBF grinding roller 2880,66 jam, MTBF hydraulic pump 5075,06 jam, MTBF gearbox 5381,65 jam dan MTBF coal feeder 525,17 jam.

Reliability Centered Maintenance (RCM) Methodology and Application to the Shutdown Cooling System for APR-1400 Reactors

Energy Technology Data Exchange (ETDEWEB)

Faragalla, Mohamed M.; Emmanuel, Efenji; Alhammadi, Ibrahim; Awwal, Arigi M.; Lee, Yong Kwan [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

2016-10-15

Shutdown Cooling System (SCS) is a safety-related system that is used in conjunction with the Main Steam and Main or Auxiliary Feedwater Systems to reduce the temperature of the Reactor Coolant System (RCS) in post shutdown periods from the hot shutdown operating temperature to the refueling temperature. In this paper RCM methodology is applied to (SCS). RCM analysis is performed based on evaluation of Failure Modes Effects and Criticality Analysis (FME and CA) on the component, system and plant. The Logic Tree Analysis (LTA) is used to determine the optimum maintenance tasks. The main objectives of RCM is the safety, preserve the System function, the cost-effective maintenance of the plant components and increase the reliability and availability value. The RCM methodology is useful for improving the equipment reliability by strengthening the management of equipment condition, and leads to a significant decrease in the number of periodical maintenance, extended maintenance cycle, longer useful life of equipment, and decrease in overall maintenance cost. It also focuses on the safety of the system by assigning criticality index to the various components and further selecting maintenance activities based on the risk of failure involved. Therefore, it can be said that RCM introduces a maintenance plan designed for maximum safety in an economical manner and making the system more reliable. For the SCP, increasing the number of condition monitoring tasks will improve the availability of the SCP. It is recommended to reduce the number of periodic maintenance activities.

Reliability centred maintenance of nuclear power plant facilities

International Nuclear Information System (INIS)

Kovacs, Zoltan; Novakova, Helena; Hlavac, Pavol; Janicek, Frantisek

2011-01-01

A method for the optimization of preventive maintenance nuclear power plant equipment, i.e. reliability centred maintenance, is described. The method enables procedures and procedure schedules to be defined such as allow the maintenance cost to be minimized without compromising operational safety or reliability. Also, combinations of facilities which remain available and ensure reliable operation of the reactor unit during the maintenance of other pieces of equipment are identified. The condition-based maintenance concept is used in this process, thereby preventing unnecessary operator interventions into the equipment, which are often associated with human errors. Where probabilistic safety assessment is available, the most important structures, systems and components with the highest maintenance priority can be identified. (orig.)

78 FR 44475 - Protection System Maintenance Reliability Standard

Science.gov (United States)

2013-07-24

... that the performance or product has some reliability-related value, then the requirement will have...] Protection System Maintenance Reliability Standard AGENCY: Federal Energy Regulatory Commission, Energy... Commission proposes to approve a revised Reliability Standard, PRC-005- 2--Protection System Maintenance, to...

Reliability-based performance simulation for optimized pavement maintenance

International Nuclear Information System (INIS)

Chou, Jui-Sheng; Le, Thanh-Son

2011-01-01

Roadway pavement maintenance is essential for driver safety and highway infrastructure efficiency. However, regular preventive maintenance and rehabilitation (M and R) activities are extremely costly. Unfortunately, the funds available for the M and R of highway pavement are often given lower priority compared to other national development policies, therefore, available funds must be allocated wisely. Maintenance strategies are typically implemented by optimizing only the cost whilst the reliability of facility performance is neglected. This study proposes a novel algorithm using multi-objective particle swarm optimization (MOPSO) technique to evaluate the cost-reliability tradeoff in a flexible maintenance strategy based on non-dominant solutions. Moreover, a probabilistic model for regression parameters is employed to assess reliability-based performance. A numerical example of a highway pavement project is illustrated to demonstrate the efficacy of the proposed MOPSO algorithms. The analytical results show that the proposed approach can help decision makers to optimize roadway maintenance plans. - Highlights: →A novel algorithm using multi-objective particle swarm optimization technique. → Evaluation of the cost-reliability tradeoff in a flexible maintenance strategy. → A probabilistic model for regression parameters is employed to assess reliability-based performance. → The proposed approach can help decision makers to optimize roadway maintenance plans.

Reliability-based performance simulation for optimized pavement maintenance

Energy Technology Data Exchange (ETDEWEB)

Chou, Jui-Sheng, E-mail: jschou@mail.ntust.edu.tw [Department of Construction Engineering, National Taiwan University of Science and Technology (Taiwan Tech), 43 Sec. 4, Keelung Rd., Taipei 106, Taiwan (China); Le, Thanh-Son [Department of Construction Engineering, National Taiwan University of Science and Technology (Taiwan Tech), 43 Sec. 4, Keelung Rd., Taipei 106, Taiwan (China)

2011-10-15

Roadway pavement maintenance is essential for driver safety and highway infrastructure efficiency. However, regular preventive maintenance and rehabilitation (M and R) activities are extremely costly. Unfortunately, the funds available for the M and R of highway pavement are often given lower priority compared to other national development policies, therefore, available funds must be allocated wisely. Maintenance strategies are typically implemented by optimizing only the cost whilst the reliability of facility performance is neglected. This study proposes a novel algorithm using multi-objective particle swarm optimization (MOPSO) technique to evaluate the cost-reliability tradeoff in a flexible maintenance strategy based on non-dominant solutions. Moreover, a probabilistic model for regression parameters is employed to assess reliability-based performance. A numerical example of a highway pavement project is illustrated to demonstrate the efficacy of the proposed MOPSO algorithms. The analytical results show that the proposed approach can help decision makers to optimize roadway maintenance plans. - Highlights: > A novel algorithm using multi-objective particle swarm optimization technique. > Evaluation of the cost-reliability tradeoff in a flexible maintenance strategy. > A probabilistic model for regression parameters is employed to assess reliability-based performance. > The proposed approach can help decision makers to optimize roadway maintenance plans.

Reliability and Maintainability model (RAM) user and maintenance manual. Part 2

Science.gov (United States)

Ebeling, Charles E.

1995-01-01

This report documents the procedures for utilizing and maintaining the Reliability and Maintainability Model (RAM) developed by the University of Dayton for the NASA Langley Research Center (LaRC). The RAM model predicts reliability and maintainability (R&M) parameters for conceptual space vehicles using parametric relationships between vehicle design and performance characteristics and subsystem mean time between maintenance actions (MTBM) and manhours per maintenance action (MH/MA). These parametric relationships were developed using aircraft R&M data from over thirty different military aircraft of all types. This report describes the general methodology used within the model, the execution and computational sequence, the input screens and data, the output displays and reports, and study analyses and procedures. A source listing is provided.

Application of reliability-centered maintenance to boiling water reactor emergency core cooling systems fault-tree analysis

International Nuclear Information System (INIS)

Choi, Y.A.; Feltus, M.A.

1995-01-01

Reliability-centered maintenance (RCM) methods are applied to boiling water reactor plant-specific emergency core cooling system probabilistic risk assessment (PRA) fault trees. The RCM is a technique that is system function-based, for improving a preventive maintenance (PM) program, which is applied on a component basis. Many PM programs are based on time-directed maintenance tasks, while RCM methods focus on component condition-directed maintenance tasks. Stroke time test data for motor-operated valves (MOVs) are used to address three aspects concerning RCM: (a) to determine if MOV stroke time testing was useful as a condition-directed PM task; (b) to determine and compare the plant-specific MOV failure data from a broad RCM philosophy time period compared with a PM period and, also, compared with generic industry MOV failure data; and (c) to determine the effects and impact of the plant-specific MOV failure data on core damage frequency (CDF) and system unavailabilities for these emergency systems. The MOV stroke time test data from four emergency core cooling systems [i.e., high-pressure coolant injection (HPCI), reactor core isolation cooling (RCIC), low-pressure core spray (LPCS), and residual heat removal/low-pressure coolant injection (RHR/LPCI)] were gathered from Philadelphia Electric Company's Peach Bottom Atomic Power Station Units 2 and 3 between 1980 and 1992. The analyses showed that MOV stroke time testing was not a predictor for eminent failure and should be considered as a go/no-go test. The failure data from the broad RCM philosophy showed an improvement compared with the PM-period failure rates in the emergency core cooling system MOVs. Also, the plant-specific MOV failure rates for both maintenance philosophies were shown to be lower than the generic industry estimates

Integrated reliability condition monitoring and maintenance of equipment

CERN Document Server

Osarenren, John

2015-01-01

Consider a Viable and Cost-Effective Platform for the Industries of the Future (IOF) Benefit from improved safety, performance, and product deliveries to your customers. Achieve a higher rate of equipment availability, performance, product quality, and reliability. Integrated Reliability: Condition Monitoring and Maintenance of Equipment incorporates reliable engineering and mathematical modeling to help you move toward sustainable development in reliability condition monitoring and maintenance. This text introduces a cost-effective integrated reliability growth monitor, integrated reliability degradation monitor, technological inheritance coefficient sensors, and a maintenance tool that supplies real-time information for predicting and preventing potential failures of manufacturing processes and equipment. The author highlights five key elements that are essential to any improvement program: improving overall equipment and part effectiveness, quality, and reliability; improving process performance with maint...

Machine Maintenance Scheduling with Reliability Engineering Method and Maintenance Value Stream Mapping

Science.gov (United States)

Sembiring, N.; Nasution, A. H.

2018-02-01

Corrective maintenance i.e replacing or repairing the machine component after machine break down always done in a manufacturing company. It causes the production process must be stopped. Production time will decrease due to the maintenance team must replace or repair the damage machine component. This paper proposes a preventive maintenance’s schedule for a critical component of a critical machine of an crude palm oil and kernel company due to increase maintenance efficiency. The Reliability Engineering & Maintenance Value Stream Mapping is used as a method and a tool to analize the reliability of the component and reduce the wastage in any process by segregating value added and non value added activities.

Assessment of reliability and maintenance of motor operated valves at Finnish NPPS

International Nuclear Information System (INIS)

Laakso, K.; Haenninen, S.; Simola, K.

1994-01-01

This paper summarizes two studies on motor operated valve (MOV) failure and maintenance experiences in Finnish nuclear power plants. In the first study, described in section 2 of this paper, the failure reports of MOVs at Finnish BWR units from a nine years' time period were analyzed in a systematic way. The dominant failure mechanisms were identified and time-dependencies in failure occurrence were studied. This study initiated an experience based reliability centered maintenance (RCM) analysis of motor operated valve drives, which is summarized in chapter 3 of this paper. The RCM analysis resulted in the identification and proposal of the most suitable and effective maintenance tasks for consideration. 9 refs, 3 figs, 1 tab

Reliability study: maintenance facilities Portsmouth Gaseous Diffusion Plant

International Nuclear Information System (INIS)

Post, B.E.; Sikorski, P.A.; Fankell, R.; Johnson, O.; Ferryman, D.S.; Miller, R.L.; Gearhart, E.C.; Rafferty, M.J.

1981-08-01

A reliability study of the maintenance facilities at the Portsmouth Gaseous Diffusion Plant has been completed. The reliability study team analyzed test data and made visual inspections of each component contributing to the overall operation of the facilities. The impacts of facilities and equipment failures were given consideration with regard to personnel safety, protection of government property, health physics, and environmental control. This study revealed that the maintenance facilities are generally in good condition. After evaluating the physical condition and technology status of the major components, the study team made several basic recommendations. Implementation of the recommendations proposed in this report will help assure reliable maintenance of the plant through the year 2000

Equipment reliability process improvement and preventive maintenance optimization

International Nuclear Information System (INIS)

Darragi, M.; Georges, A.; Vaillancourt, R.; Komljenovic, D.; Croteau, M.

2004-01-01

The Gentilly-2 Nuclear Power Plant wants to optimize its preventive maintenance program through an Integrated Equipment Reliability Process. All equipment reliability related activities should be reviewed and optimized in a systematic approach especially for aging plants such as G2. This new approach has to be founded on best practices methods with the purpose of the rationalization of the preventive maintenance program and the performance monitoring of on-site systems, structures and components (SSC). A rational preventive maintenance strategy is based on optimized task scopes and frequencies depending on their applicability, critical effects on system safety and plant availability as well as cost-effectiveness. Preventive maintenance strategy efficiency is systematically monitored through degradation indicators. (author)

A reliability centered maintenance model applied to the auxiliary feedwater system of a nuclear power plant; Um modelo de manutencao centrada em confiabilidade aplicada ao sistema de agua de alimentacaco auxiliar de uma usina nuclear

Energy Technology Data Exchange (ETDEWEB)

Araujo, Jefferson Borges

1998-01-15

The main objective of maintenance in a nuclear power plant is to assure that structures, systems and components will perform their design functions with reliability and availability in order to obtain a safety and economic electric power generation. Reliability Centered Maintenance (RCM) is a method of systematic review to develop or optimize Preventive Maintenance Programs. This study presents the objectives, concepts, organization and methods used in the development of RCM application to nuclear power plants. Some examples of this application are included, considering the Auxiliary Feedwater System of a generic two loops PWR nuclear power plant of Westinghouse design. (author)

Reliability analysis of maintenance operations for railway tracks

International Nuclear Information System (INIS)

Rhayma, N.; Bressolette, Ph.; Breul, P.; Fogli, M.; Saussine, G.

2013-01-01

Railway engineering is confronted with problems due to degradation of the railway network that requires important and costly maintenance work. However, because of the lack of knowledge on the geometrical and mechanical parameters of the track, it is difficult to optimize the maintenance management. In this context, this paper presents a new methodology to analyze the behavior of railway tracks. It combines new diagnostic devices which permit to obtain an important amount of data and thus to make statistics on the geometric and mechanical parameters and a non-intrusive stochastic approach which can be coupled with any mechanical model. Numerical results show the possibilities of this methodology for reliability analysis of different maintenance operations. In the future this approach will give important informations to railway managers to optimize maintenance operations using a reliability analysis

Engineering systems reliability, safety, and maintenance an integrated approach

CERN Document Server

Dhillon, B S

2017-01-01

Today, engineering systems are an important element of the world economy and each year billions of dollars are spent to develop, manufacture, operate, and maintain various types of engineering systems around the globe. Many of these systems are highly sophisticated and contain millions of parts. For example, a Boeing jumbo 747 is made up of approximately 4.5 million parts including fasteners. Needless to say, reliability, safety, and maintenance of systems such as this have become more important than ever before.　 Global competition and other factors are forcing manufacturers to produce highly reliable, safe, and maintainable engineering products. Therefore, there is a definite need for the reliability, safety, and maintenance professionals to work closely during design and other phases. Engineering Systems Reliability, Safety, and Maintenance: An Integrated Approach eliminates the need to consult many different and diverse sources in the hunt for the information required to design better engineering syste...

Maintenance optimization plan for essential equipment reliability

International Nuclear Information System (INIS)

Steffen, D.H.

1996-02-01

The Maintenance Optimization Plan (MOP) for Essential Equipment Reliability will furnish Tank Waste Remediation System (TWRS) management with a pro-active, forward-thinking process for maintaining essential structures, systems, and components (ESSC) at the Hanford Site tank farms in their designed condition, and to ensure optimum ESSC availability and reliability

Perencanaan Kegiatan Maintenance Dengan Metode Reability Centered Maintenance (Rcm) II

OpenAIRE

Rachmad Hidayat; Nachnul Ansori; Ali Imron

2010-01-01

Maintenance Activity Planning by Reability Centered Maintenance (RCM) II Method. This research discussmaintenance activity by using RCM II method to determine failure function risk at compresor screw. Calculation isgiven to magnitude optimum time maintenance interval by considering the cost maintenance and the cost reparation.From the research results with RPN points out that critical component that needs to get main priority in givemaintenance on compresor screw are bust logistic on timeworn...

Reliability in maintenance and design of elastomer sealed closures

International Nuclear Information System (INIS)

Lake, W.H.

1978-01-01

The methods of reliability are considered for maintenance and design of elastomer sealed containment closures. Component reliability is used to establish a replacement schedule for system maintenance. Reliability data on elastomer seals is used to evaluate the common practice of annual replacement, and to calculate component reliability values for several typical shipment time periods. System reliability methods are used to examine the relative merits of typical closure designs. These include single component and redundant seal closure, with and without closure verification testing. The paper presents a general method of quantifying the merits of closure designs through the use of reliability analysis, which is a probabilistic technique. The reference list offers a general source of information in the field of reliability, and should offer the opportunity to extend the procedures discussed in this paper to other design safety applications

Reliability assessment of power pole infrastructure incorporating deterioration and network maintenance

International Nuclear Information System (INIS)

Ryan, Paraic C.; Stewart, Mark G.; Spencer, Nathan; Li, Yue

2014-01-01

There is considerable investment in timber utility poles worldwide, and there is a need to examine the structural reliability and probability based management optimisation of these power distribution infrastructure elements. The work presented in this paper builds on the existing studies in this area through assessment of both treated and untreated timber power poles, with the effects of deterioration and network maintenance incorporated in the analysis. This more realistic assessment approach, with deterioration and maintenance considered, was achieved using event-based Monte Carlo simulation. The output from the probabilistic model is used to illustrate the importance of considering network maintenance in the time-dependent structural reliability assessment of timber power poles. Under wind load, treated and untreated poles designed and maintained in accordance with existing Australian standards were found to have similar failure rates. However, untreated pole networks required approximately twice as many maintenance based pole replacements to sustain the same level of reliability. The effect of four different network maintenance strategies on infrastructure performance was also investigated herein. This assessment highlighted the fact that slight alterations to network maintenance practices can lead to significant changes in performance of timber power pole networks. - Highlights: • A time-dependent structural reliability model was developed for timber power poles. • Deterioration and network maintenance were incorporated into this event based model. • Network maintenance had a significant impact on power pole wind vulnerability. • Treated and untreated poles designed to Australian standards had similar reliability. • Minor alterations to maintenance strategies had large effects on network performance

On reliability and maintenance modelling of ageing equipment in electric power systems

International Nuclear Information System (INIS)

Lindquist, Tommie

2008-04-01

Maintenance optimisation is essential to achieve cost-efficiency, availability and reliability of supply in electric power systems. The process of maintenance optimisation requires information about the costs of preventive and corrective maintenance, as well as the costs of failures borne by both electricity suppliers and customers. To calculate expected costs, information is needed about equipment reliability characteristics and the way in which maintenance affects equipment reliability. The aim of this Ph.D. work has been to develop equipment reliability models taking the effect of maintenance into account. The research has focussed on the interrelated areas of condition estimation, reliability modelling and maintenance modelling, which have been investigated in a number of case studies. In the area of condition estimation two methods to quantitatively estimate the condition of disconnector contacts have been developed, which utilise results from infrared thermography inspections and contact resistance measurements. The accuracy of these methods were investigated in two case studies. Reliability models have been developed and implemented for SF6 circuit-breakers, disconnector contacts and XLPE cables in three separate case studies. These models were formulated using both empirical and physical modelling approaches. To improve confidence in such models a Bayesian statistical method incorporating information from the equipment design process was also developed. This method was illustrated in a case study of SF6 circuit-breaker operating rods. Methods for quantifying the effect of maintenance on equipment condition and reliability have been investigated in case studies on disconnector contacts and SF6 circuit-breakers. The input required by these methods are condition measurements and historical failure and maintenance data, respectively. This research has demonstrated that the effect of maintenance on power system equipment may be quantified using available data

Technical information report: Plasma melter operation, reliability, and maintenance analysis

International Nuclear Information System (INIS)

Hendrickson, D.W.

1995-01-01

This document provides a technical report of operability, reliability, and maintenance of a plasma melter for low-level waste vitrification, in support of the Hanford Tank Waste Remediation System (TWRS) Low-Level Waste (LLW) Vitrification Program. A process description is provided that minimizes maintenance and downtime and includes material and energy balances, equipment sizes and arrangement, startup/operation/maintence/shutdown cycle descriptions, and basis for scale-up to a 200 metric ton/day production facility. Operational requirements are provided including utilities, feeds, labor, and maintenance. Equipment reliability estimates and maintenance requirements are provided which includes a list of failure modes, responses, and consequences

System reliability as perceived by maintenance personnel on petroleum production facilities

International Nuclear Information System (INIS)

Antonovsky, A.; Pollock, C.; Straker, L.

2016-01-01

The aim of this research was to understand the relationship between maintenance staff perceptions of organisational effectiveness and operational reliability in petroleum operations. Engineering measures exist that assess the effectiveness of maintenance and reliability of equipment. These measures are typically retrospective and may not provide insight into what impedes system reliability. Perceptions of organisational effectiveness by the workforce may provide a predictive measure that could improve our understanding of the human factors that influence system reliability. Maintenance personnel (n=133) from nine petroleum production facilities completed a survey as part of a study of human factors and maintenance reliability. 69 respondents (51.9%) provided comments to an open-ended question in the survey, and these data were analysed using Interpretive Phenomenological Analysis to extract themes. Four super-ordinate themes were identified from the analysis: 1) Communication and access to information, 2) Efficiency of current work systems, 3) Need for better workgroup support, and 4) Management impacts on the workplace. We found a significant relationship between the frequency of the four super-ordinate themes and the facility reliability level as measured by ‘Mean Time Between Failures’: χ"2(6,N=158)=16.2, p=.013. These results demonstrated that operational effectiveness might be differentiated on the basis of survey-derived perceptions of maintenance personnel. - Highlights: • Thematic analysis of survey comments provided insights into workplace reliability • Worker’s comments on reliability related to technical data on time between failures • Management decision-making was the main theme in the lower reliability workplaces • Improving efficiency was the main theme in the higher reliability workplaces • Communication and better workgroup support were themes at all reliability levels

Study on the Management for the Nuclear Power Plant Maintenance and Equipment Reliability

International Nuclear Information System (INIS)

Yoon, Kyeongseop; Lee, Sangheon; Kim, Myungjin; Lee, Unjang

2015-01-01

In our country, many studies on the regulatory policy of the plant maintenance have ever been performed since 1998, but the relevant regulatory requirements were not established yet. These background mentioned above request us to study on the regulation policy and maintenance plan to improve the safety, reliability and efficiency of NPP. To solve these problems, in this study, we deduct the management methodology for the improvement of NPP maintenance and equipment reliability that is essential to secure the safety and efficiency of the commercial NPP. For analysis the maintenance and equipment reliability management methodology in overseas NPP. We studied maintenance and equipment reliability of USA, Canada and Europe(France, England, German). We also studied status and application condition of Korean NPP maintenance management technical development. We deducted an effective maintenance methodology that is needed to Korean NPP, as a result of comparison on the technical trend of the maintenance management between overseas and Korean, such like following. - Regulation form ·Specific provision of regulation requirement and application of form that is clarifying application standard - Maintenance management methodology, Maintenance management program. This results of study could be applied for regulation policy, law and guideline establishment of NPP maintenance, operation, supervision and a system establishment for maintenance management, education data about maintenance for NPP employees

Maintenance management of railway infrastructures based on reliability analysis

International Nuclear Information System (INIS)

Macchi, Marco; Garetti, Marco; Centrone, Domenico; Fumagalli, Luca; Piero Pavirani, Gian

2012-01-01

Railway infrastructure maintenance plays a crucial role for rail transport. It aims at guaranteeing safety of operations and availability of railway tracks and related equipment for traffic regulation. Moreover, it is one major cost for rail transport operations. Thus, the increased competition in traffic market is asking for maintenance improvement, aiming at the reduction of maintenance expenditures while keeping the safety of operations. This issue is addressed by the methodology presented in the paper. The first step of the methodology consists of a family-based approach for the equipment reliability analysis; its purpose is the identification of families of railway items which can be given the same reliability targets. The second step builds the reliability model of the railway system for identifying the most critical items, given a required service level for the transportation system. The two methods have been implemented and tested in practical case studies, in the context of Rete Ferroviaria Italiana, the Italian public limited company for railway transportation.

Application of reliability centred maintenance to optimize operation and maintenance in nuclear power plants

International Nuclear Information System (INIS)

2007-05-01

In order to increase Member States capabilities in utilizing good engineering and management practices the Agency has developed a series of Technical Documents (TECDOCs) to describe best practices and members experience in the application of them. This TECDOC describes the concept of Reliability Centred Maintenance (RCM) which is the term used to describe a systematic approach to the evaluation, design and development of cost effective maintenance programmes for plant and equipment. The concept has been in existence for over 25 years originating in the civil aviation sector. This TECDOC supplements previous IAEA publications on the subject and seeks to reflect members experience in the application of the principles involved. The process focuses on the functionality of the plant and equipment and the critical failure mechanisms that could result in the loss of functionality. When employed effectively the process can result in the elimination of unnecessary maintenance activities and the identification and introduction of measures to address deficiencies in the maintenance programme. Overall the process can result in higher levels of reliability for the plant and equipment at reduced cost and demands on finite maintenance resources. The application of the process requires interaction between the operators and the maintenance practitioners which is often lacking in traditional maintenance programmes. The imposition of this discipline produces the added benefit of improved information flows between the key players in plant and equipment management with the result that maintenance activities and operational practices are better informed. This publication was produced within IAEA programme on nuclear power plants operating performance and life cycle management

Design of preventive maintenance system using the reliability engineering and maintenance value stream mapping methods in PT. XYZ

Science.gov (United States)

Sembiring, N.; Panjaitan, N.; Angelita, S.

2018-02-01

PT. XYZ is a company owned by non-governmental organizations engaged in the field of production of rubber processing becoming crumb rubber. Part of the production is supported by some of machines and interacting equipment to achieve optimal productivity. Types of the machine that are used in the production process are Conveyor Breaker, Breaker, Rolling Pin, Hammer Mill, Mill Roll, Conveyor, Shredder Crumb, and Dryer. Maintenance system in PT. XYZ is corrective maintenance i.e. repairing or replacing the engine components after the crash on the machine. Replacement of engine components on corrective maintenance causes the machine to stop operating during the production process is in progress. The result is in the loss of production time due to the operator must replace the damaged engine components. The loss of production time can impact on the production targets which were not reached and lead to high loss costs. The cost for all components is Rp. 4.088.514.505. This cost is really high just for maintaining a Mill Roll Machine. Therefore PT. XYZ is needed to do preventive maintenance i.e. scheduling engine components and improving maintenance efficiency. The used methods are Reliability Engineering and Maintenance Value Stream Mapping (MVSM). The needed data in this research are the interval of time damage to engine components, opportunity cost, labor cost, component cost, corrective repair time, preventive repair time, Mean Time To Opportunity (MTTO), Mean Time To Repair (MTTR), and Mean Time To Yield (MTTY). In this research, the critical components of Mill Roll machine are Spier, Bushing, Bearing, Coupling and Roll. Determination of damage distribution, reliability, MTTF, cost of failure, cost of preventive, current state map, and future state map are done so that the replacement time for each critical component with the lowest maintenance cost and preparation of Standard Operation Procedure (SOP) are developed. For the critical component that has been

Imperfect Preventive Maintenance Model Study Based On Reliability Limitation

Directory of Open Access Journals (Sweden)

Zhou Qian

2016-01-01

Full Text Available Effective maintenance is crucial for equipment performance in industry. Imperfect maintenance conform to actual failure process. Taking the dynamic preventive maintenance cost into account, the preventive maintenance model was constructed by using age reduction factor. The model regards the minimization of repair cost rate as final target. It use allowed smallest reliability as the replacement condition. Equipment life was assumed to follow two parameters Weibull distribution since it was one of the most commonly adopted distributions to fit cumulative failure problems. Eventually the example verifies the rationality and benefits of the model.

A reliability-based preventive maintenance methodology for the projection spot welding machine

Directory of Open Access Journals (Sweden)

Fayzimatov Ulugbek

2018-06-01

Full Text Available An effective operations of a projection spot welding (PSW machine is closely related to the effec-tiveness of the maintenance. Timely maintenance can prevent failures and improve reliability and maintainability of the machine. Therefore, establishing the maintenance frequency for the welding machine is one of the most important tasks for plant engineers. In this regard, reliability analysis of the welding machine can be used to establish preventive maintenance intervals (PMI and to identify the critical parts of the system. In this reliability and maintainability study, analysis of the PSW machine was carried out. The failure and repair data for analysis were obtained from automobile manufacturing company located in Uzbekistan. The machine was divided into three main sub-systems: electrical, pneumatic and hydraulic. Different distributions functions for all sub-systems was tested and their parameters tabulated. Based on estimated parameters of the analyzed distribu-tions, PMI for the PSW machines sub-systems at different reliability levels was calculated. Finally, preventive measures for enhancing the reliability of the PSW machine sub-systems are suggested.

Maintenance overtime policies in reliability theory models with random working cycles

CERN Document Server

Nakagawa, Toshio

2015-01-01

This book introduces a new concept of replacement in maintenance and reliability theory. Replacement overtime, where replacement occurs at the first completion of a working cycle over a planned time, is a new research topic in maintenance theory and also serves to provide a fresh optimization technique in reliability engineering. In comparing replacement overtime with standard and random replacement techniques theoretically and numerically, 'Maintenance Overtime Policies in Reliability Theory' highlights the key benefits to be gained by adopting this new approach and shows how they can be applied to inspection policies, parallel systems and cumulative damage models. Utilizing the latest research in replacement overtime by internationally recognized experts, readers are introduced to new topics and methods, and learn how to practically apply this knowledge to actual reliability models. This book will serve as an essential guide to a new subject of study for graduate students and researchers and also provides a...

Failure and Maintenance Analysis Using Web-Based Reliability Database System

International Nuclear Information System (INIS)

Hwang, Seok Won; Kim, Myoung Su; Seong, Ki Yeoul; Na, Jang Hwan; Jerng, Dong Wook

2007-01-01

Korea Hydro and Nuclear Power Company has lunched the development of a database system for PSA and Maintenance Rule implementation. It focuses on the easy processing of raw data into a credible and useful database for the risk-informed environment of nuclear power plant operation and maintenance. Even though KHNP had recently completed the PSA for all domestic NPPs as a requirement of the severe accident mitigation strategy, the component failure data were only gathered as a means of quantification purposes for the relevant project. So, the data were not efficient enough for the Living PSA or other generic purposes. Another reason to build a real time database is for the newly adopted Maintenance Rule, which requests the utility to continuously monitor the plant risk based on its operation and maintenance performance. Furthermore, as one of the pre-condition for the Risk Informed Regulation and Application, the nuclear regulatory agency of Korea requests the development and management of domestic database system. KHNP is stacking up data of operation and maintenance on the Enterprise Resource Planning (ERP) system since its first opening on July, 2003. But, so far a systematic review has not been performed to apply the component failure and maintenance history for PSA and other reliability analysis. The data stored in PUMAS before the ERP system is introduced also need to be converted and managed into the new database structure and methodology. This reliability database system is a web-based interface on a UNIX server with Oracle relational database. It is designed to be applicable for all domestic NPPs with a common database structure and the web interfaces, therefore additional program development would not be necessary for data acquisition and processing in the near future. Categorization standards for systems and components have been implemented to analyze all domestic NPPs. For example, SysCode (for a system code) and CpCode (for a component code) were newly

Dynamic decision-making for reliability and maintenance analysis of manufacturing systems based on failure effects

Science.gov (United States)

Zhang, Ding; Zhang, Yingjie

2017-09-01

A framework for reliability and maintenance analysis of job shop manufacturing systems is proposed in this paper. An efficient preventive maintenance (PM) policy in terms of failure effects analysis (FEA) is proposed. Subsequently, reliability evaluation and component importance measure based on FEA are performed under the PM policy. A job shop manufacturing system is applied to validate the reliability evaluation and dynamic maintenance policy. Obtained results are compared with existed methods and the effectiveness is validated. Some vague understandings for issues such as network modelling, vulnerabilities identification, the evaluation criteria of repairable systems, as well as PM policy during manufacturing system reliability analysis are elaborated. This framework can help for reliability optimisation and rational maintenance resources allocation of job shop manufacturing systems.

Reliability theory with applications to preventive maintenance

CERN Document Server

Gertsbakh, Ilya

2000-01-01

The material in this book was first presented as a one-semester course in Relia­ bility Theory and Preventive Maintenance for M.Sc. students of the Industrial Engineering Department of Ben Gurion University in the 1997/98 and 1998/99 academic years. Engineering students are mainly interested in the applied part of this theory. The value of preventive maintenance theory lies in the possibility of its imple­ mentation, which crucially depends on how we handle statistical reliability data. The very nature of the object of reliability theory - system lifetime - makes it extremely difficult to collect large amounts of data. The data available are usu­ ally incomplete, e.g. heavily censored. Thus, the desire to make the course material more applicable led me to include in the course topics such as mod­ eling system lifetime distributions (Chaps. 1,2) and the maximum likelihood techniques for lifetime data processing (Chap. 3). A course in the theory of statistics is aprerequisite for these lectures. Stan­ dard...

Stochastic reliability and maintenance modeling essays in honor of Professor Shunji Osaki on his 70th birthday

CERN Document Server

Nakagawa, Toshio

2013-01-01

In honor of the work of Professor Shunji Osaki, Stochastic Reliability and Maintenance Modeling provides a comprehensive study of the legacy of and ongoing research in stochastic reliability and maintenance modeling. Including associated application areas such as dependable computing, performance evaluation, software engineering, communication engineering, distinguished researchers review and build on the contributions over the last four decades by Professor Shunji Osaki. Fundamental yet significant research results are presented and discussed clearly alongside new ideas and topics on stochastic reliability and maintenance modeling to inspire future research. Across 15 chapters readers gain the knowledge and understanding to apply reliability and maintenance theory to computer and communication systems. Stochastic Reliability and Maintenance Modeling is ideal for graduate students and researchers in reliability engineering, and workers, managers and engineers engaged in computer, maintenance and management wo...

Degradation mode analysis: An approach to establish effective predictive maintenance tasks

International Nuclear Information System (INIS)

Sonnett, D.E.; Douglass, P.T.; Barnard, D.D.

1991-01-01

A significant number of nuclear generating stations have been employing Reliability Centered Maintenance methodology to arrive at applicable and effective maintenance tasks for their plant equipment. The resultant endpoint of most programs has been an increased emphasis on predictive maintenance as the task of choice for monitoring and trending plant equipment condition to address failure mechanisms of the analyses. Many of these plants have spent several years conducting reliability centered analysis before they seriously begin implementing predictive program improvements. In this paper we present another methodology, entitled Degradation Mode Analysis, which provides a more direct method to quickly and economically achieve the major benefit of reliability centered analysis, namely predictive maintenance. (author)

Stochastic models in reliability and maintenance

CERN Document Server

2002-01-01

Our daily lives can be maintained by the high-technology systems. Computer systems are typical examples of such systems. We can enjoy our modern lives by using many computer systems. Much more importantly, we have to maintain such systems without failure, but cannot predict when such systems will fail and how to fix such systems without delay. A stochastic process is a set of outcomes of a random experiment indexed by time, and is one of the key tools needed to analyze the future behavior quantitatively. Reliability and maintainability technologies are of great interest and importance to the maintenance of such systems. Many mathematical models have been and will be proposed to describe reliability and maintainability systems by using the stochastic processes. The theme of this book is "Stochastic Models in Reliability and Main­ tainability. " This book consists of 12 chapters on the theme above from the different viewpoints of stochastic modeling. Chapter 1 is devoted to "Renewal Processes," under which cla...

Age-dependent reliability model considering effects of maintenance and working conditions

International Nuclear Information System (INIS)

Martorell, Sebastian; Sanchez, Ana; Serradell, Vicente

1999-01-01

Nowadays, there is some doubt about building new nuclear power plants (NPPs). Instead, there is a growing interest in analyzing the possibility to extend current NPP operation, where life management programs play an important role. The evolution of the NPP safety depends on the evolution of the reliability of its safety components, which, in turn, is a function of their age along the NPP operational life. In this paper, a new age-dependent reliability model is presented, which includes parameters related to surveillance and maintenance effectiveness and working conditions of the equipment, both environmental and operational. This model may be used to support NPP life management and life extension programs, by improving or optimizing surveillance and maintenance tasks using risk and cost models based on such an age-dependent reliability model. The results of the sensitivity study in the example application show that the selection of the most appropriate maintenance strategy would directly depend on the previous parameters. Then, very important differences are expected to appear under certain circumstances, particularly, in comparison with other models that do not consider maintenance effectiveness and working conditions simultaneously

Optimizing preventive maintenance with maintenance templates

International Nuclear Information System (INIS)

Dozier, I.J.

1996-01-01

Rising operating costs has caused maintenance professionals to rethink their strategy for preventive maintenance (PM) programs. Maintenance Templates are pre-engineered PM task recommendations for a component type based on application of the component. Development of the maintenance template considers the dominant failure cause of the component and the type of preventive maintenance that can predict or prevent the failure from occurring. Maintenance template development also attempts to replace fixed frequency tasks with condition monitoring tasks such as vibration analysis or thermography. For those components that have fixed frequency PM intervals, consideration is given to the maintenance drivers such as criticality, environment and usage. This helps to maximize the PM frequency intervals and maximize the component availability. Maintenance Templates have been used at PECO Energy's Limerick Generating Station during the Reliability Centered Maintenance (RCM) Process to optimize their PM program. This paper describes the development and uses of the maintenance templates

North American nuclear maintenance best practices compared to Japanese utility maintenance practices

International Nuclear Information System (INIS)

Harazim, M.L.; Ferguson, B.J.

2003-01-01

The purpose of this paper is to compare the best practices in North America concerning Preventive Maintenance, Predictive Maintenance and Reliability Centered Maintenance (RCM) or Preventive Maintenance Optimization (PMO) with the time-directed maintenance philosophies utilized by Japanese utilities, and how the Japanese utilities are considering (and some have begun) adopting North American ways of doing business. Preventive Maintenance Living Programs are also discussed, along with the Institute of Nuclear Power Operations AP-913 process, Equipment Reliability Process. Also, a cost benefit analysis will be demonstrated showing how major cost savings can be achieved by shifting from a predominantly time-directed maintenance philosophy to a predominantly predictive strategy utilizing vibration analysis, lubricating oil analysis, thermography and other predictive technologies to better utilize resources, reduce spare part consumption and to minimize maintenance induced errors. As a result of the strides made while incorporating these new philosophies, we no longer advocate tearing apart perfectly good equipment. (author)

Developing Predictive Maintenance Expertise to Improve Plant Equipment Reliability

International Nuclear Information System (INIS)

Wurzbach, Richard N.

2002-01-01

On-line equipment condition monitoring is a critical component of the world-class production and safety histories of many successful nuclear plant operators. From addressing availability and operability concerns of nuclear safety-related equipment to increasing profitability through support system reliability and reduced maintenance costs, Predictive Maintenance programs have increasingly become a vital contribution to the maintenance and operation decisions of nuclear facilities. In recent years, significant advancements have been made in the quality and portability of many of the instruments being used, and software improvements have been made as well. However, the single most influential component of the success of these programs is the impact of a trained and experienced team of personnel putting this technology to work. Changes in the nature of the power generation industry brought on by competition, mergers, and acquisitions, has taken the historically stable personnel environment of power generation and created a very dynamic situation. As a result, many facilities have seen a significant turnover in personnel in key positions, including predictive maintenance personnel. It has become the challenge for many nuclear operators to maintain the consistent contribution of quality data and information from predictive maintenance that has become important in the overall equipment decision process. These challenges can be met through the implementation of quality training to predictive maintenance personnel and regular updating and re-certification of key technology holders. The use of data management tools and services aid in the sharing of information across sites within an operating company, and with experts who can contribute value-added data management and analysis. The overall effectiveness of predictive maintenance programs can be improved through the incorporation of newly developed comprehensive technology training courses. These courses address the use of

From reliability to maintenance of emergency generator sets in nuclear plants

International Nuclear Information System (INIS)

Reyraud, Y.

1986-01-01

The particular conditions of operation of emergency generator sets in a nuclear energy plant induce to take up a strategy of supervision and of maintenance very different of the one recommended for production generator sets. Mechanical and thermal pulls are affected by the size of the set and the choice of rotation running in respect of the wanted power and the response time requirements for the security of nuclear reactor. Reliability studies are helpful to define the strategy of supervision tests. The importance of the number of starts with respect to the running time requires the introduction of the idea of equivalent hours for the definition of maintenance periods. The security of the equipment and the upholding of the reliability at a value close to the optimum impose rigorous choices and strict conditions of supervision and maintenance [fr

A study on maintenance reliability allocation of urban transit brake system using hybrid neuro-genetic technique

International Nuclear Information System (INIS)

Bae, Chul Ho; Kim, Hyun Jun; Lee, Jung Hwan; Suh, Myung Won; Chu, Yul

2007-01-01

For reasonable establishing of maintenance strategies, safety security and cost limitation must be considered at the same time. In this paper, the concept of system reliability introduces and optimizes as the key of reasonable maintenance strategies. This study aims at optimizing component's reliability that satisfies the target reliability of brake system in the urban transit. First of all, constructed reliability evaluation system is used to predict and analyze reliability. This data is used for the optimization. To identify component reliability in a system, a method is presented in this paper which uses hybrid neuro-genetic technique. Feed-forward multi-layer neural networks trained by back propagation are used to find out the relationship between component reliability (input) and system reliability (output) of a structural system. The inverse problem can be formulated by using neural network. Genetic algorithm is used to find the minimum square error. Finally, this paper presents reasonable maintenance cycle of urban transit brake system by using optimal system reliability

Initiating statistical maintenance optimization

International Nuclear Information System (INIS)

Doyle, E. Kevin; Tuomi, Vesa; Rowley, Ian

2007-01-01

Since the 1980 s maintenance optimization has been centered around various formulations of Reliability Centered Maintenance (RCM). Several such optimization techniques have been implemented at the Bruce Nuclear Station. Further cost refinement of the Station preventive maintenance strategy includes evaluation of statistical optimization techniques. A review of successful pilot efforts in this direction is provided as well as initial work with graphical analysis. The present situation reguarding data sourcing, the principle impediment to use of stochastic methods in previous years, is discussed. The use of Crowe/AMSAA (Army Materials Systems Analysis Activity) plots is demonstrated from the point of view of justifying expenditures in optimization efforts. (author)

Sensor/signal monitoring and plant maintenance

International Nuclear Information System (INIS)

Ciftcioglu, Oe.; Tuerkcan, E.

1994-02-01

Nuclear Power Plant (NPO) availability is determined by the intended functionality of safety related system and components. Therefore, maintenance is an important issue in a power plant connected to the plant's reliability and safety. The traditional maintenance policies proved to be rather costly and even not effectively addressing NPP requirements. Referring to these drawbacks, in the last decade, in the nuclear reliability centered maintenance (RCM) gained substantial interest due to its merits. In the formal implementation of RCM, apparently, predictive maintenance is not considered. However, with the impact of modern real-time and on-line surveillance and monitoring methodologies, the predictive maintenance procedures like sensor/signal verification and validation are to be included into RCM. (orig.)

Reliability and Maintainability Model (RAM): User and Maintenance Manual. Part 2; Improved Supportability Analysis

Science.gov (United States)

Ebeling, Charles E.

1996-01-01

This report documents the procedures for utilizing and maintaining the Reliability & Maintainability Model (RAM) developed by the University of Dayton for the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC). The purpose of the grant is to provide support to NASA in establishing operational and support parameters and costs of proposed space systems. As part of this research objective, the model described here was developed. This Manual updates and supersedes the 1995 RAM User and Maintenance Manual. Changes and enhancements from the 1995 version of the model are primarily a result of the addition of more recent aircraft and shuttle R&M data.

Exact reliability quantification of highly reliable systems with maintenance

Energy Technology Data Exchange (ETDEWEB)

Bris, Radim, E-mail: radim.bris@vsb.c [VSB-Technical University Ostrava, Faculty of Electrical Engineering and Computer Science, Department of Applied Mathematics, 17. listopadu 15, 70833 Ostrava-Poruba (Czech Republic)

2010-12-15

When a system is composed of highly reliable elements, exact reliability quantification may be problematic, because computer accuracy is limited. Inaccuracy can be due to different aspects. For example, an error may be made when subtracting two numbers that are very close to each other, or at the process of summation of many very different numbers, etc. The basic objective of this paper is to find a procedure, which eliminates errors made by PC when calculations close to an error limit are executed. Highly reliable system is represented by the use of directed acyclic graph which is composed from terminal nodes, i.e. highly reliable input elements, internal nodes representing subsystems and edges that bind all of these nodes. Three admissible unavailability models of terminal nodes are introduced, including both corrective and preventive maintenance. The algorithm for exact unavailability calculation of terminal nodes is based on merits of a high-performance language for technical computing MATLAB. System unavailability quantification procedure applied to a graph structure, which considers both independent and dependent (i.e. repeatedly occurring) terminal nodes is based on combinatorial principle. This principle requires summation of a lot of very different non-negative numbers, which may be a source of an inaccuracy. That is why another algorithm for exact summation of such numbers is designed in the paper. The summation procedure uses benefits from a special number system with the base represented by the value 2{sup 32}. Computational efficiency of the new computing methodology is compared with advanced simulation software. Various calculations on systems from references are performed to emphasize merits of the methodology.

Efficiency evaluation of an electronic equipment: availability,reliability and maintenance

International Nuclear Information System (INIS)

Guyot, C.

1966-01-01

This concept of efficiency often called ''system effectiveness'', is presented and analyzed in terms of reliability and maintenance. It allows to define the availability factor of an electronic equipment. A procedure of evaluation is proposed. (A.L.B.)

Technology success: Integration of power plant reliability and effective maintenance

International Nuclear Information System (INIS)

Ferguson, K.

2008-01-01

The nuclear power generation sector has a tradition of utilizing technology as a key attribute for advancement. Companies that own, manage, and operate nuclear power plants can be expected to continue to rely on technology as a vital element of success. Inherent with the operations of the nuclear power industry in many parts of the world is the close connection between efficiency of power plant operations and successful business survival. The relationship among power plant availability, reliability of systems and components, and viability of the enterprise is more evident than ever. Technology decisions need to be accomplished that reflect business strategies, work processes, as well as needs of stakeholders and authorities. Such rigor is needed to address overarching concerns such as power plant life extension and license renewal, new plant orders, outage management, plant safety, inventory management etc. Particular to power plant reliability, the prudent leveraging of technology as a key to future success is vital. A dominant concern is effective asset management as physical plant assets age. Many plants are in, or are entering in, a situation in which systems and component design life and margins are converging such that failure threats can come into play with increasing frequency. Wisely selected technologies can be vital to the identification of emerging threats to reliable performance of key plant features and initiating effective maintenance actions and investments that can sustain or enhance current reliability in a cost effective manner. This attention to detail is vital to investment in new plants as well This paper and presentation will address (1) specific technology success in place at power plants, including nuclear, that integrates attention to attaining high plant reliability and effective maintenance actions as well as (2) complimentary actions that maximize technology success. In addition, the range of benefits that accrue as a result of

A Study on the Joint Reliability Importance with Applications to the Maintenance Policy

Energy Technology Data Exchange (ETDEWEB)

Hong, Jung Sik; Kwon, Hong Je; Song, Mi Ja; Kim, Woong Kil; Yoong, Do Hwa [Seoul National Polytechnic University, Seoul (Korea, Republic of); Moon, Sin Myung; Cho, Bong Je; Moon, Jae Phil; Koo, Hoon Young; Lee, Jin Seung [Seoul National University, Seoul (Korea, Republic of)

1997-09-01

The objective of this project is to investigate the possibility of applying the Joint Reliability Importance(JRI) of two components to the establishment of system maintenance policy. Components are classified into reliability substitutes and reliability compliments. If the sign of JRI of two components is positive, they are called as reliability compliments. If the sign of JRI of two components is negative, they are called as reliability substitutes. In case of reliability compliments, one component becomes more important as the other one works and in case of reliability substitutes, one component becomes more important as the other one fails. Therefore, when the preventive maintenance is carried out, two components which are reliability substitutes should not be maintained at the same time. Also, when the corrective maintenance is carried out, we not only repair the failed components but pay attention to the functioning components which are reliability substitutes with respect to the failed components. The sign of JRI of any two components in series (parallel) system is positive (negative). Then, what is the sign of any two components in k-out-of-n:G system? This project presents an idea of characterizing the k-out-of-n:G system by calculating the JRI of two components in that system, assuming that reliability of all components are equal. In addition to the JRI of two components, JRI of two gates is introduced in this project. The algorithm to compute the JRI of two gates is presented. Bridge system is considered and the co-relation of two min cut sets is illustrated by using the cut-set representation of bridge system and calculating the JRI of two gates. 28 refs., 20 tabs., 32 figs. (author)

49 CFR Appendix E to Part 238 - General Principles of Reliability-Based Maintenance Programs

Science.gov (United States)

2010-10-01

... STANDARDS Pt. 238, App. E Appendix E to Part 238—General Principles of Reliability-Based Maintenance... 49 Transportation 4 2010-10-01 2010-10-01 false General Principles of Reliability-Based... the design level of safety and reliability of the equipment; (2) To restore safety and reliability to...

Reliability-Centered Maintenance

Science.gov (United States)

1978-12-29

and Eisenhart et al. (1947) summarized other statistical developments derived at Columbia. The second period of development, which had its roots in...January 1970 (FFA 120). Eisenhart , C., M. W. I-lastay, and W. A. Wallis (1947) Techniques of Statistical Analysis. McGraw-Hill Book Company, Inc., New...Miller, Douglas R. (1976) Abnost Sure Comiparisons ol Renewal Processes and Poisso:i Processes u’to *; Application to Reliabilityj Theo ; t, University of

Fuzzy Goal Programming Approach in Selective Maintenance Reliability Model

Directory of Open Access Journals (Sweden)

Neha Gupta

2013-12-01

Full Text Available 800x600 In the present paper, we have considered the allocation problem of repairable components for a parallel-series system as a multi-objective optimization problem and have discussed two different models. In first model the reliability of subsystems are considered as different objectives. In second model the cost and time spent on repairing the components are considered as two different objectives. These two models is formulated as multi-objective Nonlinear Programming Problem (MONLPP and a Fuzzy goal programming method is used to work out the compromise allocation in multi-objective selective maintenance reliability model in which we define the membership functions of each objective function and then transform membership functions into equivalent linear membership functions by first order Taylor series and finally by forming a fuzzy goal programming model obtain a desired compromise allocation of maintenance components. A numerical example is also worked out to illustrate the computational details of the method.  Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

On maintenance management of wind and nuclear power plants

International Nuclear Information System (INIS)

Nilsson, Julia

2009-11-01

Electrical production in Sweden today is mainly from nuclear and hydro power. However, there is large increase in renewable energy like wind power and the installed new capacity goals are large. Several electrical production sources are important for the sustainability of the energy system. Maintenance is an approach for keeping a system sustainable. The importance of structured maintenance for reliable electrical production systems triggers the development of qualitative and quantitative maintenance management methods. Examples of these methods are Reliability-Centered Maintenance (RCM) which is a structured qualitative approach that focuses on reliability when planning maintenance, and Reliability Centered Asset Management (RCAM) which is a development of RCM into a quantitative approach with the aim to relate preventive maintenance to total maintenance cost and system reliability. This thesis presents models, as applications of RCAM, based on the methods of Life Cycle Cost (LCC) and mathematical optimization, applied to wind and nuclear power plants. Both deterministic and stochastic approaches have been used and the proposed models are based on the Total Cost model, which summarizes costs for maintenance and production loss, and the Aircraft model, which is an opportunistic maintenance optimization model. Opportunistic maintenance is preventive maintenance performed at opportunities. The wind power applications in this study show on different ways to cover costs of condition monitoring systems (CMS) and further on economic benefits of these when uncertainties of times to failure are included in the model. The nuclear power applications show on that the optimization model is dependent on the discount rate and that a high discount rate gives more motivation for opportunistic replacements. When put into a stochastic framework and compared to other maintenance strategies it is shown that an extended opportunistic maintenance optimization model has a good overall

Planning of operation & maintenance using risk and reliability based methods

DEFF Research Database (Denmark)

Florian, Mihai; Sørensen, John Dalsgaard

2015-01-01

Operation and maintenance (OM) of offshore wind turbines contributes with a substantial part of the total levelized cost of energy (LCOE). The objective of this paper is to present an application of risk- and reliability-based methods for planning of OM. The theoretical basis is presented...

Mobile equipment maintenance at Elk Valley Coal Corporation Fording River

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-07-01

Major loading and support equipment, haul trucks, and the number of staff and hourly tradesmen working in the maintenance manpower division at Elk Valley Coal are listed. Maintenance strategies are safety, high maintenance of equipment availabilities and reliability, cost reduction, and maximized productivity of assets. Maintenance assets comprise a large shop, shovel and drill crew, machine shop, light vehicle facility, line crew, radio technicians, and cranes. Most maintenance work is completed in- house. Fording River uses a Computerized Maintenance Management System (CMMS) that was developed in-house to match business needs. Several examples of the application of Reliability Centered Maintenance (RCM) are described. 12 figs., 2 tabs.

Managing wind turbine reliability and maintenance via performance-based contract

DEFF Research Database (Denmark)

Jin, Tongdan; Ding, Yi; Guo, Huairui

2012-01-01

between system cost, reliability and spare parts stocking. This analytical insight into the system performance allows the turbine manufacturer to optimize design, production, and after-sales services. The study aims to create a theoretical basis to facilitate the transition of the maintenance paradigm......Performance-based contracting (PBC) is reshaping the acquisition, operation, and maintenance of capital equipment. Under the PBC scheme, we propose a holistic approach for lowering the cost of wind turbine ownership while meeting the availability requirement. Our effects are focused on integrated...... firms who design and market wind turbines, and also provide maintenance and repair service. PBC differs from conventional service contracts in that the wind farmers compensate the service provider for the system performance, not the spare parts and repair labor. We explore the analytical relationship...

A reliability-based maintenance technicians' workloads optimisation model with stochastic consideration

Science.gov (United States)

Ighravwe, D. E.; Oke, S. A.; Adebiyi, K. A.

2016-06-01

The growing interest in technicians' workloads research is probably associated with the recent surge in competition. This was prompted by unprecedented technological development that triggers changes in customer tastes and preferences for industrial goods. In a quest for business improvement, this worldwide intense competition in industries has stimulated theories and practical frameworks that seek to optimise performance in workplaces. In line with this drive, the present paper proposes an optimisation model which considers technicians' reliability that complements factory information obtained. The information used emerged from technicians' productivity and earned-values using the concept of multi-objective modelling approach. Since technicians are expected to carry out routine and stochastic maintenance work, we consider these workloads as constraints. The influence of training, fatigue and experiential knowledge of technicians on workload management was considered. These workloads were combined with maintenance policy in optimising reliability, productivity and earned-values using the goal programming approach. Practical datasets were utilised in studying the applicability of the proposed model in practice. It was observed that our model was able to generate information that practicing maintenance engineers can apply in making more informed decisions on technicians' management.

Improvement of the preventive maintenance program of an emergency diesel generator set

International Nuclear Information System (INIS)

Jacquot, J.P.; Meuwisse, C.; Cailleaux, J.P.

1995-01-01

An exhaustive Reliability Centered Maintenance (RCM) analysis was performed of the emergency diesel generator sets in Electricite de France 900-MW nuclear power plants. The first part of this paper describes the Reliability Centered Maintenance approach, including the functional breakdown, complete analysis of operation feedback and safety assessment of the risk induced by functional diesel failures. The second part shows how this kind of RCM analysis can be used to improve the efficiency of periodic tests of the machine, and more generally, the efficiency of condition-directed maintenance tasks. The underlying objective is to minimize risk and aging of the machine

Maintenance planning for nuclear power plants

International Nuclear Information System (INIS)

Mattu, R.K.; Cooper, S.E.; Lauderdale, J.R.

2004-01-01

Maintenance planning for nuclear power plants is similar to that in other industrial plants but it is heavily influenced by regulatory rules, with consequent costs of compliance. Steps by the nuclear industry and the Nuclear Regulatory Commission to address that problem include development of guidelines for maintenance of risk-critical equipment, using PRA-based techniques to select a set of equipment that requires maintenance and reliability-centered maintenance (RCM) approaches for determining what maintenance is required. The result of the process is a program designed to ensure effective maintenance of the equipment most critical to plant safety. (author)

Reliability and Maintenance for Offshore Wind Turbines and Wave Energy Devices

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard

2015-01-01

Wind turbines are in some countries contributing significantly the production of electricity and wave energy devices have the potential to be developed in a similarway. For both offshore wind turbines and wave energy devices reliability is a key issue since costs to operation and maintenance may...... be significant contributors to the Levelized Cost Of Energy and OM costs are highly dependent on the reliability of the components implying that it is important to focus on increasing the reliability as much as is economically reasonable. This paper describes basic aspects for reliability analysis of wind...... turbines and wave energy devices with special focus on structural components. The reliability assessment needs include the effects of the control system and possible faults due to failure of electrical/mechanical components and e.g. loss of grid connection. The target reliability level for wind turbine...

After reliability centred maintenance. Preventive maintenance living program implementation at Bruce Power

International Nuclear Information System (INIS)

Harazim, Michael L.; Ferguson, Brian J.

2003-01-01

Industrial preventive maintenance (PM) programs represent a large part of plant O and M costs. PM Optimization (PMO) projects represent an effective mechanism for identifying unnecessary PM, extending PM intervals and infusing predictive maintenance (PdM) methods. However, once optimized, what process prevents the PM program from returning to a state of disarray? This is the function of a PM living program (PMLP). In 1997, an independent performance assessment identified concerns with the applicability and effectiveness of all Ontario Power Generation, Inc. (OPGI) PM programs. In response, OPGI instituted an Integrated Maintenance Program (IMP) including Reliability Centred Maintenance (RCM) and a PMLP. It should be noted that the PMLP was developed for the 3 OPGI nuclear Sites (i.e. Bruce, Pickering, and Darlington). Effective 1 May 2001, the Bruce Site has been leased to a group of investors lead by British Energy. This paper is written in historical context and therefore refers to the Bruce Site as part of OPGI. The PMLP is made up of five elements: 1) process control, 2) change control, 3) worker feedback, 4) program performance metrics, and 5) deferral module. A PMLP software tool, originally applied to Duke Energy nuclear plants, was enhanced and customized specifically for the OPGI PMLP, and then implemented at all three of OPGI's nuclear sites. The objective of the OPGI PMLP was to: Provide processes/procedures for continual optimization of all site PM tasks, Ensure effective and timely revision of PM tasks in the work management system, Ensure PM tasks remain applicable/effective at all times, Maintain and enhance PM consistency on a component, system and Site basis, Ensure that new predictive maintenance techniques are applied and integrated with the PM program, Ensure that mandated PM tasks are identified and executed, Provide a mechanism for craft feedback, Meet regulatory requirements for PM program effectiveness, and Provide PM task deferral

Relevance of control theory to design and maintenance problems in time-variant reliability: The case of stochastic viability

International Nuclear Information System (INIS)

Rougé, Charles; Mathias, Jean-Denis; Deffuant, Guillaume

2014-01-01

The goal of this paper is twofold: (1) to show that time-variant reliability and a branch of control theory called stochastic viability address similar problems with different points of view, and (2) to demonstrate the relevance of concepts and methods from stochastic viability in reliability problems. On the one hand, reliability aims at evaluating the probability of failure of a system subjected to uncertainty and stochasticity. On the other hand, viability aims at maintaining a controlled dynamical system within a survival set. When the dynamical system is stochastic, this work shows that a viability problem belongs to a specific class of design and maintenance problems in time-variant reliability. Dynamic programming, which is used for solving Markovian stochastic viability problems, then yields the set of design states for which there exists a maintenance strategy which guarantees reliability with a confidence level β for a given period of time T. Besides, it leads to a straightforward computation of the date of the first outcrossing, informing on when the system is most likely to fail. We illustrate this approach with a simple example of population dynamics, including a case where load increases with time. - Highlights: • Time-variant reliability tools cannot devise complex maintenance strategies. • Stochastic viability is a control theory that computes a probability of failure. • Some design and maintenance problems are stochastic viability problems. • Used in viability, dynamic programming can find reliable maintenance actions. • Confronting reliability and control theories such as viability is promising

Research on reliability management systems for Nuclear Power Plant

International Nuclear Information System (INIS)

Maki, Nobuo

2000-01-01

Investigation on a reliability management system for Nuclear Power Plants (NPPs) has been performed on national and international archived documents as well as on current status of studies at Idaho National Engineering and Environmental Laboratory (INEEL), US NPPs (McGuire, Seabrook), a French NPP (St. Laurent-des-Eaux), Japan Atomic Energy Research Institute (JAERI), Central Research Institute of Electric Power Industries (CRIEPI), and power plant manufacturers in Japan. As a result of the investigation, the following points were identified: (i) A reliability management system is composed of a maintenance management system to inclusively manage maintenance data, and an anomalies information and reliability data management system to extract data from maintenance results stored in the maintenance management system and construct a reliability database. (ii) The maintenance management system, which is widely-used among NPPs in the US and Europe, is an indispensable system for the increase of maintenance reliability. (iii) Maintenance management methods utilizing reliability data like Reliability Centered Maintenance are applied for NPP maintenance in the US and Europe, and contributing to cost saving. Maintenance templates are effective in the application process. In addition, the following points were proposed on the design of the system: (i) A detailed database on specifications of facilities and components is necessary for the effective use of the system. (ii) A demand database is indispensable for the application of the methods. (iii) Full-time database managers are important to maintain the quality of the reliability data. (author)

Maintenance strategy based on reliability functions for an oil centrifugal pump

Directory of Open Access Journals (Sweden)

Denis Carlos Mengue

2013-06-01

Full Text Available The purpose of this article was to define the most appropriate maintenance strategy for a centrifugal pump (preventive, predictive, corrective or emergency, based on reliability calculation. The research method was the quantitative modeling, applied in a petroleum plant. The study may contribute to the development of a strategic model for the management of the industrial plant maintenance. In the company's information system, records of eleven years have been gathered on times between failures and times for repair of the equipment. These times were modeled by probability distributions. From the results obtained were calculated Reliability and Maintainability functions R(t and M(t. By combining their expected values (MTBF and MTTR, Av availability was calculated. The figures for MTBF, MTTR and Av were respectively 3,936 hours, 133 hours and 96.73%. The most likely shape factor of the Weibull distribution which modeled the time between failures was 0.69. So, it was possible to affirm that the pump is in the infant mortality phase. The theoretical framework of RCM indicated corrective  maintenance as the strategy for the item. This strategy aims to eliminate the defects of equipment design, reinforce items that usually break and remove the causes of the failures.

Maintenance optimization after RCM

International Nuclear Information System (INIS)

Doyle, E.K.; Lee, C.-G.; Cho, D.

2005-01-01

Variant forms of RCM (Reliability Centered Maintenance) have been the maintenance optimizing tools of choice in industry for the last 20 years. Several such optimization techniques have been implemented at the Bruce Nuclear Station. Further cost refinement of the Station preventive maintenance strategy whereby decisions are based on statistical analysis of historical failure data are now being evaluated. The evaluation includes a requirement to demonstrate that earlier optimization projects have long term positive impacts. This proved to be a significant challenge. Eventually a methodology was developed using Crowe/AMSAA (Army Materials Systems Analysis Activity) plots to justify expenditures on further optimization efforts. (authors)

Optimizing preventive maintenance

International Nuclear Information System (INIS)

DiCola, F.E.

1988-01-01

The traditional approach to preventive maintenance (PM) is based on adherence to manufacturers's requirements and recommended frequencies. When equipment fails, either new procedures are established or the frequency is increased. This leads to an increase in the number of PM activities, overloading not only maintenance resources, but support as well. There is no correlation between more PM and an increase in equipment reliability. More PM may actually induce failures. Reliability-centered maintenance, a new concept in utility maintenance, is based on identifying system/subsystem functions, failures, and dominant failure modes to develop or revise PM tasks. The activities described in this paper are based on actual implementation of this concept on an ongoing project to upgrade the PM program at one of the largest electric utilities in the country. Optimum PM activities are those that, when implemented, will minimize factors that c cause equipment to fail. One technique described illustrates how equipment performance, failure modes, and causes can be related to minimize the occurrence of failures. Operating history and service life of a component are key factors in determining the most effective PM activities, provided that the factors are related to failure modes and causes

20 CFR 638.306 - Protection and maintenance of contract center facilities owned or leased by Job Corps.

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Protection and maintenance of contract center... Funding, Site Selection, and Facilities Management § 638.306 Protection and maintenance of contract center... and maintenance of contract center facilities owned or leased by Job Corps which shall be consistent...

Maintenance for the Millennium: Another Approach

International Nuclear Information System (INIS)

Sculthorpe, Barruy R.

2002-01-01

Nuclear units nationwide are struggling to increase plant reliability and availability while at the same time reduce their operating and maintenance costs. Some very costly investments have been made in programs such as Reliability Centered Maintenance [RCM]. Florida Power and Light's approach at the St. Lucie Nuclear Plant has taken a slightly different approach. Building on our knowledge of the RCM process and an already existing 'World Class' Predictive Maintenance Program, a 'Condition-Based' Maintenance Program that takes advantage of the RCM philosophy and our toolbox full of advanced and highly successful predictive maintenance technologies. These tools currently consist of vibration analysis, lubricant analysis (both physical property and wear metals analysis, thermographic analysis, motor current signature analysis, tribology and process parameter trending. All employed with the intent to evaluate a machines health. This machine health check allows the forecasting of future preventative maintenance [PM's] tasks and the revision of existing PM's to maximize machine performance and eliminate 'no-value-added' maintenance activities/costs. Within the last year, the Condition-Based Maintenance Program has produced a cost saving of approximately $1.5 million dollars. As the program matures, these cost savings will accumulate well into the millennium. (authors)

Reliability-Based Planning of Inspection, Operation and Maintenance for Offshore Oil & Gas Structures and Wind Turbines

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard

2011-01-01

Reliability-based cost-optimal planning of inspection, maintenance and operation has many applications. In this paper applications for planning of inspections for oil & gas jacket structures and of operation and maintenance of offshore wind turbines are described and illustrated by examples....

An information system supporting design for reliability and maintenance

International Nuclear Information System (INIS)

Rit, J.F.; Beraud, M.T.

1997-01-01

EDF is currently developing a methodology to integrate availability, operating experience and maintenance in the design of power plants. This involves studies that depend closely on the results and assumptions of each other about the reliability and operations of the plant. Therefore a support information system must be carefully designed. Concurrently with development of the methodology, a research oriented information system was designed and built. It is based on the database model of a logistic support repository that we tailored to our needs. (K.A.)

An information system supporting design for reliability and maintenance

Energy Technology Data Exchange (ETDEWEB)

Rit, J.F.; Beraud, M.T

1997-12-31

EDF is currently developing a methodology to integrate availability, operating experience and maintenance in the design of power plants. This involves studies that depend closely on the results and assumptions of each other about the reliability and operations of the plant. Therefore a support information system must be carefully designed. Concurrently with development of the methodology, a research oriented information system was designed and built. It is based on the database model of a logistic support repository that we tailored to our needs. (K.A.) 10 refs.

Systematic maintenance analysis with decision support method and tool for optimizing maintenance programme

International Nuclear Information System (INIS)

Laakso, K.; Simola, K.; Dorrepaal, J.; Skogberg, P.

1999-01-01

This report describes an approach to evaluate the effectiveness of test and maintenance programs of technical systems used during several years. The method combines an analysis of the historical data on faults and repairs with an analysis of the history of periodic testing and preventive maintenance action programs. The application of the maintenance analysis from the methodological point of view in the reliability centered maintenance (RCM) project for Barsebaeck nuclear power plant is described. In order to limit the analysis resources, a method for ranking of objects for maintenance analysis is needed. Preliminary suggestions for changes in maintenance action programs are based on signals from simple maintenance indicators and qualitative analysis of underlying data on failures and maintenance. To facilitate generation of maintenance indicators, and make the maintenance analysis more efficient, a powerful and suitable data treatment tool is needed for analysis of the work order history. In the final maintenance decisions, additional decision criteria must be taken into account, and thus a more formal decision analysis is often needed for decision support. (au)

Methods and tools in development in the field of maintenance; Methodes et outils pour la maintenance en cours de developpement

Energy Technology Data Exchange (ETDEWEB)

Le Reverend, D.; Tortolano, M. [Electricite de France (EDF/RD), 78 - Chatou (France); Leniaud, F. [Electricite de France (EDF), Div. Production Nuleaire, 93 - Saint-Denis (France)

2004-07-01

This article is dedicated to the maintenance strategy followed by EDF for its nuclear power plants. This strategy is based on the American method RCM (reliability centered method) that has been extended to passive components such as structures and relies on 4 axis. The first axis can be defined as the optimization of maintenance with regard to safety, outage and costs. The aim is to set the border between preventive maintenance and remedial maintenance. The second axis is the condition based maintenance that is the maintenance action that is triggered by the real state of the equipment. This type of maintenance implies the search for reliable and accurate diagnostics. The third axis is the design of simulation and planning tools required for the management of the moving of tools, machinery and spare-parts on a maintenance work site. The fourth axis is the design of tools able to repair some important equipment, this way may be a valid alternative to the replacement of equipment in terms of cost and outage time. (A.C.)

Utilizing reliability concepts in the development of IEEE recommended good practices for nuclear plant maintenance

International Nuclear Information System (INIS)

Gradin, L.P.

1986-01-01

This paper presents information describing the concern for nuclear power plant electrical equipment maintenance and the IEEE Nuclear Power Engineering Committee's method to address that concern. That method includes the creation of Working Group 3.3, ''Maintenance Good Practices'' which is developing specific maintenance good practice documents, supporting technical information exchange, and providing a vehicle to promote practices which can reduce cost and enhance plant safety. The foundation for that effort is the utilization of Reliability concepts

Modeling the reliability and maintenance costs of wind turbines using Weibull analysis

Energy Technology Data Exchange (ETDEWEB)

Vachon, W.A. [W.A. Vachon & Associates, Inc., Manchester, MA (United States)

1996-12-31

A general description is provided of the basic mathematics and use of Weibull statistical models for modeling component failures and maintenance costs as a function of time. The applicability of the model to wind turbine components and subsystems is discussed with illustrative examples of typical component reliabilities drawn from actual field experiences. Example results indicate the dominant role of key subsystems based on a combination of their failure frequency and repair/replacement costs. The value of the model is discussed as a means of defining (1) maintenance practices, (2) areas in which to focus product improvements, (3) spare parts inventory, and (4) long-term trends in maintenance costs as an important element in project cash flow projections used by developers, investors, and lenders. 6 refs., 8 figs., 3 tabs.

Nuclear power generating station operability assurance reliability, availability, and maintainability application for maintenance management

International Nuclear Information System (INIS)

Cleveland, J.W.; Regenie, T.R.; Wilson, R.J.

1985-01-01

Environmental qualification and equipment warrantee insurance stipulations should be supplemented with a reliable maintainability program structured to identify and control fast failing subcomponents within critical equipment. Anticipation of equipment subcomponent failures can control unnecessary plant off-line occurrences. Incorporation of reliability, availability, and maintainability considerations into plant maintenance policies on power generation and safety related items have positive cost benefit advantages

Maintenance personnel performance simulation (MAPPS): a model for predicting maintenance performance reliability in nuclear power plants

International Nuclear Information System (INIS)

Knee, H.E.; Krois, P.A.; Haas, P.M.; Siegel, A.I.; Ryan, T.G.

1983-01-01

The NRC has developed a structured, quantitative, predictive methodology in the form of a computerized simulation model for assessing maintainer task performance. Objective of the overall program is to develop, validate, and disseminate a practical, useful, and acceptable methodology for the quantitative assessment of NPP maintenance personnel reliability. The program was organized into four phases: (1) scoping study, (2) model development, (3) model evaluation, and (4) model dissemination. The program is currently nearing completion of Phase 2 - Model Development

MAPPS (Maintenance Personnel Performance Simulation): a computer simulation model for human reliability analysis

International Nuclear Information System (INIS)

Knee, H.E.; Haas, P.M.

1985-01-01

A computer model has been developed, sensitivity tested, and evaluated capable of generating reliable estimates of human performance measures in the nuclear power plant (NPP) maintenance context. The model, entitled MAPPS (Maintenance Personnel Performance Simulation), is of the simulation type and is task-oriented. It addresses a number of person-machine, person-environment, and person-person variables and is capable of providing the user with a rich spectrum of important performance measures including mean time for successful task performance by a maintenance team and maintenance team probability of task success. These two measures are particularly important for input to probabilistic risk assessment (PRA) studies which were the primary impetus for the development of MAPPS. The simulation nature of the model along with its generous input parameters and output variables allows its usefulness to extend beyond its input to PRA

Random maintenance policies

CERN Document Server

Nakagawa, Toshio

2014-01-01

Exploring random maintenance models, this book provides an introduction to the implementation of random maintenance, and it is one of the first books to be written on this subject.  It aims to help readers learn new techniques for applying random policies to actual reliability models, and it provides new theoretical analyses of various models including classical replacement, preventive maintenance and inspection policies. These policies are applied to scheduling problems, backup policies of database systems, maintenance policies of cumulative damage models, and reliability of random redundant systems. Reliability theory is a major concern for engineers and managers, and in light of Japan’s recent earthquake, the reliability of large-scale systems has increased in importance. This also highlights the need for a new notion of maintenance and reliability theory, and how this can practically be applied to systems. Providing an essential guide for engineers and managers specializing in reliability maintenance a...

Logistics Operations Management Center: Maintenance Support Baseline (LOMC-MSB)

Science.gov (United States)

Kurrus, R.; Stump, F.

1995-01-01

The Logistics Operations Management Center Maintenance Support Baseline is defined. A historical record of systems, applied to and deleted from, designs in support of future management and/or technical analysis is provided. All Flight elements, Ground Support Equipment, Facility Systems and Equipment and Test Support Equipment for which LOMC has responsibilities at Kennedy Space Center and other locations are listed. International Space Station Alpha Program documentation is supplemented. The responsibility of the Space Station Launch Site Support Office is established.

Reliability and risk-based planning of operation and maintenance of offshore wind turbines

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard; Florian, Mihai; Berzonskis, Arvydas

2016-01-01

costly (and safe), and it is important to include in the reliability assessment the information obtained during operation (from condition monitoring and inspections) and the maintenance performed (incl. repairs and replacements). The paper presents a risk-based approach for optimal planning of Operation...

Maintenance strategy for tilting table of rolling mill based on reliability considerations

International Nuclear Information System (INIS)

Deshpande, V.S.; Modak, J.P.

2003-01-01

Reliability centred maintenance (RCM) is a new strategic framework for ensuring that any asset continues to perform, as its users want it to perform. RCM is a process used to determine the maintenance requirement of any physical asset in its operating context. RCM process entails asking seven questions about each of the selected assets. It makes use of two documents namely, RCM information worksheet and RCM decision worksheet. RCM decision diagram integrates all the decision processes into a single strategic framework. RCM concept developed by US commercial airlines industry has been successfully implemented by Military, Navy, Nuclear power plants, electric power generation and distribution undertakings and several other sectors. These projects have been carried out in the United Kingdom, The Republic of Ireland, the United States, Hong Kong, Australia, Spain and Singapore. The fact that people has enthusiastically received RCM at all levels and has enabled users to achieve some remarkable successes in all of these countries, suggests that it can be universally employed. Literature review indicates that RCM approach is not conventionally applied in process industries in India. Presently, predictive maintenance (PDM) approach along with conventional preventive maintenance is used in continuous/process industries. This approach if implemented in totality will increase the production cost to a large degree and make the production uneconomical. Similarly breakdown maintenance (BDM) approach cannot be applied in such industries as each breakdown involves huge costs. RCM approach is a compromise between PDM and BDM approach for optimising the cost and ensuring the availability of machine. The RCM approach has been applied to the tilting table system of rolling mill for the research work reported in this paper. In the present study, preventive maintenance tasks suggested for power transmission subsystem, guiding and transportation subsystem and hydraulic subsystem in

[STRATEGY OF USE AND MAINTENANCE OF CLINICAL HOSPITAL CENTER RIJEKA IN ACCORDANCE WITH KEY PERFORMANCE INDICATORS FOR STRATEGIC HEALTHCARE FACILITIES MAINTENANCE].

Science.gov (United States)

Sjekavica, Mariela; Haller, Herman; Cerić, Anita

2015-01-01

Building usage is the phase in the building life cycle that is most time-consuming, most functional, most significant due to building purpose and often systematically ignored. Maintenance is the set of activities that ensure the planned duration of facility exploitation phase in accordance with the requirements for quality maintenance of a large number of important building features as well as other elements immanent to the nature of facilities' life. The aim of the study is to show the analysis of the current state of organized, planned and comprehensive managerial approach in hospital utilization and maintenance in the Republic of Croatia, given on the case study of Clinical hospital center in Rijeka. The methodology used consists of relevant literature section of theory of facility utilization, maintenance and management in general, hospital buildings especially, display of practice on case study, and comparison of key performance indicators values obtained through interview with those that author Igal M. Shohet defined in his study by field surveys and statistical analyses. Despite many positive indicators of Clinical hospital center Rijeka maintenance, an additional research is needed in order to define a more complete national hospital maintenance strategy.

Breaker Maintenance: Volume 3, Molded-Case circuit breakers

International Nuclear Information System (INIS)

Davis, E.L.; Funk, D.L.

1991-09-01

Modeled-case circuit breakers (MCCBs) provide power and circuit protection in nuclear plant electrical distribution systems. Thus, their proper operation is essential to the safe and reliable operation of plant electrical distribution systems. This guide for both nuclear and non-nuclear power generating facilities will help improve the maintenance and reliability of MCCBs. The authors developed this guide to establish a working-level understanding of hardware performance trends, reliability, and failure modes from which maintenance practices could be specified. The first step in preparing this guide was an in-depth review of available operating experience and failure data, which was obtained from nuclear information sources such as EPRI's Nuclear Maintenance Applications Center. In addition, they evaluated some nonnuclear reliability data. Next, they investigated current industry practices, including a review of manufacturer's recommendations and numerous industry standards. Finally, they used the collective information to develop programmatic recommendations and, where appropriate, detailed inspection and test guidance. This guide offers many recommendations applicable to MCCB maintenance, such as an engineering description of MCCBs and their operation; an overview of reliability and failure data; programmatic recommendations, including inspection and test periodicity; detailed inspection and test guidance; and corrective maintenance recommendations. Supplementary information includes an overview of industry standards, a discussion of regulatory issues, and sample data sheets. An evaluation of operating experience indicates that a maintenance program need not be overly complicated to detect the predominant failure modes associated with MCCBs. Those implementating an MCCB maintenance and testing program, however, must recognize the inherent limitations associated with field-testing of these devices. 42 refs., 17 figs., 7 tabs

Reliability Evaluation of Machine Center Components Based on Cascading Failure Analysis

Science.gov (United States)

Zhang, Ying-Zhi; Liu, Jin-Tong; Shen, Gui-Xiang; Long, Zhe; Sun, Shu-Guang

2017-07-01

In order to rectify the problems that the component reliability model exhibits deviation, and the evaluation result is low due to the overlook of failure propagation in traditional reliability evaluation of machine center components, a new reliability evaluation method based on cascading failure analysis and the failure influenced degree assessment is proposed. A direct graph model of cascading failure among components is established according to cascading failure mechanism analysis and graph theory. The failure influenced degrees of the system components are assessed by the adjacency matrix and its transposition, combined with the Pagerank algorithm. Based on the comprehensive failure probability function and total probability formula, the inherent failure probability function is determined to realize the reliability evaluation of the system components. Finally, the method is applied to a machine center, it shows the following: 1) The reliability evaluation values of the proposed method are at least 2.5% higher than those of the traditional method; 2) The difference between the comprehensive and inherent reliability of the system component presents a positive correlation with the failure influenced degree of the system component, which provides a theoretical basis for reliability allocation of machine center system.

A survey of research projects in maintenance optimization for Electricite de France power plants

International Nuclear Information System (INIS)

Jacquot, J.P.

1996-01-01

Six years ago, Electricite de France launched a Reliability Centered Maintenance (RCM) pilot project to optimize preventive maintenance for its nuclear power plants. After a feasibility study, a Reliability Centered Maintenance (RCM) method was standardized. It is now applied on a large scale to the 50 EDF nuclear units. A RCM workstation based on this standardized method has been developed and is now used in each plant. In the next step, the author will consider whether a risk based approach can be included in this RCM process in order to analyze critical passive components such as pipes and supports. Considering the potential advantages of these optimization techniques, a dedicated process has been also developed for maintenance of future plants, gas turbines, or nuclear units. For these future plants, a Logistic Support Analysis (LSA) will be added to the RCM process to globally evaluate availability, safety and maintenance costs. This paper will present a survey of these different developments of methods and tools

Reliability Assessment and Reliability-Based Inspection and Maintenance of Offshore Wind Turbines

DEFF Research Database (Denmark)

Ramirez, José Rangel

actions are the most relevant and effective means of control of deterioration. The risk-based inspection planning methodology, based on Bayesian decision theory, represents an important tool to identify the suitable strategy to inspect and control the deterioration in structures such as offshore wind...... performance during the life cycle. The deterioration processes, such as fatigue and corrosion, are typically affecting offshore structural systems. This damage decreases the system performance and increases the risk of failure, thus not fulfilling the established safety criteria. Inspection and maintenance...... to their offshore location, no pollution risks and low human risks since they are unmanned. This allows the allocation of lower reliability level compared to e.g. oil & gas installations. With the incursion to water depths between 20 and 50 meters, the use of jacket and tripod structures represents a feasible...

Reliability And Maintenance Analysis Of CCTV Systems Used In Rail Transport

OpenAIRE

Siergiejczyk Mirosław; Paś Jacek; Rosiński Adam

2015-01-01

CCTV systems are widely used across plethora of industrial areas including transport, where their function is to support transport telematics systems. Among others, they are used to ensure travel safety. This paper presented a reliability and maintenance analysis of CCTV. It led to building a relationships graph and then Chapman–Kolmogorov system of equations was derived to describe it. Drawing on those equations, relationships for calculating probability of system staying in state of full ab...

Wind turbine reliability :understanding and minimizing wind turbine operation and maintenance costs.

Energy Technology Data Exchange (ETDEWEB)

Walford, Christopher A. (Global Energy Concepts. Kirkland, WA)

2006-03-01

Wind turbine system reliability is a critical factor in the success of a wind energy project. Poor reliability directly affects both the project's revenue stream through increased operation and maintenance (O&M) costs and reduced availability to generate power due to turbine downtime. Indirectly, the acceptance of wind-generated power by the financial and developer communities as a viable enterprise is influenced by the risk associated with the capital equipment reliability; increased risk, or at least the perception of increased risk, is generally accompanied by increased financing fees or interest rates. This paper outlines the issues relevant to wind turbine reliability for wind turbine power generation projects. The first sections describe the current state of the industry, identify the cost elements associated with wind farm O&M and availability and discuss the causes of uncertainty in estimating wind turbine component reliability. The latter sections discuss the means for reducing O&M costs and propose O&M related research and development efforts that could be pursued by the wind energy research community to reduce cost of energy.

Reliability engineering

International Nuclear Information System (INIS)

Lee, Chi Woo; Kim, Sun Jin; Lee, Seung Woo; Jeong, Sang Yeong

1993-08-01

This book start what is reliability? such as origin of reliability problems, definition of reliability and reliability and use of reliability. It also deals with probability and calculation of reliability, reliability function and failure rate, probability distribution of reliability, assumption of MTBF, process of probability distribution, down time, maintainability and availability, break down maintenance and preventive maintenance design of reliability, design of reliability for prediction and statistics, reliability test, reliability data and design and management of reliability.

Upgrade of maintenance technologies of Nuclear Power Plants

International Nuclear Information System (INIS)

Kamada, Kazuaki

2005-01-01

In order to enhance long-term safe and stable operation of Ikata Nuclear Power Plants (NPPs) in more efficient way, maintenance technology upgrade project was started aiming at establishment of simplified and efficient self-maintenance system with affiliated companies. Maintenance technique and supervisor qualification system was introduced after improvement and reinforcement of personnel education and training. Reflecting investigation of maintenance activities of US NPPs and productivity improvement in other industries, preventive maintenance optimization project had been performed such as introduction of key performance indicator (KPI), new system incorporating reliability-centered maintenance (RCM) and condition-based maintenance (CBM), and on-line monitoring and maintenance (OLM) based on risk assessment. Enterprise asset management (EAM) to establish information data base and total productive maintenance (TPM) action for every personnel to participate in self-maintenance was also introduced. (T. Tanaka)

Safety of nuclear operation and maintenance

International Nuclear Information System (INIS)

Mori, M.; Nitta, T.; Sakai, K.

1994-01-01

The Kansai Electric Power Co. Inc.(Kansai EPC) aims to pursue a high quality and highly reliable operation in nuclear power generation in order to ensure safety by reducing the risk of accidents and win the confidence from the society and the public. It is emphasised that in order to realize this aim manufacturers and contractors cooperate with each other in performing high quality maintenance through plant lifetime maintenance system. TQC (Total Quality Control) activity enhances the motivation for each individual to have a quality-oriented mind and cultivate the safety culture. Under the lifetime employment practice, Kansai EPC and maintenance contractors can conduct systematic education and training, and the Maintenance Training Center helps to make it effective. 6 figs

The importance of maintainability in maintenance cost management

International Nuclear Information System (INIS)

Allen, R.R.

1996-01-01

This paper provides specific examples and results from ongoing projects at Power Plants, and for offshore oil platforms. The paper describes the vital role maintainability has on plant availability. How the application of equipment maintainability principles, if addressed using state of the art computer tools and advanced business processes can bring annual return on investment results as high as 15 to 1. The maintenance process of today and for the future must provide for high plant availability at the lowest possible cost. The high cost of obtaining equipment reliability levels necessary to meet required availability demands has not proved to be sustainable. Therefore new business decision processes that address equipment failures as part of the maintenance process have been developed. Repair costs require that equipment failures be selective and controlled so that a high level of safety and plant availability is assurance. This can only be accomplished by the use of advanced computer tools in the hands of well trained maintenance-engineering specialist. The relationship between Reliability Centered Maintenance (RCM), Condition Directed Planned Maintenance (CDPM), and maintainability is also presented

Probability distribution of machining center failures

International Nuclear Information System (INIS)

Jia Yazhou; Wang Molin; Jia Zhixin

1995-01-01

Through field tracing research for 24 Chinese cutter-changeable CNC machine tools (machining centers) over a period of one year, a database of operation and maintenance for machining centers was built, the failure data was fitted to the Weibull distribution and the exponential distribution, the effectiveness was tested, and the failure distribution pattern of machining centers was found. Finally, the reliability characterizations for machining centers are proposed

Nuclear power plant maintenance personnel reliability prediction (NPP/MPRP) effort at Oak Ridge National Laboratory

International Nuclear Information System (INIS)

Knee, H.E.; Haas, P.M.; Siegel, A.I.

1981-01-01

Human errors committed during maintenance activities are potentially a major contribution to the overall risk associated with the operation of a nuclear power plant (NPP). An NRC-sponsored program at Oak Ridge National Laboratory is attempting to develop a quantitative predictive technique to evaluate the contribution of maintenance errors to the overall NPP risk. The current work includes a survey of the requirements of potential users to ascertain the need for and content of the proposed quantitative model, plus an initial job/task analysis to determine the scope and applicability of various maintenance tasks. In addition, existing human reliability prediction models are being reviewed and assessed with respect to their applicability to NPP maintenance tasks. This paper discusses the status of the program and summarizes the results to date

Reliability Centred Maintenance (RCM) Analysis of Laser Machine in Filling Lithos at PT X

Science.gov (United States)

Suryono, M. A. E.; Rosyidi, C. N.

2018-03-01

PT. X used automated machines which work for sixteen hours per day. Therefore, the machines should be maintained to keep the availability of the machines. The aim of this research is to determine maintenance tasks according to the cause of component’s failure using Reliability Centred Maintenance (RCM) and determine the amount of optimal inspection frequency which must be performed to the machine at filling lithos process. In this research, RCM is used as an analysis tool to determine the critical component and find optimal inspection frequencies to maximize machine’s reliability. From the analysis, we found that the critical machine in filling lithos process is laser machine in Line 2. Then we proceed to determine the cause of machine’s failure. Lastube component has the highest Risk Priority Number (RPN) among other components such as power supply, lens, chiller, laser siren, encoder, conveyor, and mirror galvo. Most of the components have operational consequences and the others have hidden failure consequences and safety consequences. Time-directed life-renewal task, failure finding task, and servicing task can be used to overcome these consequences. The results of data analysis show that the inspection must be performed once a month for laser machine in the form of preventive maintenance to lowering the downtime.

A Primer for DoD Reliability, Maintainability, Safety, and Logistics Standards, 1992

Science.gov (United States)

1991-10-01

Application of Reliability-Centered Maintenance to Naval Aircraft Weapon Systems and Support Equipment "* FMD -91 Failure Mode/Mechanism...Distributions ( FMD -91) available from the Reliability Analysis Center, HIT Research Institute, 201 Mill St., Rome, NY 13440-8200. 14.4 PHYSICAL...Fault Tree Analysis ( FTA ) (9) Sneak Circuit Analysis (10) Design Reviews Items (1) and (2) are addressed in Section 7 largely by reference to MIL

DATMAN: A reliability data analysis program using Bayesian updating

International Nuclear Information System (INIS)

Becker, M.; Feltus, M.A.

1996-01-01

Preventive maintenance (PM) techniques focus on the prevention of failures, in particular, system components that are important to plant functions. Reliability-centered maintenance (RCM) improves on the PM techniques by introducing a set of guidelines by which to evaluate the system functions. It also minimizes intrusive maintenance, labor, and equipment downtime without sacrificing system performance when its function is essential for plant safety. Both the PM and RCM approaches require that system reliability data be updated as more component failures and operation time are acquired. Systems reliability and the likelihood of component failures can be calculated by Bayesian statistical methods, which can update these data. The DATMAN computer code has been developed at Penn State to simplify the Bayesian analysis by performing tedious calculations needed for RCM reliability analysis. DATMAN reads data for updating, fits a distribution that best fits the data, and calculates component reliability. DATMAN provides a user-friendly interface menu that allows the user to choose from several common prior and posterior distributions, insert new failure data, and visually select the distribution that matches the data most accurately

Opportunistic or event-driven maintenance at the Stanford Linear Accelerator Center

International Nuclear Information System (INIS)

Allen, C.W.; Anderson, S.; Erickson, R.; Linebarger, W.; Sheppard, J.C.; Stanek, M.

1997-03-01

The Stanford Linear Accelerator Center (SLAC) uses a maintenance management philosophy that is best described as opportunistic or event-driven. Opportunistic maintenance can be defined as a systematic method of collecting, investigating, pre-planning, and publishing a set of proposed maintenance tasks and acting on them when there is an unscheduled failure or repair ''opportunity''. Opportunistic maintenance can be thought of as a modification of the run-to-fail maintenance management philosophy. This maintenance plan was adopted and developed to improve the overall availability of SLAC's linear accelerator, beam delivery systems, and associated controls, power systems, and utilities. In the late 1980's, as the technical complexity of the accelerator facility increased, variations on a conventional maintenance plan were used with mixed results. These variations typically included some type of regular periodic interruption to operations. The periodic shutdowns and unscheduled failures were additive and resulted in unsatisfactory availability. Maintenance issues are evaluated in a daily meeting that includes the accelerator managers, maintenance supervisors and managers, safety office personnel, program managers, and accelerator operators. Lists of pending maintenance tasks are made available to the general SLAC population by a World Wide Web site on a local internet. A conventional information system which pre-dates the WWW site is still being used to provide paper copies to groups that are not yet integrated into the WWW system. The local internet provides real time maintenance information, allowing people throughout the facility to track progress on tasks with essentially real-time status updates. With the introduction of opportunistic maintenance, the accelerator's availability has been measurably better. This paper will discuss processes, rolls and responsibilities of key maintenance groups, and management tools developed to support opportunistic maintenance

Global optimization of maintenance and surveillance testing based on reliability and probabilistic safety assessment. Research project

International Nuclear Information System (INIS)

Martorell, S.; Serradell, V.; Munoz, A.; Sanchez, A.

1997-01-01

Background, objective, scope, detailed working plan and follow-up and final product of the project ''Global optimization of maintenance and surveillance testing based on reliability and probabilistic safety assessment'' are described

Design of fuel cell powered data centers for sufficient reliability and availability

Science.gov (United States)

Ritchie, Alexa J.; Brouwer, Jacob

2018-04-01

It is challenging to design a sufficiently reliable fuel cell electrical system for use in data centers, which require 99.9999% uptime. Such a system could lower emissions and increase data center efficiency, but the reliability and availability of such a system must be analyzed and understood. Currently, extensive backup equipment is used to ensure electricity availability. The proposed design alternative uses multiple fuel cell systems each supporting a small number of servers to eliminate backup power equipment provided the fuel cell design has sufficient reliability and availability. Potential system designs are explored for the entire data center and for individual fuel cells. Reliability block diagram analysis of the fuel cell systems was accomplished to understand the reliability of the systems without repair or redundant technologies. From this analysis, it was apparent that redundant components would be necessary. A program was written in MATLAB to show that the desired system reliability could be achieved by a combination of parallel components, regardless of the number of additional components needed. Having shown that the desired reliability was achievable through some combination of components, a dynamic programming analysis was undertaken to assess the ideal allocation of parallel components.

Non-periodic preventive maintenance with reliability thresholds for complex repairable systems

International Nuclear Information System (INIS)

Lin, Zu-Liang; Huang, Yeu-Shiang; Fang, Chih-Chiang

2015-01-01

In general, a non-periodic condition-based PM policy with different condition variables is often more effective than a periodic age-based policy for deteriorating complex repairable systems. In this study, system reliability is estimated and used as the condition variable, and three reliability-based PM models are then developed with consideration of different scenarios which can assist in evaluating the maintenance cost for each scenario. The proposed approach provides the optimal reliability thresholds and PM schedules in advance by which the system availability and quality can be ensured and the organizational resources can be well prepared and managed. The results of the sensitivity anlysis indicate that PM activities performed at a high reliability threshold can not only significantly improve the system availability but also efficiently extend the system lifetime, although such a PM strategy is more costly than that for a low reliabiltiy threshold. The optimal reliability threshold increases along with the number of PM activities to prevent future breakdowns caused by severe deterioration, and thus substantially reduces repair costs. - Highlights: • The PM problems for repairable deteriorating systems are formulated. • The structural properties of the proposed PM models are investigated. • The corresponding algorithms to find the optimal PM strategies are provided. • Imperfect PM activities are allowed to reduce the occurences of breakdowns. • Provide managers with insights about the critical factors in the planning stage

Effect of amplifier component maintenance on laser system availability and reliability for the US National Ignition Facility

International Nuclear Information System (INIS)

Erlandson, A.C.; Lambert, H.; Zapata, L.E.

1996-12-01

We have analyzed the availability and reliability of the flashlamp-pumped, Nd:glass amplifiers that, as a part of a laser now being designed for future experiments, in inertial confinement fusion (ICF), will be used in the National Ignition Facility (NIF). Clearly , in order for large ICF systems such as the NIF to operate effectively as a whole, all components must meet demanding availability and reliability requirements. Accordingly, the NIF amplifiers can achieve high reliability and availability by using reliable parts, and by using a cassette-based maintenance design that allows most key amplifier parts to be 1744 replaced within a few hours. In this way, parts that degrade slowly, as the laser slabs, silver reflectors, and blastshields can be expected to do, based on previous experience, can be replaced either between shots or during scheduled maintenance periods, with no effect on availability or reliability. In contrast, parts that fail rapidly, such as the flashlamps, can and do cause unavailability or unreliability. Our analysis demonstrates that the amplifiers for the NIF will meet availability and reliability goals, respectively, of 99.8% and 99.4%, provided that the 7680 NIF flashlamps in NIF have failure rates of less than, or equal to, those experienced on Nova, a 5000-lamp laser at Lawrence Livermore National Laboratory (LLNL)

Reliability analysis and risk-based methods for planning of operation & maintenance of offshore wind turbines

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard

2017-01-01

for extreme and fatigue limit states are presented. Operation & Maintenance planning often follows corrective and preventive strategies based on information from condition monitoring and structural health monitoring systems. A reliability- and risk-based approach is presented where a life-cycle approach...

Optimization of maintenance programme at Daya Bay Nuclear Power Station based on RCM analysis results

International Nuclear Information System (INIS)

Liu Min

2003-01-01

This paper begins with an introduction to Guangdong Daya Bay Nuclear Power Station (GNPS) and gives a simple introduction to the operations and maintenance documentation system at GNPS. It then will review the maintenance program guidelines base and the associated problems prior to the application of reliability centered maintenance (RCM). How RCM was implemented at GNPS, how the results of RCM analysis were used to optimize the maintenance program and test program, and what is the interface between RCM and the existing maintenance program will be shown. Next, it will show the successful implementation of RCM at GNPS resulted in the following changes: A new understanding of equipment failure challenges operations and maintenance beliefs, maintenance concepts undergo a large change, maintenance program and periodic testing program are continuously modified and optimized, new on-condition maintenance technologies are introduced, non-productive scheduled overhauls are discarded, maintenance costs are effectively controlled, maintenance appropriateness has improved, management of hidden failures is more effective and timely. It will show the benefit of greater equipment reliability brought about by all of these changes, which in turn increases the reliability and safety of the entire power station. (author)

Good practices for cost effective maintenance of nuclear power plants

International Nuclear Information System (INIS)

1997-02-01

This publication is organized around five areas that were identified by the utilities and government organizations who contributed to this report as most important to them. They are: Increasing production through maintenance activities related to improved plant material condition, reduced duration of planned outages, use of on-line maintenance and reduced frequency of forced outages; reducing workload through avoiding unnecessary regulatory burden and using reliability centered maintenance and condition monitoring; improving maintenance processes through better planning and scheduling, use of information management systems, graduated work controls, and appropriate post-maintenance testing; improving productivity through better teamwork, greater sharing of resources, and better radiation management associated with maintenance; measuring performance of maintenance activities through such tools as performance measures and benchmarking. Figs, tabs

Reliability-based optimization of maintenance scheduling of mechanical components under fatigue

Science.gov (United States)

Beaurepaire, P.; Valdebenito, M.A.; Schuëller, G.I.; Jensen, H.A.

2012-01-01

This study presents the optimization of the maintenance scheduling of mechanical components under fatigue loading. The cracks of damaged structures may be detected during non-destructive inspection and subsequently repaired. Fatigue crack initiation and growth show inherent variability, and as well the outcome of inspection activities. The problem is addressed under the framework of reliability based optimization. The initiation and propagation of fatigue cracks are efficiently modeled using cohesive zone elements. The applicability of the method is demonstrated by a numerical example, which involves a plate with two holes subject to alternating stress. PMID:23564979

The nuclear power plant maintenance personnel reliability prediction (NPP/MPRP) effort at Oak Ridge National Laboratory

International Nuclear Information System (INIS)

Knee, H.E.; Haas, P.M.; Siegel, A.I.

1982-01-01

Human errors committed during maintenance activities are potentially a major contribution to the overall risk associated with the operation of a nuclear power plant (NPP). An NRC-sponsored program at Oak Ridge National Laboratory is attempting to develop a quantitative predictive technique to evaluate the contribution of maintenance errors to the overall NPP risk. The current work includes a survey of the requirements of potential users to ascertain the need for and content of the proposed quantitative model, plus an initial job/task analysis to determine the scope and applicability of various maintenance tasks. In addition, existing human reliability prediction models are being reviewed and assessed with respect to their applicability to NPP maintenance tasks. This paper discusses the status of the program and summarizes the results to date

Methods for Calculating Frequency of Maintenance of Complex Information Security System Based on Dynamics of Its Reliability

Science.gov (United States)

Varlataya, S. K.; Evdokimov, V. E.; Urzov, A. Y.

2017-11-01

This article describes a process of calculating a certain complex information security system (CISS) reliability using the example of the technospheric security management model as well as ability to determine the frequency of its maintenance using the system reliability parameter which allows one to assess man-made risks and to forecast natural and man-made emergencies. The relevance of this article is explained by the fact the CISS reliability is closely related to information security (IS) risks. Since reliability (or resiliency) is a probabilistic characteristic of the system showing the possibility of its failure (and as a consequence - threats to the protected information assets emergence), it is seen as a component of the overall IS risk in the system. As it is known, there is a certain acceptable level of IS risk assigned by experts for a particular information system; in case of reliability being a risk-forming factor maintaining an acceptable risk level should be carried out by the routine analysis of the condition of CISS and its elements and their timely service. The article presents a reliability parameter calculation for the CISS with a mixed type of element connection, a formula of the dynamics of such system reliability is written. The chart of CISS reliability change is a S-shaped curve which can be divided into 3 periods: almost invariable high level of reliability, uniform reliability reduction, almost invariable low level of reliability. Setting the minimum acceptable level of reliability, the graph (or formula) can be used to determine the period of time during which the system would meet requirements. Ideally, this period should not be longer than the first period of the graph. Thus, the proposed method of calculating the CISS maintenance frequency helps to solve a voluminous and critical task of the information assets risk management.

Reliability-based maintenance evaluations and standard preventive maintenance programs

International Nuclear Information System (INIS)

Varno, M.; McKinley, M.

1993-01-01

Due to recent issuance of 10CFR50.65, the U.S. Nuclear Regulatory Commission maintenance rule (Rule), and the open-quotes Industry Guideline for Monitoring the Effectiveness of Maintenance at Nuclear Power Plantsclose quotes prepared by the Nuclear Management and Resources Council, many utilities are undertaking review or evaluation of current preventive maintenance (PM) programs. Although PM optimization and documentation are not specifically required by the Rule, an appropriate and effective PM program (PMP) will be the cornerstone of the successful and cost-effective implementation of the Rule. Currently, a project is being conducted at the Vermont Yankee Nuclear Power Station (VYNPS) in conjunction with Quadrex Energy Services to evaluate, optimize, and document the PMP. The project began in March 1993 and is scheduled for completion in mid-1995. The initial scope for the project is the evaluation of those structures, systems, and components that are within the scope of the Rule. Because of the number of systems to be evaluated (∼50), the desired completion schedule, and cost considerations, a streamlined approach to PM optimization and documentation is being utilized

Advances in safety related maintenance

International Nuclear Information System (INIS)

2000-03-01

The maintenance of systems, structures and components in nuclear power plants (NPPs) plays an important role in assuring their safe and reliable operation. Worldwide, NPP maintenance managers are seeking to reduce overall maintenance costs while maintaining or improving the levels of safety and reliability. Thus, the issue of NPP maintenance is one of the most challenging aspects of nuclear power generation. There is a direct relation between safety and maintenance. While maintenance alone (apart from modifications) will not make a plant safer than its original design, deficient maintenance may result in either an increased number of transients and challenges to safety systems or reduced reliability and availability of safety systems. The confidence that NPP structures, systems and components will function as designed is ultimately based on programmes which monitor both their reliability and availability to perform their intended safety function. Because of this, approaches to monitor the effectiveness of maintenance are also necessary. An effective maintenance programme ensures that there is a balance between the improvement in component reliability to be achieved and the loss of component function due to maintenance downtime. This implies that the safety level of an NPP should not be adversely affected by maintenance performed during operation. The nuclear industry widely acknowledges the importance of maintenance in NPP safety and operation and therefore devotes great efforts to develop techniques, methods and tools to aid in maintenance planning, follow-up and optimization, and in assuring the effectiveness of maintenance

System Reliability Engineering

International Nuclear Information System (INIS)

Lim, Tae Jin

2005-02-01

This book tells of reliability engineering, which includes quality and reliability, reliability data, importance of reliability engineering, reliability and measure, the poisson process like goodness of fit test and the poisson arrival model, reliability estimation like exponential distribution, reliability of systems, availability, preventive maintenance such as replacement policies, minimal repair policy, shock models, spares, group maintenance and periodic inspection, analysis of common cause failure, and analysis model of repair effect.

A holistic framework of degradation modeling for reliability analysis and maintenance optimization of nuclear safety systems

International Nuclear Information System (INIS)

Lin, Yanhui

2016-01-01

Components of nuclear safety systems are in general highly reliable, which leads to a difficulty in modeling their degradation and failure behaviors due to the limited amount of data available. Besides, the complexity of such modeling task is increased by the fact that these systems are often subject to multiple competing degradation processes and that these can be dependent under certain circumstances, and influenced by a number of external factors (e.g. temperature, stress, mechanical shocks, etc.). In this complicated problem setting, this PhD work aims to develop a holistic framework of models and computational methods for the reliability-based analysis and maintenance optimization of nuclear safety systems taking into account the available knowledge on the systems, degradation and failure behaviors, their dependencies, the external influencing factors and the associated uncertainties.The original scientific contributions of the work are: (1) For single components, we integrate random shocks into multi-state physics models for component reliability analysis, considering general dependencies between the degradation and two types of random shocks. (2) For multi-component systems (with a limited number of components):(a) a piecewise-deterministic Markov process modeling framework is developed to treat degradation dependency in a system whose degradation processes are modeled by physics-based models and multi-state models; (b) epistemic uncertainty due to incomplete or imprecise knowledge is considered and a finite-volume scheme is extended to assess the (fuzzy) system reliability; (c) the mean absolute deviation importance measures are extended for components with multiple dependent competing degradation processes and subject to maintenance; (d) the optimal maintenance policy considering epistemic uncertainty and degradation dependency is derived by combining finite-volume scheme, differential evolution and non-dominated sorting differential evolution; (e) the

Achievement report for fiscal 1998. Research and development of a multi-plant maintenance system (the first year); 1998 nendo seika hokokusho. Odanteki maintenance gijutsu no kenkyu kaihatsu (dai 1 nendo)

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

This research and development is intended to structure a network centering around a center having systematized high-level maintenance technology, by utilizing the technological infrastructure having been built in local areas, together with element technologies possessed by national and private research institutes, universities and colleges. It is also purposed to establish a new industrial system for maintenance to realize high reliability, high operation rate and low cost in plants in certain areas. The present fiscal year had the following achievements: research and development of a maintenance system, a maintenance model, a maintenance vehicle, damage estimating technology for stationary parts such as piping, an anomaly diagnostic system using acoustic emission, an anomaly diagnostic system using wear particles in lubricant, an anti-wear material using surface modification, a lubrication control system, and an anomaly diagnostic system using ultrasonic waves. The research and development executing organization was divided into four groups for the maintenance system, maintenance model, maintenance vehicle, and maintenance tool. All groups have achieved the initial plans satisfactorily. (NEDO)

The maintenance training center of the paks nuclear power plant - past, present and future

International Nuclear Information System (INIS)

Kiss, I.

2001-01-01

The safety of the Paks nuclear power plant (Paks NPP) is a political-economic factor with general influence on the stability of the Hungarian economy. Since the beginning of the 1990s, the plant management has been taking significant efforts to learn about the factors that define plant safety and to reveal areas where safety can be further improved. Major emphasis is also placed on the provision of resources and creation of conditions necessary for the preservation of staff competence. In 1997 a separate, maintenance-specific facility was erected. The Maintenance Training Center of the Paks NPP is a worldwide major unique center. (orig.) [de

Reliability And Maintenance Analysis Of CCTV Systems Used In Rail Transport

Directory of Open Access Journals (Sweden)

Siergiejczyk Mirosław

2015-11-01

Full Text Available CCTV systems are widely used across plethora of industrial areas including transport, where their function is to support transport telematics systems. Among others, they are used to ensure travel safety. This paper presented a reliability and maintenance analysis of CCTV. It led to building a relationships graph and then Chapman–Kolmogorov system of equations was derived to describe it. Drawing on those equations, relationships for calculating probability of system staying in state of full ability SPZ, state of the impendency over safety SZB1 as well as state of unreliability of safety SB were derived.

Improving nuclear power plant reliability through predictive maintenance

International Nuclear Information System (INIS)

Geilhausen, R.; Kunze, U.

1996-01-01

Maintenance strategies can be assigned to one of three categories: failure maintenance, periodic maintenance or condition-oriented maintenance. The optimum maintenance scheme can be selected on the basis of a cost-benefit analysis but the safety of life and limb or the political climate for NPP can hardly expressed in numbers. The implementation of preventive maintenance needs two preconditions: high-performance instrumentation in the form of stationary and mobile monitoring systems for the determination of the condition of the nuclear power plant components and provision of a tool that can handle both the organization of the work and the evaluation of the results obtained. (authors)

Job analysis of the maintenance supervisor and instrument and control supervisor positions for the nuclear power plant maintenance personnel reliability model

International Nuclear Information System (INIS)

Bartter, W.D.; Siegel, A.I.; Federman, P.J.

1982-11-01

The present report presents the results of an analysis of the jobs of maintenance mechanic supervisors and instrument and control technician supervisors in nuclear power plants. Such an analysis was considered to be a necessary step in defining the scope and focus of a model for predicting and analyzing nuclear power maintenance reliability. The model will focus upon tasks and subtasks performed by various job positions. The results of this job analysis, along with the results of a survey of user needs vis-a-vis such a model and the results of parallel analyses of the job of maintenance mechanics and of instrument and control technicians provide the sound foundation on which such a model may be built. Job analysis possesses implications for a number of purposes. It provides insight into selection standards, job structuring and organization, performance analysis, training objective establishment, and training content derivation. Accordingly, the results of the present work possess implications for a variety of interest areas relative to safe and efficient operation of nuclear power plants

Component-Based Data-Driven Predictive Maintenance to Reduce Unscheduled Maintenance Events

NARCIS (Netherlands)

Verhagen, W.J.C.; Curran, R.; de Boer, L.W.M.; Chen, C.H.; Trappey, A.C.; Peruzzini, M.; Stjepandić, J.; Wognum, N.

2017-01-01

Costs associated with unscheduled and preventive maintenance can contribute significantly to an airline's expenditure. Reliability analysis can help to identify and plan for maintenance events. Reliability analysis in industry is often limited to statistically based

Probabilistic methods for maintenance program optimization

International Nuclear Information System (INIS)

Liming, J.K.; Smith, M.J.; Gekler, W.C.

1989-01-01

In today's regulatory and economic environments, it is more important than ever that managers, engineers, and plant staff join together in developing and implementing effective management plans for safety and economic risk. This need applied to both power generating stations and other process facilities. One of the most critical parts of these management plans is the development and continuous enhancement of a maintenance program that optimizes plant or facility safety and profitability. The ultimate objective is to maximize the potential for station or facility success, usually measured in terms of projected financial profitability, while meeting or exceeding meaningful and reasonable safety goals, usually measured in terms of projected damage or consequence frequencies. This paper describes the use of the latest concepts in developing and evaluating maintenance programs to achieve maintenance program optimization (MPO). These concepts are based on significant field experience gained through the integration and application of fundamentals developed for industry and Electric Power Research Institute (EPRI)-sponsored projects on preventive maintenance (PM) program development and reliability-centered maintenance (RCM)

A methodology based in particle swarm optimization algorithm for preventive maintenance focused in reliability and cost

International Nuclear Information System (INIS)

Luz, Andre Ferreira da

2009-01-01

In this work, a Particle Swarm Optimization Algorithm (PSO) is developed for preventive maintenance optimization. The proposed methodology, which allows the use flexible intervals between maintenance interventions, instead of considering fixed periods (as usual), allows a better adaptation of scheduling in order to deal with the failure rates of components under aging. Moreover, because of this flexibility, the planning of preventive maintenance becomes a difficult task. Motivated by the fact that the PSO has proved to be very competitive compared to other optimization tools, this work investigates the use of PSO as an alternative tool of optimization. Considering that PSO works in a real and continuous space, it is a challenge to use it for discrete optimization, in which scheduling may comprise variable number of maintenance interventions. The PSO model developed in this work overcome such difficulty. The proposed PSO searches for the best policy for maintaining and considers several aspects, such as: probability of needing repair (corrective maintenance), the cost of such repairs, typical outage times, costs of preventive maintenance, the impact of maintaining the reliability of systems as a whole, and the probability of imperfect maintenance. To evaluate the proposed methodology, we investigate an electro-mechanical system consisting of three pumps and four valves, High Pressure Injection System (HPIS) of a PWR. Results show that PSO is quite efficient in finding the optimum preventive maintenance policies for the HPIS. (author)

Equipment Maintenance management support system based on statistical analysis of maintenance history data

International Nuclear Information System (INIS)

Shimizu, S.; Ando, Y.; Morioka, T.

1990-01-01

Plant maintenance is recently becoming important with the increase in the number of nuclear power stations and in plant operating time. Various kinds of requirements for plant maintenance, such as countermeasures for equipment degradation and saving maintenance costs while keeping up plant reliability and productivity, are proposed. For this purpose, plant maintenance programs should be improved based on equipment reliability estimated by field data. In order to meet these requirements, it is planned to develop an equipment maintenance management support system for nuclear power plants based on statistical analysis of equipment maintenance history data. The large difference between this proposed new method and current similar methods is to evaluate not only failure data but maintenance data, which includes normal termination data and some degree of degradation or functional disorder data for equipment and parts. So, it is possible to utilize these field data for improving maintenance schedules and to evaluate actual equipment and parts reliability under the current maintenance schedule. In the present paper, the authors show the objectives of this system, an outline of this system and its functions, and the basic technique for collecting and managing of maintenance history data on statistical analysis. It is shown, from the results of feasibility tests using simulation data of maintenance history, that this system has the ability to provide useful information for maintenance and the design enhancement

Industrial Maintenance Strategies

International Nuclear Information System (INIS)

Sajjad Akbar

2006-01-01

Industrial plants have become more complex due to technological advancement. This has made the task of maintenance more difficult. The maintenance costs in terms of resources and downtime loss are so high that maintenance function has become a critical factor in a plant's profitability. Industry should devote as much forethought to the management of maintenance function as to production. Maintenance has grown from an art to a precise, technical engineering science. Planning, organizing scheduling and control of maintenance using modern techniques pays dividends in the form of reduced costs and increased reliability. The magnitude and the dimension of maintenance have multiplied due to development in the engineering technologies. Production cost and capacities are directly affected by the breakdown time. Total operating cost including the maintenance cost plays an important role in replacement dimension. The integrated system approach would bring forth the desired results of high maintenance standards. The standards once achieved and sustained, would add to the reliability of the plan and relieve heavy stresses and strains on the engineering logistic support. (author)

Development of advanced human-machine system for plant operation and maintenance

International Nuclear Information System (INIS)

Wu, Wei; Ohi, Tadashi; Yoshikawa, Hidekazu; Sawaragi, Tetsuo; Kitamura, Masaharu; Furuta, Kazuo; Gofuku, Akio; Ito, Koji

2004-01-01

With the worldwide deregulation of the power industry, and the aging of the nuclear power plants (NPPs), concerns are growing over the reliability and safety of the NPPs, because the regulation of man power may lower the current high level of reliability and safety. In this paper, a concept of overall integrated plant management mechanism is proposed, in order to meet the requirements of cutting costs of NPPs and the requirements of maintaining or increasing safety and reliability. The concept is called as satellite operation maintenance center (SOMC). SOMC integrates the operation and maintenance activities of several NPP units by utilizing advanced information technologies to support cooperation activities between workers allocated at SOMC and the field workers. As for the operation activities, a framework called as Advanced Operation System (AOS) is proposed in this paper. AOS consists of three support sub-systems: dynamic operation permission system(DyOPS), supervisor information presentation system using interface agent, and crew performance evaluation system. As for the maintenance activities, a framework called as Ubiquitous-Computing-based Maintenance support System (UCMS) is proposed next. Two case studies are described, in order to show the way of how UCMS support field workers to do maintenance tasks efficiently, safely, and infallibly as well. Finally, a prospect of SOMC is shown in order to explain the way of how the technology elements developed in this project could be integrated as a whole one system to support maintenance activities of NPPs in the future. (author)

The establish and application of equipment reliability database in Nuclear Power Plant

International Nuclear Information System (INIS)

Zheng Wei; Li He

2006-03-01

Take the case of Daya Bay Nuclear Power Plant, the collecting and handling of equipment reliability data, the calculation method of reliability parameters and the establish and application of reliability databases, etc. are discussed. The data source involved the design information of the equipment, the operation information, the maintenance information and periodically test record, etc. Equipment reliability database built on a base of the operation experience. It provided the valid tool for thoroughly and objectively recording the operation history and the present condition of various equipment of the plant; supervising the appearance of the equipment, especially the safety-related equipment, provided the very practical worth information for enhancing the safety and availability management of the equipment and insuring the safety and economic operation of the plant; and provided the essential data for the research and applications in safety management, reliability analysis, probabilistic safety assessment, reliability centered maintenance and economic management in nuclear power plant. (authors)

With a re-engineering of maintenance to a profitably oriented maintenance

International Nuclear Information System (INIS)

Angelevska, Silvana; Jolevski, Tome

2000-01-01

This paper presents an overview of effectiveness of the profit centered maintenance as a contemporary way of the maintenance management concept. Such redesign of a maintenance procedure results in significant gains in cost reduction and increase of the profitability and competitiveness of energy. The business process re engineering - a modern management control theory that is important aspect of the profit centered maintenance is summarized

Paranal maintenance and CMMS experience

Science.gov (United States)

Montano, Nelson

2004-10-01

During the last four years of operations, low technical downtime has been one of the relevant records of the Paranal Observatory. From the beginning of the Very Large Telescope (VLT) project, European Southern Observatory (ESO) has considered the implementation of a proper maintenance strategy a fundamental point in order to ensure low technical down time and preserve the Observatory's assets. The implementation of the maintenance strategy was based on the following aspects: - Strong maintenance sense during the design stage. Line Replacement Unit (LRU) concept, standardization and modularity of the Observatory equipment - Creation of a dedicated team for Maintenance - The implementation of a Computerized Maintenance Management System After four operational years, the result of these aspects has exceeded the expectations; the Observatory has been operating with high availability under a sustainable strategy. The strengths of the maintenance strategy have been based on modern maintenance concepts applied by regular production companies, where any minute of down time involves high cost. The operation of the actual Paranal Maintenance System is based mainly on proactive activities, such as regular inspections, preventive maintenance (PM) and predictive maintenance (PdM) plans. Nevertheless, it has been necessary to implement a strong plan for corrective maintenance (CM). The Spare Parts Strategy has also been an important point linked to the Maintenance Strategy and CMMS implementation. At present, almost 4,000 items related to the Observatory spare parts are loaded into the CMMS database. Currently, we are studying the implementation of a Reliability Centered Maintenance (RCM) project in one of our critical systems The following document presents the actual status of the Paranal Maintenance Strategy and which have been the motivations to implement the established strategy.

JRR-3 maintenance program utilizing accumulated maintenance data

International Nuclear Information System (INIS)

Izumo, Hironobu; Kato, Tomoaki; Kinase, Masami; Torii, Yoshiya; Murayama, Yoji

2007-07-01

JRR-3(Japan Research Reactor No.3) has been operated for more than 15 years after the modification, without significant troubles by carrying out maintenance such as the preventive maintenance (mainly time-based maintenance) for the safety-grade equipments and the breakdown maintenance for the non-safety-grade equipments. Unscheduled shutdowns causes by aged non-safety-grade equipments have been increasing, and the resources such as budgets have been decreasing year by year. In this situation, JRR-3 maintenance program was reviewed about safety, reliability and economic efficiency. This report offers the policy of the maintenance review and the future direction of maintenance programs. (author)

An approach to integrating surveillance and maintenance tasks to prevent the dominant failure causes of critical components

International Nuclear Information System (INIS)

Martorell, S.; Munoz, A.; Serradell, V.

1995-01-01

Surveillance requirements and maintenance activities in a nuclear power plant aim to preserve components' inherent reliability. Up to now, predictive and preventive maintenance mainly concerned plant staff, but the US Nuclear Regulatory Commission Maintenance Rule released in July 1991 will have significant impact on how nuclear power plants perform and document this maintenance. Reliability Centered Maintenance (RCM) is a systematic methodology to establish maintenance tasks for critical components in plant with a high degree of compliance with the goals of the Rule. RCM pursues the identification of applicable and efficient tasks to prevent these components from developing their dominant failure causes, and, in turn, towards achieving proper levels of components availability with low cost. In this paper, we present an approach for identifying the most suitable set of tasks to achieve this goal, which involves the integration of maintenance activities and surveillance requirements for each critical component based on the unavailability and cost associated with each individual task which is performed on it

Remote assembly and maintenance of fusion reactors

International Nuclear Information System (INIS)

Becquet, M.C.; Farfaletti-Casali, F.

1991-01-01

This paper intend to present the state of the art in the field of remote assembly and maintenance, including system analysis design and operation for controlled fusion device such as JET, and the next NET and ITER reactors. The operational constraints of fusion reactors with respect to temperature, radiations dose rates and cumulated doses are considered with the resulting design requirements. Concepts like articulated boom, in-vessel vehicle and blanket handling device are presented. The close relations between computer simulations and experimental validation of those concepts are emphasized to ensure reliability of the operational behavior. Mockups and prototypes in reduced and full scale, as operating machines are described to illustrate the progress in remote operations for fusion reactors. The developments achieved at the Institute for System Engineering and Informatics of the Joint Research Center, in the field of remote blanket maintenance, reliability assessment of RH systems and remote cut and welding of lips joints are considered. (author)

A genetic algorithm solution for a nuclear power plant risk-cost maintenance model

International Nuclear Information System (INIS)

Tong Jiejuan; Mao Dingyuan; Xue Dazhi

2004-01-01

Reliability Centered Maintenance (RCM) is one of the popular maintenance optimization methods according to certain kinds of priorities. Traditional RCM usually analyzes and optimizes the maintenance strategy from the viewpoint of component instead of the whole maintenance program impact. Research presented in this paper is a pilot study using PSA techniques in RCM. How to reflect the effect on component unavailability by the maintenance activities such as surveillance testing and preventive maintenance in PSA model is discussed firstly. Based on the discussion, a maintenance risk-cost model is established for global maintenance optimization in a nuclear power plant, and a genetic algorithm (GA) is applied to solve such a model to get the global optimized maintenance strategy. Finally, the result got from a simple test case based on a risk-cost model consisting of 10 components is presented

The maintenance optimization of structural components in nuclear power plants

International Nuclear Information System (INIS)

Bryla, P.; Ardorino, F.; Aufort, P.; Jacquot, J.P.; Magne, L.; Pitner, P.; Verite, B.; Villain, B.; Monnier, B.

1997-10-01

An optimization process, called 'OMF-Structures', is developed by Electricite de France (EDF) in order to extend the current 'OMF' Reliability Centered Maintenance to piping structural components. The Auxiliary Feedwater System of a 900 MW French nuclear plant has been studied in order to lay the foundations of the method. This paper presents the currently proposed principles of the process. The principles of the OMF-Structures process include 'Risk-Based Inspection' concepts within an RCM process. Two main phases are identified: The purpose of the first phase is to select the risk-significant failure modes and associated elements. This phase consists of two major steps: potential consequences evaluation and reliability performance evaluation. The second phase consists of the definition of preventive maintenance programs for piping elements that are associated with risk-significant failure modes. (author)

Education and training of operators and maintenance staff at Hamaoka Nuclear Power Stations

International Nuclear Information System (INIS)

Makido, Hideki; Hayashi, Haruhisa

1999-01-01

At Hamaoka Nuclear Power Station, in order to ensure higher safety and reliability of plant operation, education and training is provided consistently, on a comprehensive basis, for all operating, maintenance and other technical staff, aimed at developing more capable human resources in the nuclear power division. To this end, Hamaoka Nuclear Power Station has the 'Nuclear Training Center' on its site. The training center provides the technical personnel including operators and maintenance personnel with practical training, utilizing simulators for operation training and the identical facilities with those at the real plant. Thus, it plays a central role in promoting comprehensive education and training concerning nuclear power generation. Our education system covers knowledge and skills necessary for the safe and stable operation of nuclear power plant, targeting new employees to managerial personnel. It is also organized systematically in accordance with experience and job level. We will report the present education and training of operators and maintenance personnel at Hamaoka Nuclear Training Center. (author)

Development of a Reliability Program approach to assuring operational nuclear safety

International Nuclear Information System (INIS)

Mueller, C.J.; Bezella, W.A.

1985-01-01

A Reliability Program (RP) model based on proven reliability techniques used in other high technology industries is being formulated for potential application in the nuclear power industry. Research findings are discussed. The reliability methods employed under NASA and military direction, commercial airline and related FAA programs were surveyed with several reliability concepts (e.g., quantitative reliability goals, reliability centered maintenance) appearing to be directly transferable. Other tasks in the RP development effort involved the benchmarking and evaluation of the existing nuclear regulations and practices relevant to safety/reliability integration. A review of current risk-dominant issues was also conducted using results from existing probabilistic risk assessment studies. The ongoing RP development tasks have concentrated on defining a RP for the operating phase of a nuclear plant's lifecycle. The RP approach incorporates safety systems risk/reliability analysis and performance monitoring activities with dedicated tasks that integrate these activities with operating, surveillance, and maintenance of the plant. The detection, root-cause evaluation and before-the-fact correction of incipient or actual systems failures as a mechanism for maintaining plant safety is a major objective of the RP

Evaluation of reliability of on-site A.C. power systems based on maintenance records

Energy Technology Data Exchange (ETDEWEB)

Basso, G.; Pia, S. [ENEA/TERM/VAOEC, C.R.E. Casaccla via Anguillarese, 00100 Roma/Rome (Italy); Fusari, W. [ENEL, Rome (Italy); Soressi, G.; Vaccari, G. [ENEL, Centro di Ricerca Termica e Nucl., Via Rubattino, 54, 1-20134 Mllano/Milan (Italy)

1986-02-15

To the end of ascertain in what extent the evaluation of reliability of emergency diesel generators (D.G.) can be improved by means of a deeper knowledge of their operating history a study has been carried-out on 21 D.G. sets: 4 D.G. of the Caorso nuclear plant (BWR, 870 MWe) and 17 D.G. in service at 6 steam-electric fossil-fuelled plants. The major points of interest resulting from this study are: 1) reliability assessments of A.C. on-site power Systems, made on the basis of outcomes of surveillance tests, may lead to results which overestimate the real performance. 2) the unreliability of a redundant System of stand-by components is determined in large extent by unavailabilities due to scheduled and unscheduled maintenance, latent failures, tests. (authors)

Evaluation of reliability of on-site A.C. power systems based on maintenance records

International Nuclear Information System (INIS)

Basso, G.; Pia, S.; Fusari, W.; Soressi, G.; Vaccari, G.

1986-01-01

To the end of ascertain in what extent the evaluation of reliability of emergency diesel generators (D.G.) can be improved by means of a deeper knowledge of their operating history a study has been carried-out on 21 D.G. sets: 4 D.G. of the Caorso nuclear plant (BWR, 870 MWe) and 17 D.G. in service at 6 steam-electric fossil-fuelled plants. The major points of interest resulting from this study are: 1) reliability assessments of A.C. on-site power Systems, made on the basis of outcomes of surveillance tests, may lead to results which overestimate the real performance. 2) the unreliability of a redundant System of stand-by components is determined in large extent by unavailabilities due to scheduled and unscheduled maintenance, latent failures, tests. (authors)

A comprehensive approach to RCM-based preventive maintenance program development

International Nuclear Information System (INIS)

Hall, B.E.; Davis, T.; Pennington, A.J.

1988-01-01

In late 1986, Public Service Electric and Gas Company (PSE ampersand G) concluded that to support its vision and strategic planning it would be necessary to develop a consistent approach to maintenance for all nuclear units at the artificial island. General Physics Corporation was selected to lead a consultant team to support full-scale development of a preventive maintenance (PM) program for Salem and Hope Creek generating stations based on a reliability-centered maintenance (RCM) approach. RCM was selected because it represents a systematic approach to developing a PM program that provides a logical, consistent, and traceable methodology and produces a well-documented engineering basis for the program. Early in 1987, primary objectives for the PM program were defined. The Phase I tasks addressed key programmatic areas such as maintenance philosophy, procedures, condition monitoring, performance trending, equipment failure data base, ogranization, PM program effectiveness evaluation, RCM process, reliability/availability modeling, information management, training, spare parts, software/hardware, and commitments. Phase I of the PM program development project was completed in January 1988. Highlights of the Phase I work and the PM program manual are described

Application of Bayesian statistical decision theory for a maintenance optimization problem

International Nuclear Information System (INIS)

Procaccia, H.; Cordier, R.; Muller, S.

1997-01-01

Reliability-centered maintenance (RCM) is a rational approach that can be used to identify the equipment of facilities that may turn out to be critical with respect to safety, to availability, or to maintenance costs. Is is dor these critical pieces of equipment alone that a corrective (one waits for a failure) or preventive (the type and frequency are specified) maintenance policy is established. But this approach has limitations: - when there is little operating feedback and it concerns rare events affecting a piece of equipment judged critical on a priori grounds (how is it possible, in this case, to decide whether or not it is critical, since there is conflict between the gravity of the potential failure and its frequency?); - when the aim is propose an optimal maintenance frequency for a critical piece of equipment - changing the maintenance frequency hitherto applied may cause a significant drift in the observed reliability of the equipment, an aspect not generally taken into account in the RCM approach. In these two situations, expert judgments can be combined with the available operating feedback (Bayesian approach) and the combination of risk of failure and economic consequences taken into account (statistical decision theory) to achieve a true optimization of maintenance policy choices. This paper presents an application on the maintenance of diesel generator component

Practical application of reliability engineering in detailed design and maintenance

International Nuclear Information System (INIS)

Barden, S.E.

1975-01-01

Modern plant systems are closely coupled combinations of sophisticated and expensive equipment, some important parts of which may be in the development stage (high technology sector), and simpler, crude but not necessarily cheap equipment (low technology sector). Manpower resources involved with such plant systems can also be placed in high and low technology categories (i.e. specialist design and construction staff, and production staff, respectively). Neither can operate effectively without the other, and both are equally important. A sophisticated on-line computer controlling plant or analysing fault symptoms is useless, if not unsafe, if the peripheral sensing and control equipment on plant providing input data is poorly designed and inaccurate, and/or unreliable because of inadequate maintenance. Similarly, the designer can be misled and misinformed, and subsequent design evolution can be wrongly directed, if production recors do not accurately reflect what is actually happening on the plant. The application of Reliability Technology can be counter productive if it demands more effort in the collection of data that it save in facilitating quick, correct engineering decisions, and more accurate assessments of resource requirements. Reliability Engineering techniques must be simplified to made their use widely adopted in the important low technology sector, and established in all financial and contractural procedures associated with design specification and production management. This paper develops this theme with practical examples. (author)

Evaluation of Sociodemographic Determinants in Narcotic Users Referring to Center for Methadone Maintenance Therapy of Yazd, Iran

Directory of Open Access Journals (Sweden)

M.H. Lotfi

2012-07-01

Full Text Available Introduction: Addiction is a habit or behavior that is often hard to quit. It is estimated that 190 million persons are substance users around the world. Substance abuse creates tolerance after a while. Shortly after taking the drug, a person will not enjoy as the beginning of its use; that is why the amount of substance used is gradually increased. The purpose of this study was to find the reasons of tendency to narcotics among addicted individuals referred to methadone maintenance therapy (MMT center in Yazd. Materials & Methods: This study was a descriptive-analytic study on 100 addicts referred to methadone maintenance treatment center (MMT in Yazd. Data was collected by a pre-designed questionnaire with acceptable validity and reliability. Data was analyzed using SPSS statistical software and employing descriptive statistics such as percentage, ratio, mean, standard deviation and statistical tests such as t-test and chi- square was performed. Results: 41.9 % of addicts were unemployed, 4.77% married and 5.64% had elementary education. The most common method of substance consumption was inhalation (2.40%. Heroin was the most frequent type of substance used (1/51% The relationship between marital status and type of substance used, and age of onset of drug use was significant. The frequency of substance consumption was significantly different regarding the history of drug use in father, brother and spouses of patients in both sexes. Conclusion: Results of the current study showed that subjects at an early age (adolescence and early adulthood, individuals with low educational status, those with unstable jobs and low income, presence of addicted individuals among first-degree relatives can be the causes leading to addiction in the community.

Regulatory surveillance of safety related maintenance at nuclear power plants. Report of a technical committee meeting

International Nuclear Information System (INIS)

1997-08-01

The operational safety and reliability of a nuclear power plant as well as its availability for electricity generation depend on, among other things, its maintenance programme. Regulatory bodies therefore have considerable interest in maintenance activities. There are several approaches to maintenance, i.e. reliability centered maintenance or risk focused maintenance, aimed at optimizing maintenance by focusing on important components or systems. These approaches may result in significant changes to maintenance activities and therefore have to be considered for regulatory acceptance. In order to review and discuss the status of maintenance regulation in participating countries, the IAEA convened a Technical Committee Meeting on Regulatory Oversight of Maintenance Activities at Nuclear Power Plants in Vienna from 9 to 13 October 1995. The meeting was attended by 16 experts from 11 countries. In addition to the consideration of papers that were presented and which are reproduced here, extensive group and panel discussions took place during the meeting. These covered three main topics: general features and basic characteristics of maintenance regulation, regulatory acceptance of maintenance optimization and use of PSA for maintenance optimization. The discussion are summarized in Section 2. Section 3 discusses the following three additional topics: regulatory involvement in the maintenance programme, modifications to the maintenance programme and personnel related aspects of maintenance. The conclusions are presented in Section 4. Figs, tabs

Preventative Maintenance.

Science.gov (United States)

Migliorino, James

Boards of education must be convinced that spending money up front for preventive maintenance will, in the long run, save districts' tax dollars. A good program of preventive maintenance can minimize disruption of service; reduce repair costs, energy consumption, and overtime; improve labor productivity and system equipment reliability; handle…

Preventive maintenance: optimization of time - based discard decisions at the bruce nuclear generating station

International Nuclear Information System (INIS)

Doyle, E.K.; Jardine, A.K.S.

2001-01-01

The use of various maintenance optimization techniques at Bruce has lead to cost effective preventive maintenance applications for complex systems. As previously reported at ICONE 6 in New Orleans, 1996, several innovative practices reduced Reliability Centered Maintenance costs while maintaining the accuracy of the analysis. The optimization strategy has undergone further evolution and at the present an Integrated Maintenance Program (IMP) is in place where an Expert Panel consisting of all players/experts proceed through each system in a disciplined fashion and reach agreement on all items under a rigorous time frame. It is well known that there are essentially 3 maintenance based actions that can flow from a Maintenance Optimization Analysis: condition based maintenance, time based maintenance and time based discard. The present effort deals with time based discard decisions. Maintenance data from the Remote On-Power Fuel Changing System was used. (author)

On preventive maintenance policy of a critical reliability level for system subject to degradation

International Nuclear Information System (INIS)

Zhao, Y.X.

2003-01-01

Conventional preventive maintenance (PM) policies generally hold same time interval for PM actions and are often applied with known failure modes. The same time interval will give unavoidably decreasing reliabilities at the PM actions for degradation system with imperfect PM effect and the known failure modes may be inaccurate in practice. Therefore, field managers would prefer policy with an acceptable reliability level to keep system often at a good state. A PM policy with the critical reliability level is presented to address the preference of field managers. Through assuming that system after a PM action starts a new failure process, a parameter so-called degradation ratio is introduced to represent the imperfect effect. The policy holds a law that there is same number of failures in the time intervals of various PM cycles, and same degradation ratio for the system reliability or benefit parameters such as the optimal time intervals and the hazard rates between the neighboring PM cycles. This law is valid to any of the failure modes that could be appropriately referred as a 'general isodegrading model', and the degradation ratio as a 'general isodegrading ratio'. In addition, life cycle availability and cost functions are derived for system with the policy. An analysis of the field data of a loading and unloading machine indicates that the reliability, availability and cost in life cycle might be well modeled by the present theory and approach

Lean Maintenance Applied to Improve Maintenance Efficiency in Thermoelectric Power Plants

OpenAIRE

Orlando Duran; Andrea Capaldo; Paulo Andrés Duran Acevedo

2017-01-01

Thermoelectric power plants consist of a set of critical equipment that require high levels of availability and reliability. Due to this, maintenance of these physical assets is gaining momentum in industry. Maintenance is considered as an activity that contributes to improving the availability, efficiency and productivity of each piece of equipment. Several techniques have been used to achieve greater efficiencies in maintenance, among which we can find the lean maintenance philosophy. Despi...

Applying Systems Engineering to Improve the Main Gas Turbine Exhaust System Maintenance Strategy for the CG-47 Ticonderoga Class Cruiser

Science.gov (United States)

2015-09-01

national security and prosperity (U.S. Navy 2014). In perspective, oceans are the lifeblood of the planet and its entire population . The National...maintenance strategy, reliability-centered maintenance, cost, schedule, performance, growth -work, new-work, optimal fleet response plan, time-directed...76 5. Main Gas Turbine Exhaust System Growth -Work ..................77 E. RECOMMENDATIONS TO IMPROVE THE MAIN GAS TURBINE EXHAUST SYSTEM

A Reliable, Non-Invasive Approach to Data Center Monitoring and Management

Directory of Open Access Journals (Sweden)

Moises Levy

2017-08-01

Full Text Available Recent standards, legislation, and best practices point to data center infrastructure management systems to control and monitor data center performance. This work presents an innovative approach to address some of the challenges that currently hinder data center management. It explains how monitoring and management systems should be envisioned and implemented. Key parameters associated with data center infrastructure and information technology equipment can be monitored in real-time across an entire facility using low-cost, low-power wireless sensors. Given the data centers’ mission critical nature, the system must be reliable and deployable through a non-invasive process. The need for the monitoring system is also presented through a feedback control systems perspective, which allows higher levels of automation. The data center monitoring and management system enables data gathering, analysis, and decision-making to improve performance, and to enhance asset utilization.

Reliability of the grid as function of power flow and configuration during maintenance

International Nuclear Information System (INIS)

Kovacs, Z.; Hlavac, P.; Janicek, F.

2012-01-01

The paper describes using of PSA (Probabilistic Safety Assessment) for analysis of the partial and total blackout of the grid for different power flows and configuration of the grid given by the preventive maintenance activities. The method uses event and fault tree analysis in combination with the dynamic stability analysis of the grid. The event trees model the grid response to the initiating event of the accident. The fault trees are used to model the reliability of the substation protection systems. Different end states of the event trees are simulated on the basis of dynamic stability analysis, as safe and emergency state, partial and total blackout. Minimal cut sets are generated, importance measures (Fussel-Vesely importance, risk increase factor and risk decrease factors) are calculated for the total and partial blackout. The most dominant initiating events and component failures are identified from the risk point of view. Using the PSA the model, of the transmission grid is being developed. The model can be implemented into the risk monitor software to analyze the risk for different configurations of the grid and to support the operation and the maintenance activities. (Authors)

Reliability Modeling of Wind Turbines

DEFF Research Database (Denmark)

Kostandyan, Erik

Cost reductions for offshore wind turbines are a substantial requirement in order to make offshore wind energy more competitive compared to other energy supply methods. During the 20 – 25 years of wind turbines useful life, Operation & Maintenance costs are typically estimated to be a quarter...... for Operation & Maintenance planning. Concentrating efforts on development of such models, this research is focused on reliability modeling of Wind Turbine critical subsystems (especially the power converter system). For reliability assessment of these components, structural reliability methods are applied...... to one third of the total cost of energy. Reduction of Operation & Maintenance costs will result in significant cost savings and result in cheaper electricity production. Operation & Maintenance processes mainly involve actions related to replacements or repair. Identifying the right times when...

Improving motor reliability in nuclear power plants: Volume 1, Performance evaluation and maintenance practices

International Nuclear Information System (INIS)

Subudhi, M.; Gunther, W.E.; Taylor, J.H.; Sugarman, A.C.; Sheets, M.W.

1987-11-01

This report constitutes the first of the three volumes under this NUREG. The report presents recommendations for developing a cost-effective program for performance evaluation and maintenance of electric motors in nuclear power plants. These recommendations are based on current industry practices, available techniques for monitoring degradation in motor components, manufacturer's recommendations, operating experience, and results from two laboratory tests on aged motors. Two laboratory test reports on a small and a large motor are presented in separate volumes of this NUREG. These provide the basis for the various functional indicators recommended for maintenance programs in this report. The overall preventive maintenance program is separated into two broad areas of activity aimed at mitigating the potential effects of equipment aging: Performance Evaluation and Equipment Maintenance. The latter involves actually maintaining the condition of the equipment while the former involves those activities undertaken to monitor degradation due to aging. These monitoring methods are further categorized into periodic testing, surveillance testing, continuous monitoring and inspections. This study focuses on the methods and procedures for performing the above activities to maintain the motors operationally ready in a nuclear facility. This includes an assessment of various functional indicators to determine their suitability for trending to monitor motor component condition. The intrusiveness of test methods and the present state-of-the-art for using the test equipment in a plant environment are discussed. In conclusion, implementation of the information provided in this report, will improve motor reliability in nuclear power plants. The study indicates the kinds of tests to conduct, how and when to conduct them, and to which motors the tests should be applied. 44 refs., 12 figs., 13 tabs

Efficiency evaluation of an electronic equipment: availability,reliability and maintenance; Notion d'efficacite d'un equipement electronique: disponibilite, fiabilite et maintenabilite

Energy Technology Data Exchange (ETDEWEB)

Guyot, C

1966-07-01

This concept of efficiency often called ''system effectiveness'', is presented and analyzed in terms of reliability and maintenance. It allows to define the availability factor of an electronic equipment. A procedure of evaluation is proposed. (A.L.B.)

Automated System Checkout to Support Predictive Maintenance for the Reusable Launch Vehicle

Science.gov (United States)

Patterson-Hine, Ann; Deb, Somnath; Kulkarni, Deepak; Wang, Yao; Lau, Sonie (Technical Monitor)

1998-01-01

The Propulsion Checkout and Control System (PCCS) is a predictive maintenance software system. The real-time checkout procedures and diagnostics are designed to detect components that need maintenance based on their condition, rather than using more conventional approaches such as scheduled or reliability centered maintenance. Predictive maintenance can reduce turn-around time and cost and increase safety as compared to conventional maintenance approaches. Real-time sensor validation, limit checking, statistical anomaly detection, and failure prediction based on simulation models are employed. Multi-signal models, useful for testability analysis during system design, are used during the operational phase to detect and isolate degraded or failed components. The TEAMS-RT real-time diagnostic engine was developed to utilize the multi-signal models by Qualtech Systems, Inc. Capability of predicting the maintenance condition was successfully demonstrated with a variety of data, from simulation to actual operation on the Integrated Propulsion Technology Demonstrator (IPTD) at Marshall Space Flight Center (MSFC). Playback of IPTD valve actuations for feature recognition updates identified an otherwise undetectable Main Propulsion System 12 inch prevalve degradation. The algorithms were loaded into the Propulsion Checkout and Control System for further development and are the first known application of predictive Integrated Vehicle Health Management to an operational cryogenic testbed. The software performed successfully in real-time, meeting the required performance goal of 1 second cycle time.

Optimal maintenance of a multi-unit system under dependencies

Science.gov (United States)

Sung, Ho-Joon

same end-goals as Reliability Centered Maintenance (RCM). RCM was first introduced to the aircraft industry in an attempt to bridge the gap between the empirically-driven and theory-driven approaches to establishing optimal maintenance policies. Under RCM, qualitative processes that enable the prioritizing of functions based on the criticality and influence would be combined with mathematical modeling to obtain the optimal maintenance policies. Where this thesis work deviates from RCM is its proposal to directly apply quantitative processes to model the reliability measures in optimal maintenance problem. First, Monte Carlo (MC) simulation, in conjunction with a pre-determined Design of Experiments (DOE) table, can be used as a numerical means of obtaining the corresponding discrete simulated outcomes of the reliability measures based on the combination of decision variables (e.g., periodic preventive maintenance interval, trigger age for opportunistic maintenance, etc.). These discrete simulation results can then be regressed as Response Surface Equations (RSEs) with respect to the decision variables. Such an approach to represent the reliability measures with continuous surrogate functions (i.e., the RSEs) not only enables the application of the numerical optimization technique to solve for optimal maintenance policies, but also obviates the need to make mathematical assumptions or impose over-simplifications on the structure of a multi-unit system for the sake of mathematical tractability. The applicability of the proposed methodology to a real-world optimal maintenance problem is showcased through its application to a Time Limited Dispatch (TLD) of Full Authority Digital Engine Control (FADEC) system. In broader terms, this proof-of-concept exercise can be described as a constrained optimization problem, whose objective is to identify the optimal system inspection interval that guarantees a certain level of availability for a multi-unit system. A variety of

Dukovany NPP maintenance management

International Nuclear Information System (INIS)

Siegel, F.

2005-01-01

Maintenance planning and management for the technological equipment of the Dukovany NPP are described. A Maintenance Control and Evaluation System has been developed and is in use to help manage the complex maintenance issue. Practical examples of outputs of the System, with a comprehensive use of the cost, reliability and safety related data, are presented. (author)

Research on operation and maintenance support system adaptive to human recognition and understanding in human-centered plant

International Nuclear Information System (INIS)

Numano, Masayoshi; Matsuoka, Takeshi; Mitomo, N.

2004-01-01

As a human-centered plant, advanced nuclear power plant needs appropriate role sharing between human and mobile intelligent agents. Human-machine cooperation for plant operation and maintenance activities is also required with an advanced interface. Plant's maintenance is programmed using mobile robots working under the radiation environments instead of human beings. Operation and maintenance support system adaptive to human recognition and understanding should be developed to establish adequate human and machine interface so as to induce human capabilities to the full and enable human to take responsibility for plan's operation. Plant's operation and maintenance can be cooperative activities between human and intelligent automonous agents having surveillance and control functions. Infrastructure of multi-agent simulation system for the support system has been investigated and developed based on work plans derived from the scheduler. (T. Tanaka)

20 CFR 670.220 - Are we responsible for the protection and maintenance of center facilities?

Science.gov (United States)

2010-04-01

... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Are we responsible for the protection and maintenance of center facilities? 670.220 Section 670.220 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR THE JOB CORPS UNDER TITLE I OF THE WORKFORCE INVESTMENT ACT Site Selection...

Reliability of software

International Nuclear Information System (INIS)

Kopetz, H.

1980-01-01

Common factors and differences in the reliability of hardware and software; reliability increase by means of methods of software redundancy. Maintenance of software for long term operating behavior. (HP) [de

Knowledge based maintenance

Energy Technology Data Exchange (ETDEWEB)

Sturm, A [Hamburgische Electacitaets-Werke AG Hamburg (Germany)

1998-12-31

The establishment of maintenance strategies is of crucial significance for the reliability of a plant and the economic efficiency of maintenance measures. Knowledge about the condition of components and plants from the technical and business management point of view therefore becomes one of the fundamental questions and the key to efficient management and maintenance. A new way to determine the maintenance strategy can be called: Knowledge Based Maintenance. A simple method for determining strategies while taking the technical condition of the components of the production process into account to the greatest possible degree which can be shown. A software with an algorithm for Knowledge Based Maintenance leads the user during complex work to the determination of maintenance strategies for this complex plant components. (orig.)

Knowledge based maintenance

Energy Technology Data Exchange (ETDEWEB)

Sturm, A. [Hamburgische Electacitaets-Werke AG Hamburg (Germany)

1997-12-31

The establishment of maintenance strategies is of crucial significance for the reliability of a plant and the economic efficiency of maintenance measures. Knowledge about the condition of components and plants from the technical and business management point of view therefore becomes one of the fundamental questions and the key to efficient management and maintenance. A new way to determine the maintenance strategy can be called: Knowledge Based Maintenance. A simple method for determining strategies while taking the technical condition of the components of the production process into account to the greatest possible degree which can be shown. A software with an algorithm for Knowledge Based Maintenance leads the user during complex work to the determination of maintenance strategies for this complex plant components. (orig.)

Maintenance contract strategies for reliability at minimum cost

International Nuclear Information System (INIS)

Gamman, E.

1992-01-01

The conference paper deals with offshore contract philosophies concerning maintenance. The main philosophies of the contract should be built on the following key success factors: Safe operations and correct quality must be sustained at any time; the maintenance contractor should be viewed as a cooperation partner, not only as a supplier; optimum exploitation of learning curve effects and economies of scale. The paper illustrates the importance of each of them in a contract context with a few recommendations

Human-centered automation of testing, surveillance and maintenance

International Nuclear Information System (INIS)

Bhatt, S.C.; Sun, B.K.H.

1991-01-01

Manual surveillance and testing of instrumentation, control and protection systems at nuclear power plants involves system and human errors which can lead to substantial plant down time. Frequent manual testing can also contribute significantly to operation and maintenance cost. Automation technology offers potential for prudent applications at the power plant to reduce testing errors and cost. To help address the testing problems and to harness the benefit of automation application, input from utilities is obtained on suitable automation approaches. This paper includes lessens from successful past experience at a few plants where some island of automation exist. The results are summarized as a set of specifications for semi automatic testing. A human-centered automation methodology is proposed with the guidelines for optimal human/computer division of tasks given. Implementation obstacles for significant changes of testing practices are identified and methods acceptable to nuclear power plants for addressing these obstacles have been suggested

9th International conference on CANDU maintenance

International Nuclear Information System (INIS)

2011-01-01

The 9th International Conference on CANDU Maintenance was held in Toronto, Ontario, Canada on December 4-6, 2011. The conference focused on Nuclear plant reliability and maintenance. Equipment reliability is a critical factor in achieving safe and reliable Nuclear Power Plant operations for many reasons. For one it reduces the challenges upon the operating staff and allows station personnel to 'go on the offence' instead of having to play defense in a reactive mode. Plant reliability ensures that there is time to study the issues in detail and develop solutions for long-term success. Let us not forget that the owner carries the burden of demonstrating the return on investment, and plant reliability goes a long way in helping to make the case for plant life extension. A good reputation for plant reliability provides the public capital necessary to build confidence and facilitate the licensing process. The proceedings papers and presentations given at the 9th International Conference on Candu Maintenance covered topics that include: Managing Worker; Radiation Dose; Full Life Cycle Management; Managing Maintenance Refurbishment; Designing for Maintainability; Inspection Techniques; and, Mitigating Degradation.

Design reliability engineering

International Nuclear Information System (INIS)

Buden, D.; Hunt, R.N.M.

1989-01-01

Improved design techniques are needed to achieve high reliability at minimum cost. This is especially true of space systems where lifetimes of many years without maintenance are needed and severe mass limitations exist. Reliability must be designed into these systems from the start. Techniques are now being explored to structure a formal design process that will be more complete and less expensive. The intent is to integrate the best features of design, reliability analysis, and expert systems to design highly reliable systems to meet stressing needs. Taken into account are the large uncertainties that exist in materials, design models, and fabrication techniques. Expert systems are a convenient method to integrate into the design process a complete definition of all elements that should be considered and an opportunity to integrate the design process with reliability, safety, test engineering, maintenance and operator training. 1 fig

Modern electronic maintenance principles

CERN Document Server

Garland, DJ

2013-01-01

Modern Electronic Maintenance Principles reviews the principles of maintaining modern, complex electronic equipment, with emphasis on preventive and corrective maintenance. Unfamiliar subjects such as the half-split method of fault location, functional diagrams, and fault finding guides are explained. This book consists of 12 chapters and begins by stressing the need for maintenance principles and discussing the problem of complexity as well as the requirements for a maintenance technician. The next chapter deals with the connection between reliability and maintenance and defines the terms fai

Technology Trend in the Maintenance of Nuclear Power Plants

International Nuclear Information System (INIS)

Yoon, Kyungsup; Lee, Unjang

2014-01-01

In this paper, overall technology evolution is reviewed and the improvements in the plant safety, reliability and productivity are described. And the issue and some recommendation for better maintenance of Korean nuclear power plants are presented as the interim study results on the 'Management and Regulatory Policy for the Nuclear Power Plant Maintenance and Equipment Reliability' under the agreement with the Nuclear Safety and Security Commission. The future trend in the maintenance technologies is also covered. Maintenance is the essential element for the enhancement of plant safety, reliability and economics and also for public safety. Therefore the regulator's involvements and the utility's active participation is inevitable for the better maintenance. For the better sustainability of our nuclear power plants the followings are recommended. ·Establishment of the good maintenance program and continuous improvement. ·Application of OLM on the safety related and non-safety related components by step-by-step approach. ·Improvement PRA technology for the accurate and reliable risk analysis. ·Continuous training and cultivation for the qualified maintenance personnel

Technology Trend in the Maintenance of Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Yoon, Kyungsup; Lee, Unjang [CTO and CEO, Seoul (Korea, Republic of)

2014-05-15

In this paper, overall technology evolution is reviewed and the improvements in the plant safety, reliability and productivity are described. And the issue and some recommendation for better maintenance of Korean nuclear power plants are presented as the interim study results on the 'Management and Regulatory Policy for the Nuclear Power Plant Maintenance and Equipment Reliability' under the agreement with the Nuclear Safety and Security Commission. The future trend in the maintenance technologies is also covered. Maintenance is the essential element for the enhancement of plant safety, reliability and economics and also for public safety. Therefore the regulator's involvements and the utility's active participation is inevitable for the better maintenance. For the better sustainability of our nuclear power plants the followings are recommended. ·Establishment of the good maintenance program and continuous improvement. ·Application of OLM on the safety related and non-safety related components by step-by-step approach. ·Improvement PRA technology for the accurate and reliable risk analysis. ·Continuous training and cultivation for the qualified maintenance personnel.

Overview of maintenance principles and regulatory supervision of maintenance activities at nuclear power plants in Slovakia

International Nuclear Information System (INIS)

Rohar, S.; Cepcek, S.

1997-01-01

The maintenance represents one of the most important tools to ensure safe and reliable operation of nuclear power plants. The emphasis of Nuclear Regulatory Authority of the Slovak Republic to the maintenance issue is expressed by requirements in the regulations. The current practice of maintenance management in operated nuclear power plants in Slovak Republic is presented. Main aspects of maintenance, as maintenance programme, organization of maintenance, responsibilities for maintenance are described. Activities of nuclear regulatory authority in maintenance process are presented too. (author)

Weibull distribution in reliability data analysis in nuclear power plant

International Nuclear Information System (INIS)

Ma Yingfei; Zhang Zhijian; Zhang Min; Zheng Gangyang

2015-01-01

Reliability is an important issue affecting each stage of the life cycle ranging from birth to death of a product or a system. The reliability engineering includes the equipment failure data processing, quantitative assessment of system reliability and maintenance, etc. Reliability data refers to the variety of data that describe the reliability of system or component during its operation. These data may be in the form of numbers, graphics, symbols, texts and curves. Quantitative reliability assessment is the task of the reliability data analysis. It provides the information related to preventing, detect, and correct the defects of the reliability design. Reliability data analysis under proceed with the various stages of product life cycle and reliability activities. Reliability data of Systems Structures and Components (SSCs) in Nuclear Power Plants is the key factor of probabilistic safety assessment (PSA); reliability centered maintenance and life cycle management. The Weibull distribution is widely used in reliability engineering, failure analysis, industrial engineering to represent manufacturing and delivery times. It is commonly used to model time to fail, time to repair and material strength. In this paper, an improved Weibull distribution is introduced to analyze the reliability data of the SSCs in Nuclear Power Plants. An example is given in the paper to present the result of the new method. The Weibull distribution of mechanical equipment for reliability data fitting ability is very strong in nuclear power plant. It's a widely used mathematical model for reliability analysis. The current commonly used methods are two-parameter and three-parameter Weibull distribution. Through comparison and analysis, the three-parameter Weibull distribution fits the data better. It can reflect the reliability characteristics of the equipment and it is more realistic to the actual situation. (author)

A Study on User-Centered Approach to Design an Augmented Reality Maintenance Support System in Nuclear Power Plant

International Nuclear Information System (INIS)

Koo, Jwa Jin; Seong, Poong Hyun

2007-01-01

In nuclear power plants (NPPs), as the plants become more reliable and complex, their inspection, maintenance and repair become increasingly challenging problems, and this requires many well experienced and well trained maintenance crew. On the other hands, reduction of life cycle costs of the plants is strongly required, and many crews are required to take charge of various kinds of devices, including their unfamiliar ones. Their task must be done under the strong time pressure of rigid maintenance schedule. This may cause human errors even by even the well experienced crews. Maintenance processes are both very important to guarantee quality for safety and often quite cumbersome. In the case of nuclear power plants, such processes usually demand access to documentation such as technical manuals, either in traditional paper form or electronic form. This is especially important where and when the procedures are performed infrequently. These considerations lead to considering Augmented Reality (AR) systems as an alternative to paper-based systems

Probabilistic approach to rationalization of plants maintenance

International Nuclear Information System (INIS)

Kasai, Masao; Notoya, Junichi; Uchimoto, Tetsuya; Miya, Kenzo

2001-01-01

Since there are a lot of equipments in large plants, their safety and reliability cannot be kept as high level as designed without maintenance activities. Then preventive maintenance is intensively executed in some large plants. However, it will be inefficient to perform the preventive maintenance blindly. To make maintenance activities effective, it is essential to identify the critical equipments influencing plant safety and/or reliability and carry out the maintenance by focusing attentions on these equipments. It needs quantitative analyses to identify the critical equipments based on the data of failure rates. However, complete data set of failure rates cannot necessarily be available for some plants such as nuclear power plants. In this study, we carry out the reliability analysis for generic LNG plant and calculate various quantitative risk importance measures for each equipment. We propose rather qualitative representations for some quantitative measures, considering the situation without complete data set and conclude that it is possible to rationalize maintenance procedure by using these rather qualitative measures, though the level of rationalization is of course limited. (author)

Reliability in automotive and mechanical engineering determination of component and system reliability

CERN Document Server

Bertsche, Bernd

2008-01-01

In the present contemporary climate of global competition in every branch of engineering and manufacture it has been shown from extensive customer surveys that above every other attribute, reliability stands as the most desired feature in a finished product. To survive this relentless fight for survival any organisation, which neglect the plea of attaining to excellence in reliability, will do so at a serious cost Reliability in Automotive and Mechanical Engineering draws together a wide spectrum of diverse and relevant applications and analyses on reliability engineering. This is distilled into this attractive and well documented volume and practising engineers are challenged with the formidable task of simultaneously improving reliability and reducing the costs and down-time due to maintenance. The volume brings together eleven chapters to highlight the importance of the interrelated reliability and maintenance disciplines. They represent the development trends and progress resulting in making this book ess...

Opportunities and supporting activities to promote preventive maintenance of NPPs in Japan

International Nuclear Information System (INIS)

Sanada, A.; Shinkawa, T.; Sakurada, M.

1998-01-01

With increase of the number of NPPs and operation history, enhancement of the safety regulation is becoming important for such long-operated NPPs. Centering on the comprehensive preventive maintenance, periodic safety reviews by utilities and its review and evaluation by MITI are in progress. The first reviews have not revealed essential and critical indications to be newly implemented. This means that the most of activities to secure reliability and safety have been done steadily. The present paper addresses the mechanism of on-going preventive maintenance and its essential elements: opportunities to identify issues and problems, and supporting activities to promote decision-makings on feedback, upgrading and modernization of NPPs. (author)

Operations and maintenance - Safety challenges

Energy Technology Data Exchange (ETDEWEB)

Nielsen, Liv [Oljedirektoratet, Stavanger (Norway)

1999-07-01

With the unsteady oil prices and the possible consequences of the deregulation of the European energy markets one may expect further optimization of operating and maintenance costs. One may also expect extended use of various risk-based optimization techniques such as RCM (Reliability Centered Maintenance) and RBI (Risk Based Inspection). This presentation addresses the need for further research and development in this area. Maintenance work is necessary, but it can also create risk. The accident statistics show many examples of this. The Norwegian petroleum industry's ability to learn from previous incidents is questioned. Maintenance staff must be well trained and possess the necessary routines. Technical documentation must be updated. Uncertainties with respect to future oil and gas prices combined with the effect of the deregulation of the European energy markets will lead to even more focus on cost-effective operations and maintenance. The need for long-term research and development is stressed. Risk based techniques such as RCM and RBI are extensively used in the defence industry and the nuclear industry, but applying them to the petroleum industry requires improved risk models. Ageing effects such as corrosion, erosion, fatigue etc. can be expected, but the capability to predict, monitor and control them should be improved. At present, not even the most sophisticated risk analysis can model ageing effects. The importance of efficient use of information technology (IT) is stressed. Improving the product quality and safety often requires new technology and so research and development is important. Close cooperation with the industry is required.

Collaborative learning in condition based maintenance

NARCIS (Netherlands)

Koochaki, J.; Ao, SI; Gelman, L; Hukins, DWL; Hunter, A; Korsunsky, AM

2009-01-01

In recent years, the importance of reliable and consistent production equipments has increased. As a result, companies are shifting their maintenance policy from preventive maintenance towards Condition Based Maintenance (CBM). Despite the growing trend in this area and success stories of CBM

Optimizing preventive maintenance policy: A data-driven application for a light rail braking system.

Science.gov (United States)

Corman, Francesco; Kraijema, Sander; Godjevac, Milinko; Lodewijks, Gabriel

2017-10-01

This article presents a case study determining the optimal preventive maintenance policy for a light rail rolling stock system in terms of reliability, availability, and maintenance costs. The maintenance policy defines one of the three predefined preventive maintenance actions at fixed time-based intervals for each of the subsystems of the braking system. Based on work, maintenance, and failure data, we model the reliability degradation of the system and its subsystems under the current maintenance policy by a Weibull distribution. We then analytically determine the relation between reliability, availability, and maintenance costs. We validate the model against recorded reliability and availability and get further insights by a dedicated sensitivity analysis. The model is then used in a sequential optimization framework determining preventive maintenance intervals to improve on the key performance indicators. We show the potential of data-driven modelling to determine optimal maintenance policy: same system availability and reliability can be achieved with 30% maintenance cost reduction, by prolonging the intervals and re-grouping maintenance actions.

Excellence method in maintenance with application for cryogenic nuclear unit (EMAC)

International Nuclear Information System (INIS)

Anghel, Vasile

2006-01-01

Full text: Cryogenic Nuclear Plant (CNP) has as main objectives the development of a technology for the removal of tritium from heavy water used in nuclear plants of CANDU type and finding of a methodology for complete inspection of the equipment used in the presence of tritium at very low temperatures. These aims imply achieving two main stages. The first stage concerns the maintenance conception on a scientific basis, while the second stage concerns the implementation. The first stage implies the management of maintenance in constraints relating to quality, risk and cost. The second stage regards the aspect of design and technology of CNP maintenance. The solution adequate with this conception will lead to a solution viable for implementation. The operative maintenance will be based on RCM (Reliability Centered Maintenance), using NOLAN and HEAP 1978 methodologies. The integrated maintenance through research and implementation demonstrates the design, realization of equipment, the dynamic and and the static complex uses of EMAC in CNP. It is a method of conception and implementation that integrates maintenance for the life cycle in the considered cryogenics systems. The implementation is achieved by means of the software LabVIEW applied to the specific objectives of the Program for Operative Maintenance in Temporal Dynamic Regime (POMTDR). (author)

Configuration management of on-line maintenance

International Nuclear Information System (INIS)

Grantom, C.R.

1996-01-01

Maintenance activities are performed on station equipment to ensure continued safe and reliable performance. Equipment reliability is thereby improved, resulting in greater confidence that the component will be capable of performing its intended (safety) function. Probabilistic Safety Assessments (PSAs) consider equipment reliability and availability to calculate Core Damage Frequency (CDF) and other risk-related values. Since maintenance activities are included in PSA analyses, the effect of equipment outages on CDF can be analyzed. Results from these types of studies can be scaled to reflect different time periods and show the time-dependent impact of planned equipment outages on CDF. These time-dependent impacts on CDF are graphically presented and referred to as ''risk profiles''. Risk profiles are being successfully used at the South Texas Project (STP) to plan preventive maintenance activities and to assess the impact of unplanned maintenance activities on plant safety. At STP, planned maintenance activities are scheduled to minimize the risk impact of unavailable equipment and to prevent the Occurrence of undesirable plant configurations. The features of the risk profiles used at STP enable the evaluation of both work scope and duration of maintenance activities to be evaluated. This is possible since the risk profile illustrates both instantaneous CDF effects and cumulative impacts to CDF

Economic evaluation of reliability-centred maintenance (RCM): an electricity transmission industry perspective

International Nuclear Information System (INIS)

Bowler, D.J.; Primrose, P.L.; Leonard, R.

1995-01-01

Traditional approaches to appraising the introduction of reliability centred maintenance (RCM) are shown to exhibit severe limitations. In particular, the economic implications surrounding its adoption are repeatedly mis-stated, with the consequence that organisations may be investing in unprofitable RCM ventures. Previously quoted benefits are examined and, contrary to established opinion, it is shown that these 'generalised' statements, once redeemed, are able to be quantified. The paper then proceeds to describe a financial methodology, developed by NGC and UMIST, by which the introduction of RCM can be evaluated. Moreover, it shows that, by regarding RCM as an investment decision, rather than an 'act of faith', the economic viability of a potential application can be determined before vital resources are committed. Finally, it is demonstrated that when the methodology is applied within the context of the electricity transmission industry, the economic case underlying the adoption of RCM can be realistically appraised. (author)

Proceedings of the international workshop on reliability data collection in support of PSA, maintenance and life-assurance programmes

International Nuclear Information System (INIS)

1996-01-01

The utilisation of data to support Probabilistic Safety Assessments, Maintenance Activities and Life-Assurance Programmes is becoming more widely recognized as these areas become more and more developed throughout the nuclear industry. Almost every member country of the OECD Nuclear Energy Agency uses PSA in one way or another in their assessment of nuclear power plant safety. A majority of utilities and licensees have completed or are in the process of planning plant specific PSAs. Operability costs associated with maintenance activities and life assurance programmes are highly dependent upon the data and how it is utilized. Considering these statements and the various suggestions made, the Workshop addressed the following topics concerning reliability data collection: data compilation systems; data bases development and management; data application; parameter estimation; common cause failure and dependent failure data

Proceedings of the international workshop on reliability data collection in support of PSA, maintenance and life-assurance programmes

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-07-01

The utilisation of data to support Probabilistic Safety Assessments, Maintenance Activities and Life-Assurance Programmes is becoming more widely recognized as these areas become more and more developed throughout the nuclear industry. Almost every member country of the OECD Nuclear Energy Agency uses PSA in one way or another in their assessment of nuclear power plant safety. A majority of utilities and licensees have completed or are in the process of planning plant specific PSAs. Operability costs associated with maintenance activities and life assurance programmes are highly dependent upon the data and how it is utilized. Considering these statements and the various suggestions made, the Workshop addressed the following topics concerning reliability data collection: data compilation systems; data bases development and management; data application; parameter estimation; common cause failure and dependent failure data

Optimization of maintenance periodicity of complex of NPP safety systems

International Nuclear Information System (INIS)

Kolykhanov, V.; Skalozubov, V.; Kovrigkin, Y.

2006-01-01

The analysis of the positive and negative aspects connected to maintenance of the safety systems equipment which basically is in a standby state is executed. Tests of systems provide elimination of the latent failures and raise their reliability. Poor quality of carrying out the tests can be a source of the subsequent failures. Therefore excess frequency of tests can result in reducing reliability of safety systems. The method of optimization of maintenance periodicity of the equipment taking into account factors of its reliability and restoration procedures quality is submitted. The unavailability factor is used as a criterion of optimization of maintenance periodicity. It is offered to use parameters of reliability of the equipment and each of safety systems of NPPs received at developing PSA. And it is offered to carry out the concordance of maintenance periodicity of systems within the NPP maintenance program taking into account a significance factor of the system received on the basis of the contribution of system in CDF. Basing on the submitted method the small computer code is developed. This code allows to calculate reliability factors of a separate safety system and to determine optimum maintenance periodicity of its equipment. Optimization of maintenance periodicity of a complex of safety systems is stipulated also. As an example results of optimization of maintenance periodicity at Zaporizhzhya NPP are presented. (author)

A reliability program for emergency diesel generators at nuclear power plants: Maintenance, surveillance, and condition monitoring

International Nuclear Information System (INIS)

Lofgren, E.V.; Henderson, W.; Burghardt, D.; Kripps, L.; Rothleder, B.

1988-12-01

This report is a companion report on NUREG/CR-5078, Volume 1, ''A Reliability Program for Emergency Diesel Generators at Nuclear Power Plants: Program Structure.'' The purpose of this report is to provide technical findings and insights related to: failure evaluation, troubleshooting, maintenance, surveillance, and condition monitoring. Examples and recommendations are provided for each of these areas based on actual emergency diesel generator (EDG) operating experience and the opinions of diesel generator experts. This report expands the more general guidance provided in Volume 1. In addition, a discussion of EDG interactions with other plant systems (e.g., instrument, air, service water, dc power) is provided since experience has shown that these support systems and their operation can adversely affect EDG reliability. Portions of this report have been designed for use by onsite personnel for evaluating operational characteristics of EDGs. 5 refs., 8 figs., 7 tabs

Operational reliability management; Gestao da confiabilidade operacional

Energy Technology Data Exchange (ETDEWEB)

Bressan, Edemir [Refinaria Alberto Pasqualini (REFAP), Canoas, RS (Brazil). Setor de Tecnologia de Equipamentos

2000-07-01

It is described the PETROBRAS Alberto Pasqualini Refinery process plant reliability management, strategies, maintenance organizational structure, management processes, predictive and preventive maintenance, condition monitoring techniques, reliability metrics, pointing out a need for close work relationship between production, maintenance and project engineering functions with highly qualified and committed proper teams, in order to reach one of the highest mechanical availability among Latin America refineries. (author)

City gates maintenance - TBG experience; Experiencia da TBG na manutencao de estacoes de entrega de gas natural

Energy Technology Data Exchange (ETDEWEB)

Rocha, Adir de Brito; Tavares, Cipriano Homem; Pinto, Jose Eduardo Christovao [Transportadora Brasileira Gasoduto Bolivia-Brasil, S.A., Rio de Janeiro, RJ (Brazil)

2005-07-01

Owner and sole operator in Brasilian territory of the Bolivia-Brazil Gas Pipeline (GASBOL), the largest of its kind in South America, TBG started operations on July 1 st, 1999. Since then, it has ensured transportation of Bolivian natural gas into Brazil swiftly and safely. This paper relates the TBG experiences on Natural Gas City Gates maintenance and its components like filtering, heating, pressure reducing redundant valves, turbine meters, flow computers, solar panel power supply, satellite monitoring system, acquired by 6 years of operation of Brazil Bolivia Gas Pipe Line. It describes the definitions of maintenance plans using RCM - Reliability-centered Maintenance concepts and the most important learning experiences. (author)

Maintenance Decision Based on Data Fusion of Aero Engines

Directory of Open Access Journals (Sweden)

Huawei Wang

2013-01-01

Full Text Available Maintenance has gained a great importance as a support function for ensuring aero engine reliability and availability. Cost-effectiveness and risk control are two basic criteria for accurate maintenance. Given that aero engines have much condition monitoring data, this paper presents a new condition-based maintenance decision system that employs data fusion for improving accuracy of reliability evaluation. Bayesian linear model has been applied, so that the performance degradation evaluation of aero engines could be realized. A reliability evaluation model has been presented based on gamma process, which achieves the accurate evaluation by information fusion. In reliability evaluation model, the shape parameter is estimated by the performance degradation evaluation result, and the scale parameter is estimated by failure, inspection, and repair information. What is more, with such reliability evaluation as input variables and by using particle swarm optimization (PSO, a stochastic optimization of maintenance decision for aircraft engines has been presented, in which the effectiveness and the accuracy are demonstrated by a numerical example.

Benchmarking of the maintenance cost in HEPT Centers

CERN Document Server

Béjar-Alonso, Isabel; Rühl, I; CERN. Geneva. ST Division

2002-01-01

This article is the follow up of the paper "Analyse of maintenance cost in ST" presented at the 4th Workshop in Chamonix. Last year the equipment was grouped into families and the ratio of the maintenance cost over the replacement value for each family was calculated. This was done to make an evaluation of the level of maintenance compared with other similar laboratories. This paper shows the result of this comparison. The paper tries to highlight the problem evaluating the level of maintenance and the use of resources. With scarce resources available the division has to make sure that they are allocated and followed up in the best possible and optimal way. "Input" or "quantitative" measurements will therefore have to be combined with performance indicators. This is the only way to measure and evaluate the effect the use of resources has on the output

Transfer of infrared thermography predictive maintenance technologies to Soviet-designed nuclear power plants: experience at Chernobyl

Science.gov (United States)

Pugh, Ray; Huff, Roy

1999-03-01

The importance of infrared (IR) technology and analysis in today's world of predictive maintenance and reliability- centered maintenance cannot be understated. The use of infrared is especially important in facilities that are required to maintain a high degree of equipment reliability because of plant or public safety concerns. As with all maintenance tools, particularly those used in predictive maintenance approaches, training plays a key role in their effectiveness and the benefit gained from their use. This paper details an effort to transfer IR technology to Soviet- designed nuclear power plants in Russia, Ukraine, and Lithuania. Delivery of this technology and post-delivery training activities have been completed recently at the Chornobyl nuclear power plant in Ukraine. Many interesting challenges were encountered during this effort. Hardware procurement and delivery of IR technology to a sensitive country were complicated by United States regulations. Freight and shipping infrastructure and host-country customs policies complicated hardware transport. Training activities were complicated by special hardware, software and training material translation needs, limited communication opportunities, and site logistical concerns. These challenges and others encountered while supplying the Chornobyl plant with state-of-the-art IR technology are described in this paper.

Knowledge engineering thinking of maintenance

International Nuclear Information System (INIS)

2007-01-01

Maintenance optimization problem could not always settled mathematically and was obliged to use quasi-optimum solution with omitting non-formulated limiting condition or neglecting part of optimization object. In such a case knowledge engineering thinking was encouraged. Maintenance of complicated plant and artificial system should be considered from artificial object (equipment/facility hardware and system), technical information and knowledge base, and organizational and human aspect or society and institution. Comprehensive management system in organization and society was necessary not only for assuring integrity of equipment but also for attaining higher performance, reliability and economics of system. For better judgment it was important to share mechanism to make use of more information with organization or whole society. It was required to create database and data mining for knowledge base management system of maintenance. Maintenance was called 'last fortress' to assure quality such as reliability and safety of required function of equipment. Strategic approach to develop maintenance technology under cooperation was considered. Life extension R and D road map was launched in 2005. (T. Tanaka)

Optimum Maintenance Strategies for Highway Bridges

DEFF Research Database (Denmark)

Frangopol, Dan M.; Thoft-Christensen, Palle; Das, Parag C.

As bridges become older and maintenance costs become higher, transportation agencies are facing challenges related to implementation of optimal bridge management programs based on life cycle cost considerations. A reliability-based approach is necessary to find optimal solutions based on minimum...... expected life-cycle costs or maximum life-cycle benefits. This is because many maintenance activities can be associated with significant costs, but their effects on bridge safety can be minor. In this paper, the program of an investigation on optimum maintenance strategies for different bridge types...... is described. The end result of this investigation will be a general reliability-based framework to be used by the UK Highways Agency in order to plan optimal strategies for the maintenance of its bridge network so as to optimize whole-life costs....

Nuclear power plant reliability database management

International Nuclear Information System (INIS)

Meslin, Th.; Aufort, P.

1996-04-01

In the framework of the development of a probabilistic safety project on site (notion of living PSA), Saint Laurent des Eaux NPP implements a specific EDF reliability database. The main goals of this project at Saint Laurent des Eaux are: to expand risk analysis and to constitute an effective local basis of thinking about operating safety by requiring the participation of all departments of a power plant: analysis of all potential operating transients, unavailability consequences... that means to go further than a simple culture of applying operating rules; to involve nuclear power plant operators in experience feedback and its analysis, especially by following up behaviour of components and of safety functions; to allow plant safety managers to outline their decisions facing safety authorities for notwithstanding, preventive maintenance programme, operating incident evaluation. To hit these goals requires feedback data, tools, techniques and development of skills. The first step is to obtain specific reliability data on the site. Raw data come from plant maintenance management system which processes all maintenance activities and keeps in memory all the records of component failures and maintenance activities. Plant specific reliability data are estimated with a Bayesian model which combines these validated raw data with corporate generic data. This approach allow to provide reliability data for main components modelled in PSA, to check the consistency of the maintenance program (RCM), to verify hypothesis made at the design about component reliability. A number of studies, related to components reliability as well as decision making process of specific incident risk evaluation have been carried out. This paper provides also an overview of the process management set up on site from raw database to specific reliability database in compliance with established corporate objectives. (authors). 4 figs

Nuclear power plant reliability database management

Energy Technology Data Exchange (ETDEWEB)

Meslin, Th [Electricite de France (EDF), 41 - Saint-Laurent-des-Eaux (France); Aufort, P

1996-04-01

In the framework of the development of a probabilistic safety project on site (notion of living PSA), Saint Laurent des Eaux NPP implements a specific EDF reliability database. The main goals of this project at Saint Laurent des Eaux are: to expand risk analysis and to constitute an effective local basis of thinking about operating safety by requiring the participation of all departments of a power plant: analysis of all potential operating transients, unavailability consequences... that means to go further than a simple culture of applying operating rules; to involve nuclear power plant operators in experience feedback and its analysis, especially by following up behaviour of components and of safety functions; to allow plant safety managers to outline their decisions facing safety authorities for notwithstanding, preventive maintenance programme, operating incident evaluation. To hit these goals requires feedback data, tools, techniques and development of skills. The first step is to obtain specific reliability data on the site. Raw data come from plant maintenance management system which processes all maintenance activities and keeps in memory all the records of component failures and maintenance activities. Plant specific reliability data are estimated with a Bayesian model which combines these validated raw data with corporate generic data. This approach allow to provide reliability data for main components modelled in PSA, to check the consistency of the maintenance program (RCM), to verify hypothesis made at the design about component reliability. A number of studies, related to components reliability as well as decision making process of specific incident risk evaluation have been carried out. This paper provides also an overview of the process management set up on site from raw database to specific reliability database in compliance with established corporate objectives. (authors). 4 figs.

Status and problem for Nuclear Power Plant Maintenance Training Center

International Nuclear Information System (INIS)

Nanjoh, Takuo

1991-01-01

The Nuclear Power Plant Maintenance Training Center of Kansai Electric Power Co., Inc. was founded in October, 1983, and seven years elapsed since then. The education and training of 37,000 persons were carried out to meet the situation in the plants and to enhance the facilities. Though the main policy of the practical training for preventing the recurrence of troubles does not change, the situation changed from the time of the foundation, and the role has expanded, including PA activities. The see-through plant model installed for technical education in April, 1989 is the about 1/25 scale model of the actual machine with two loops, which actually generates steam and slight electric power, and is useful for promoting the understanding of nuclear power generation theory. It accomplishes the important role that the visitors to the Center (7500 persons in 1989 fiscal year) understand the mechanism of nuclear power generation. In 1990, the education curriculum, the method of education, the time of education and so on are reviewed, aiming at the improvement of education. The execution of education and training, the training of practical techniques, the reflection of the examples of troubles to education, and the expansion of facilities are reported. (K.I.)

Offshore wind turbines reliability, availability and maintenance

CERN Document Server

Tavner, Peter

2012-01-01

The first book to specifically focus on offshore wind turbine technology and which addresses practically wind turbine reliability and availability. The book draws on the author's experience of power generation reliability and availability and the condition monitoring of that plant to describe the problems facing the developers of offshore wind farms and the solutions available to them to raise availability, reduce cost of energy and improve through life cost.

Benefits of a systematic approach to maintenance for safety and safety related systems

International Nuclear Information System (INIS)

Dam, R.F.; Ayazzudin, S.; Nickerson, J.H.

2003-01-01

For safety and safety-related systems, nuclear plants have to balance the requirements of demonstrating the reliability of each system, while maintaining the system and plant availability. With the goal of demonstrating statistical reliability, these systems have extensive testing programs, which often results in system unavailability and this can impact the plant capacity. The inputs to the process are often safety and regulatory related, resulting in programs that provide a high level of scrutiny. In such cases, the value of the application of a Systematic Assessment of Maintenance (SAM) process, such as Reliability Centered Maintenance (RCM), is questioned. The special case of Standby-Safety systems was discussed in a previous paper, where it was demonstrated how SAM techniques provide useful insight into current system performance, the impact of testing on component and system reliability, and how PSA considerations can be integrated into a comprehensive Maintenance, Surveillance, and Inspection (MSI) strategy. Although the system reliability requirements are an important part of the strategy evaluation, SAM techniques provide a systematic assessment within a broader context. Testing is only one part of an overall strategy focused on ensuring that component function is maintained through a combination of monitoring technologies (including testing), predictive techniques, and intrusive maintenance strategies. Each strategy is targeted to known component degradation mechanisms. This thinking can be extended to safety and safety related systems in general. Over the past 6 years, AECL has been working with CANDU utilities in the development and implementation of a comprehensive and integrated Plant Life Management (PLiM) program. As part of developing a comprehensive plant asset management approach, SAM techniques are used to develop a technical basis that not only works towards ensuring reliable operation of plant systems, but also facilitates the optimization and

Multiple Shh signaling centers participate in fungiform papilla and taste bud formation and maintenance.

Science.gov (United States)

Liu, Hong Xiang; Ermilov, Alexandre; Grachtchouk, Marina; Li, Libo; Gumucio, Deborah L; Dlugosz, Andrzej A; Mistretta, Charalotte M

2013-10-01

The adult fungiform taste papilla is a complex of specialized cell types residing in the stratified squamous tongue epithelium. This unique sensory organ includes taste buds, papilla epithelium and lateral walls that extend into underlying connective tissue to surround a core of lamina propria cells. Fungiform papillae must contain long-lived, sustaining or stem cells and short-lived, maintaining or transit amplifying cells that support the papilla and specialized taste buds. Shh signaling has established roles in supporting fungiform induction, development and patterning. However, for a full understanding of how Shh transduced signals act in tongue, papilla and taste bud formation and maintenance, it is necessary to know where and when the Shh ligand and pathway components are positioned. We used immunostaining, in situ hybridization and mouse reporter strains for Shh, Ptch1, Gli1 and Gli2-expression and proliferation markers to identify cells that participate in hedgehog signaling. Whereas there is a progressive restriction in location of Shh ligand-expressing cells, from placode and apical papilla cells to taste bud cells only, a surrounding population of Ptch1 and Gli1 responding cells is maintained in signaling centers throughout papilla and taste bud development and differentiation. The Shh signaling targets are in regions of active cell proliferation. Using genetic-inducible lineage tracing for Gli1-expression, we found that Shh-responding cells contribute not only to maintenance of filiform and fungiform papillae, but also to taste buds. A requirement for normal Shh signaling in fungiform papilla, taste bud and filiform papilla maintenance was shown by Gli2 constitutive activation. We identified proliferation niches where Shh signaling is active and suggest that epithelial and mesenchymal compartments harbor potential stem and/or progenitor cell zones. In all, we report a set of hedgehog signaling centers that regulate development and maintenance of taste

Some areas of reliability technique which have been neglected to some extent - maintainability - human reliability - mechanical reliability - repairable systems

International Nuclear Information System (INIS)

Akersten, P.A.

1985-01-01

The present thesis consists of four papers, three of which are of a expositary nature and one more theoretical. The first two papers have a natural coupling to the man-machine interface. The first paper is devoted to the concept of maintainability and the role of man as maintenance technician. The second paper discusses aspects of human reliability, mainly studying man as operator. However, maintenance tasks can be studied in the same manner. The third paper concerns reliability prediction for mechanical components. This is an area of vital importance for the reliability practitioner, who needs realistic and easy-to-use mathematical models for different failure modes. The fourth paper discusses mathematical models for repairable systems, especially the problem of testing whether a constant event intensity model is adequate or not. (author)

Hardware and software maintenance strategies for upgrading vintage computers

International Nuclear Information System (INIS)

Wang, B.C.; Buijs, W.J.; Banting, R.D.

1992-01-01

The paper focuses on the maintenance of the computer hardware and software for digital control computers (DCC). Specific design and problems related to various maintenance strategies are reviewed. A foundation was required for a reliable computer maintenance and upgrading program to provide operation of the DCC with high availability and reliability for 40 years. This involved a carefully planned and executed maintenance and upgrading program, involving complementary hardware and software strategies. The computer system was designed on a modular basis, with large sections easily replaceable, to facilitate maintenance and improve availability of the system. Advances in computer hardware have made it possible to replace DCC peripheral devices with reliable, inexpensive, and widely available components from PC-based systems (PC = personal computer). By providing a high speed link from the DCC to a PC, it is now possible to use many commercial software packages to process data from the plant. 1 fig

Improving machinery reliability

CERN Document Server

Bloch, Heinz P

1998-01-01

This totally revised, updated and expanded edition provides proven techniques and procedures that extend machinery life, reduce maintenance costs, and achieve optimum machinery reliability. This essential text clearly describes the reliability improvement and failure avoidance steps practiced by best-of-class process plants in the U.S. and Europe.

On the optimal scheduling of periodic tests and maintenance for reliable redundant components

International Nuclear Information System (INIS)

Courtois, Pierre-Jacques; Delsarte, Philippe

2006-01-01

Periodically, some m of the n redundant components of a dependable system may have to be taken out of service for inspection, testing or preventive maintenance. The system is then constrained to operate with lower (n-m) redundancy and thus with less reliability during these periods. However, more frequent periodic inspections decrease the probability that a component fail undetected in the time interval between successive inspections. An optimal time schedule of periodic preventive operations arises from these two conflicting factors, balancing the loss of redundancy during inspections against the reliability benefits of more frequent inspections. Considering no other factor than this decreased redundancy at inspection time, this paper demonstrates the existence of an optimal interval between inspections, which maximizes the mean time between system failures. By suitable transformations and variable identifications, an analytic closed form expression of the optimum is obtained for the general (m, n) case. The optimum is shown to be unique within the ranges of parameter values valid in practice; its expression is easy to evaluate and shown to be useful to analyze and understand the influence of these parameters. Inspections are assumed to be perfect, i.e. they cause no component failure by themselves and leave no failure undetected. In this sense, the optimum determines a lowest bound for the system failure rate that can be achieved by a system of n-redundant components, m of which require for inspection or maintenance recurrent periods of unavailability of length t. The model and its general closed form solution are believed to be new . Previous work had computed optimal values for an estimation of a time average of system unavailability, but by numerical procedures only and with different numerical approximations, other objectives and model assumptions (one component only inspected at a time), and taking into account failures caused by testing itself, repair and

University of Tennessee - Industry collaborative research and development in preventive maintenance technology

International Nuclear Information System (INIS)

Upadhyaya, B.R.

1992-01-01

The Preventive Maintenance Engineering Laboratory (PMEL) was inaugurated at the University of Tennessee Nuclear Engineering Department in September 1989. The startup funding was provided by Gilbert/Commonwealth, Inc. The purpose of PMEL is to identify maintenance-related problems in the power and process industries and to find their solutions through the development and application of emerging technologies. These include advanced digital signal processing, applied artificial intelligence (AI), artificial neural networks, and reliability based methods. The Laboratory activities are being expanded by the formation of an industrial consortium within the Measurement and Control Engineering Center at the University of Tennessee. Several research and development projects in preventive maintenance are being carried out. These include condition monitoring of air operated valves, automated diagnostics of motor operated valves, instrument calibration, verification, and estimation of expected residual life of electric motors using applied AI technology and reliability-based methods. The new methodology will be applied to other industrial subsystems. A long-term research and development project is being sponsored by the T.V.A. Nuclear Maintenance Department. The overall objective of the research program is to develop and apply advanced artificial intelligence and information processing methods to the problems of plant performance monitoring and preventive maintenance. The program includes the development of a workstation/PC-based, networking of plant information for easy access to operational and management personnel, implementation of a sensor verification system, monitoring of feedwater flow venturi fouling and heat rate balance, and integration of signal validation, command validation, and fault-tolerant control strategies

Maintenance optimization for subsea oil pipelines

International Nuclear Information System (INIS)

Castanier, Bruno; Rausand, Marvin

2006-01-01

In this paper, the classical PF interval model, proposed for reliability centered maintenance, is used to optimize the preventive replacement policy of a subsea oil pipeline. The pipeline is subject to failure modes that may lead to oil release and pollution of the sea. The proposed replacement policy is based on regular condition measurements of the quality of an internal pipeline coating (lining). Holes in the coating will expose the pipe material (steel) to a corrosive environment. It is, therefore, important to identify holes in the coating and take action before the corrosion penetrates the pipe wall. The model proposed in the paper can be used to determine the inspection interval that minimizes the average maintenance cost per time unit. The model formulation is outlined and illustrative examples are solved. The mathematical evaluation of the replacement policy requires numerous assumptions. These assumptions have to be tailored to the specific application. The assumptions and the data provided are included for illustrative purposes to exemplify potential results that may be obtained by using the replacement policy

Framework for Maintenance Planning

DEFF Research Database (Denmark)

Soares, C. Guedes; Duarte, J. Caldeira; Garbatov, Y.

2010-01-01

the design and during the whole life span of operational use, within an integrated framework founded on risk and reliability based techniques. The document addresses designers, decision makers and professionals responsible for or involved in establishing maintenance plans. The purpose of this document......The present document presents a framework for maintenance planning. Maintenance plays a fundamental role in counteracting degradation effects, which are present in all infrastructure and industrial products. Therefore, maintenance planning is a very critical aspect to consider both during...... is to present maintenance as an integrated approach that needs to be planned, designed, engineered, and controlled by proper qualitative and quantitative techniques. This document outlines the basic premises for maintenance planning and provides the general philosophies that can be followed and points to a best...

Condition based maintenance pilot projects at Pickering ND

International Nuclear Information System (INIS)

Zemdegs, R.T.

1995-01-01

Ontario Hydro has recognized that the approaches to maintenance have undergone significant changes to the past decades. The traditional break down maintenance approach has been replaced by preventative maintenance and more recently, by condition based maintenance. The nuclear plants of Ontario Hydro have evaluated on a number of alternative programs to improve their maintenance effectiveness and to reduce costs, including Reliability Centred Maintenance (RCM), call-up review, component-based PM programs, analysis of failure history and so on. Pickering ND (nuclear division) and Ontario Hydro's Nuclear Technologies Services Division, have embarked on a Condition Based Maintenance pilot project to address the above issues as a breakthrough solution for smarter maintenance. The Condition Based Maintenance pilot project will demonstrate an end-to-end process utilizing a Reliability Centred Maintenance structured approach to re-engineer and redefine the existing maintenance programs. The project emphasizes on-condition maintenance where justified, and utilizes an information management tool to provide the required records keeping and analysis infrastructure. This paper briefly describes the planned maintenance model at Pickering ND used to guide the CBM pilot, and an overview of the methodology used to develop on-condition equipment indicators as part of a re-engineered maintenance plan

Two Different Maintenance Strategies in the Hospital Environment: Preventive Maintenance for Older Technology Devices and Predictive Maintenance for Newer High-Tech Devices.

Science.gov (United States)

Sezdi, Mana

2016-01-01

A maintenance program generated through the consideration of characteristics and failures of medical equipment is an important component of technology management. However, older technology devices and newer high-tech devices cannot be efficiently managed using the same strategies because of their different characteristics. This study aimed to generate a maintenance program comprising two different strategies to increase the efficiency of device management: preventive maintenance for older technology devices and predictive maintenance for newer high-tech devices. For preventive maintenance development, 589 older technology devices were subjected to performance verification and safety testing (PVST). For predictive maintenance development, the manufacturers' recommendations were used for 134 high-tech devices. These strategies were evaluated in terms of device reliability. This study recommends the use of two different maintenance strategies for old and new devices at hospitals in developing countries. Thus, older technology devices that applied only corrective maintenance will be included in maintenance like high-tech devices.

History of Reliability and Quality Assurance at Kennedy Space Center

Science.gov (United States)

Childers, Frank M.

2004-01-01

This Kennedy Historical Document (KHD) provides a unique historical perspective of the organizational and functional responsibilities for the manned and un-manned programs at Kennedy Space Center, Florida. As systems become more complex and hazardous, the attention to detailed planning and execution continues to be a challenge. The need for a robust reliability and quality assurance program will always be a necessity to ensure mission success. As new space missions are defined and technology allows for continued access to space, these programs cannot be compromised. The organizational structure that has provided the reliability and quality assurance functions for both the manned and unmanned programs has seen many changes since the first group came to Florida in the 1950's. The roles of government and contractor personnel have changed with each program and organizational alignment has changed based on that responsibility. The organizational alignment of the personnel performing these functions must ensure independent assessment of the processes.

Proficiency evaluation of maintenance personnel: Training equivalency determination

International Nuclear Information System (INIS)

Price, W.J.

1991-01-01

The nuclear industry has recognized the importance of safe, quality, productive maintenance practices and has taken a number of initiatives that have generally improved maintenance programs. Because proficient maintenance practices are critical to plant safety and reliability, most plants have also recognized the need for reliable, valid testing techniques that demonstrate and assure the competence of their maintenance personnel. Until now, resource demands were too great to develop in-plant testing programs. In the past, maintenance supervisors have exempted personnel from training, using informal judgment of the employees' previous training and experience and informal observation of the employee on the job. While this procedure may have some degree of validity, it fails to provide the documentation for training equivalency that is required to satisfy the US Nuclear Regulatory Commission (NRC) regulations and Institute of Nuclear Power Operations (INPO) guidelines. To assess and demonstrate the proficiency levels of personnel, Calvert Cliffs needed to establish an objective, reliable, time-saving, and valid system to evaluate the competency levels of personnel. This was done in a joint effort with the Electric Power Research Institute

Reliability Analysis and Optimal Release Problem Considering Maintenance Time of Software Components for an Embedded OSS Porting Phase

Science.gov (United States)

Tamura, Yoshinobu; Yamada, Shigeru

OSS (open source software) systems which serve as key components of critical infrastructures in our social life are still ever-expanding now. Especially, embedded OSS systems have been gaining a lot of attention in the embedded system area, i.e., Android, BusyBox, TRON, etc. However, the poor handling of quality problem and customer support prohibit the progress of embedded OSS. Also, it is difficult for developers to assess the reliability and portability of embedded OSS on a single-board computer. In this paper, we propose a method of software reliability assessment based on flexible hazard rates for the embedded OSS. Also, we analyze actual data of software failure-occurrence time-intervals to show numerical examples of software reliability assessment for the embedded OSS. Moreover, we compare the proposed hazard rate model for the embedded OSS with the typical conventional hazard rate models by using the comparison criteria of goodness-of-fit. Furthermore, we discuss the optimal software release problem for the porting-phase based on the total expected software maintenance cost.

Methodology for maintenance analysis based on hydroelectric power stations reliability; Metodologia para realizar analisis de mantenimiento basado en confiabilidad en centrales hidroelectricas

Energy Technology Data Exchange (ETDEWEB)

Rea Soto, Rogelio; Calixto Rodriguez, Roberto; Sandoval Valenzuela, Salvador; Velasco Flores, Rocio; Garcia Lizarraga, Maria del Carmen [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

2012-07-01

A methodology to carry out Reliability Centered Maintenance (RCM) studies for hydroelectric power plants is presented. The methodology is an implantation/extension of the guidelines proposed by the Engineering Society for Advanced Mobility Land, Sea and Space in the SAE-JA1012 standard. With the purpose of answering the first five questions, that are set out in that standard, the use of standard ISO14224 is strongly recommended. This approach standardizes failure mechanisms and homogenizes RCM studies with the process of collecting failure and maintenance data. The use of risk matrixes to rank the importance of each failure based on a risk criteria is also proposed. [Spanish] Se presenta una metodologia para realizar estudios de mantenimiento Basado en Confiabilidad (RCM) aplicados a la industria hidroelectrica. La metodologia es una implantacion/ extension realizada por los autores de este trabajo, de los lineamientos propuestos por la Engineering Society for Advanced Mobility Land, Sea and Space en el estandar SAE-JA1012. Para contestar las primeras cinco preguntas del estandar se propone tomar como base los modos y mecanismos de fallas de componentes documentados en la guia para recopilar datos de falla en el estandar ISO-14224. Este enfoque permite estandarizar la descripcion de mecanismos de fallas de los equipos, tanto en el estudio RCM como en el proceso de recopilacion de datos de falla y de mantenimiento, lo que permite retroalimentar el ciclo de mejora continua de los procesos RCM. Tambien se propone el uso de matrices de riesgo para jerarquizar la importancia de los mecanismos de falla con base en el nivel de riesgo.

Lean Maintenance Applied to Improve Maintenance Efficiency in Thermoelectric Power Plants

Directory of Open Access Journals (Sweden)

Orlando Duran

2017-10-01

Full Text Available Thermoelectric power plants consist of a set of critical equipment that require high levels of availability and reliability. Due to this, maintenance of these physical assets is gaining momentum in industry. Maintenance is considered as an activity that contributes to improving the availability, efficiency and productivity of each piece of equipment. Several techniques have been used to achieve greater efficiencies in maintenance, among which we can find the lean maintenance philosophy. Despite the wide diffusion of lean maintenance, there is no structured method that supports the prescription of lean tools applied to the maintenance function. This paper presents the experience gathered in two lean maintenance projects in thermoelectric power plants. The application of lean techniques was based on using a previously developed multicriterial decision making process that uses the Fuzzy Analytic Hierarchy Process (AHP methodology to carry out a diagnosis and prescription tasks. That methodology allowed the prescription of the appropriated lean techniques to resolve the main deficiencies in maintenance function. The results of applying such lean tools show that important results can be obtained, making the maintenance function in thermoelectric power plants more efficient and lean.

Space Flight Operations Center local area network

Science.gov (United States)

Goodman, Ross V.

1988-01-01

The existing Mission Control and Computer Center at JPL will be replaced by the Space Flight Operations Center (SFOC). One part of the SFOC is the LAN-based distribution system. The purpose of the LAN is to distribute the processed data among the various elements of the SFOC. The SFOC LAN will provide a robust subsystem that will support the Magellan launch configuration and future project adaptation. Its capabilities include (1) a proven cable medium as the backbone for the entire network; (2) hardware components that are reliable, varied, and follow OSI standards; (3) accurate and detailed documentation for fault isolation and future expansion; and (4) proven monitoring and maintenance tools.

Maintenance work management system

International Nuclear Information System (INIS)

Kanai, T.; Takahashi, Y.; Takahashi, K.; Nishino, M.; Takeshige, R.

2000-01-01

The maintenance work management system supports the efficient drawing up of various documents for the maintenance work at nuclear power stations and the speeding up of the permission procedure. In addition, it improves the quality assurance of the safety and reliability of the maintenance work. Key merits of the system are: 1. Efficiently drawing up various documents for the maintenance work by using the stored data for the previous maintenance work and the pipe and instrument diagram (P and ID) data. 2. Supporting the management work for the completion of maintenance work safety by using the isolation information stored on the computer system. 3. Speeding up the permission procedure by electronic mail and electronic permission. 4. Displaying additional information such as the specifications of equipment, maintenance result, and maintenance plan by linking up with the database of another system. 5. Reducing the cost of hardware devices by using client/server network configurations of personal computers and a personal computer server. (author)

Value maximizing maintenance policies under general repair

International Nuclear Information System (INIS)

Marais, Karen B.

2013-01-01

One class of maintenance optimization problems considers the notion of general repair maintenance policies where systems are repaired or replaced on failure. In each case the optimality is based on minimizing the total maintenance cost of the system. These cost-centric optimizations ignore the value dimension of maintenance and can lead to maintenance strategies that do not maximize system value. This paper applies these ideas to the general repair optimization problem using a semi-Markov decision process, discounted cash flow techniques, and dynamic programming to identify the value-optimal actions for any given time and system condition. The impact of several parameters on maintenance strategy, such as operating cost and revenue, system failure characteristics, repair and replacement costs, and the planning time horizon, is explored. This approach provides a quantitative basis on which to base maintenance strategy decisions that contribute to system value. These decisions are different from those suggested by traditional cost-based approaches. The results show (1) how the optimal action for a given time and condition changes as replacement and repair costs change, and identifies the point at which these costs become too high for profitable system operation; (2) that for shorter planning horizons it is better to repair, since there is no time to reap the benefits of increased operating profit and reliability; (3) how the value-optimal maintenance policy is affected by the system's failure characteristics, and hence whether it is worthwhile to invest in higher reliability; and (4) the impact of the repair level on the optimal maintenance policy. -- Highlights: •Provides a quantitative basis for maintenance strategy decisions that contribute to system value. •Shows how the optimal action for a given condition changes as replacement and repair costs change. •Shows how the optimal policy is affected by the system's failure characteristics. •Shows when it is

A comparative study on the reliability criteria determination

International Nuclear Information System (INIS)

Jerng, Dong Wook; Ju, Tae Young

2009-01-01

There are two methods to determine the reliability criteria for maintenance effectiveness monitoring; using the failure probability, and the importance from PRA. Comparisons of the results from these two methods provides an insight on the relevancy of setting the reliability criteria to improve the maintenance effectiveness. (author)

Multinomial-exponential reliability function: a software reliability model

International Nuclear Information System (INIS)

Saiz de Bustamante, Amalio; Saiz de Bustamante, Barbara

2003-01-01

The multinomial-exponential reliability function (MERF) was developed during a detailed study of the software failure/correction processes. Later on MERF was approximated by a much simpler exponential reliability function (EARF), which keeps most of MERF mathematical properties, so the two functions together makes up a single reliability model. The reliability model MERF/EARF considers the software failure process as a non-homogeneous Poisson process (NHPP), and the repair (correction) process, a multinomial distribution. The model supposes that both processes are statistically independent. The paper discusses the model's theoretical basis, its mathematical properties and its application to software reliability. Nevertheless it is foreseen model applications to inspection and maintenance of physical systems. The paper includes a complete numerical example of the model application to a software reliability analysis

Performance-based maintenance of gas turbines for reliable control of degraded power systems

Science.gov (United States)

Mo, Huadong; Sansavini, Giovanni; Xie, Min

2018-03-01

Maintenance actions are necessary for ensuring proper operations of control systems under component degradation. However, current condition-based maintenance (CBM) models based on component health indices are not suitable for degraded control systems. Indeed, failures of control systems are only determined by the controller outputs, and the feedback mechanism compensates the control performance loss caused by the component deterioration. Thus, control systems may still operate normally even if the component health indices exceed failure thresholds. This work investigates the CBM model of control systems and employs the reduced control performance as a direct degradation measure for deciding maintenance activities. The reduced control performance depends on the underlying component degradation modelled as a Wiener process and the feedback mechanism. To this aim, the controller features are quantified by developing a dynamic and stochastic control block diagram-based simulation model, consisting of the degraded components and the control mechanism. At each inspection, the system receives a maintenance action if the control performance deterioration exceeds its preventive-maintenance or failure thresholds. Inspired by realistic cases, the component degradation model considers random start time and unit-to-unit variability. The cost analysis of maintenance model is conducted via Monte Carlo simulation. Optimal maintenance strategies are investigated to minimize the expected maintenance costs, which is a direct consequence of the control performance. The proposed framework is able to design preventive maintenance actions on a gas power plant, to ensuring required load frequency control performance against a sudden load increase. The optimization results identify the trade-off between system downtime and maintenance costs as a function of preventive maintenance thresholds and inspection frequency. Finally, the control performance-based maintenance model can reduce

Comparative evaluation of remote maintenance schemes for fusion DEMO reactor

Energy Technology Data Exchange (ETDEWEB)

Utoh, Hiroyasu, E-mail: uto.hiroyasu@jaea.go.jp; Tobita, Kenji; Someya, Youji; Asakura, Nobuyuki; Sakamoto, Yoshiteru; Hoshino, Kazuo; Nakamura, Makoto

2015-10-15

Highlights: • Various remote maintenance schemes for DEMO were comparatively assessed based on requirements for DEMO remote maintenance. • The banana shape segment transport using all vertical maintenance ports would be more probable DEMO reactor maintenance scheme. • The key engineering issues are in-vessel transferring mechanism of segment, pipe connection and conducting shell design for plasma vertical stability. - Abstract: Maintenance schemes are one of the critical issues in DEMO design, significantly affecting the configuration of in-vessel components, the size of toroidal field (TF) coil, the arrangement of poloidal field (PF) coils, reactor building, hot cell and so forth. Therefore, the maintenance schemes should satisfy many design requirements and criteria to assure reliable and safe plant operation and to attain reasonable plant availability. The plant availability depends on reliability of remote maintenance scheme, inspection of pipe connection and plasma operation. In this paper, various remote maintenance schemes for DEMO were comparatively assessed based on requirements for DEMO remote maintenance. From the view points of the reliability of inspection on hot cell, TF coil size, stored energy of PF coil and portability of segment, the banana shape segment transport using all vertical maintenance ports would be more probable DEMO reactor maintenance scheme, and it has key engineering issues such as in-vessel transferring mechanism of segment, pipe connection and conducting shell design for plasma vertical stability.

Comparative evaluation of remote maintenance schemes for fusion DEMO reactor

International Nuclear Information System (INIS)

Utoh, Hiroyasu; Tobita, Kenji; Someya, Youji; Asakura, Nobuyuki; Sakamoto, Yoshiteru; Hoshino, Kazuo; Nakamura, Makoto

2015-01-01

Highlights: • Various remote maintenance schemes for DEMO were comparatively assessed based on requirements for DEMO remote maintenance. • The banana shape segment transport using all vertical maintenance ports would be more probable DEMO reactor maintenance scheme. • The key engineering issues are in-vessel transferring mechanism of segment, pipe connection and conducting shell design for plasma vertical stability. - Abstract: Maintenance schemes are one of the critical issues in DEMO design, significantly affecting the configuration of in-vessel components, the size of toroidal field (TF) coil, the arrangement of poloidal field (PF) coils, reactor building, hot cell and so forth. Therefore, the maintenance schemes should satisfy many design requirements and criteria to assure reliable and safe plant operation and to attain reasonable plant availability. The plant availability depends on reliability of remote maintenance scheme, inspection of pipe connection and plasma operation. In this paper, various remote maintenance schemes for DEMO were comparatively assessed based on requirements for DEMO remote maintenance. From the view points of the reliability of inspection on hot cell, TF coil size, stored energy of PF coil and portability of segment, the banana shape segment transport using all vertical maintenance ports would be more probable DEMO reactor maintenance scheme, and it has key engineering issues such as in-vessel transferring mechanism of segment, pipe connection and conducting shell design for plasma vertical stability.

Job analysis of the electrician position for the nuclear power plant maintenance personnel reliability model

International Nuclear Information System (INIS)

Federman, P.J.; Bartter, W.D.; Siegel, A.I.

1984-02-01

This report presents the methods, procedures, and results of the fourth and final of a series of job analytic studies which characterize maintenance positions in nuclear power plants. The electrician position is the subject of the present report. The characterization of the electrician position takes the form of detailed information about: (1) the frequency of performing various tasks, (2) the time required for performing each task, (3) the training required for adequate performance of each task, and (4) the perceived consequences resulting from inadequate task performance. Additionally, information is presented about the intellective and the perceptual-motor loading imposed by each task. This information contributes to job design and training requirements derivation as well as to the assessment of human performance reliability in nuclear power plants

Job analysis of maintenance-mechanic position for the nuclear power plant maintenance personnel reliability model

International Nuclear Information System (INIS)

Siegel, A.I.; Bartter, W.D.; Kopstein, F.F.

1982-06-01

The task list method of job survey was used. In collaboration with BWR and PWR personnel, a list of 107 tasks performed by maintenance mechanics was developed, grouped into: remove and install, test and repair, inspect and perform preventive maintenance, miscellaneous, communication, and report preparation. For each listed task, the questionnaire form inquired into: frequency of performance, task completion time, safety consequences of improper performance, and the amount of training required to perform the task proficiently. Scaled information was requested about seven abilities: (1) visual speed, accuracy, and recognition; (2) gross motor coordination; (3) fine manual dexterity; (4) strength and stamina; (5) cognition; (6) memory; and (7) problem solving required for function completion. Survey forms were distributed to 27 nuclear power plants. Thirty-one maintenance mechanics representing 17 plants returned the completed forms. Frequency of performing tasks was bimodally distributed: (1) between once a year and once every six months, and (2) about once a week. More than half of the tasks have potential risk consequences if improperly performed. The five tasks with the greatest risk implications in the case of inadequate performance were: (1) remove and install reactor and dry-well heads, (2) test and repair reactor system components, (3) remove and install pressurizer mechanical relief valves, (4) test and repair pressurizer relief valves, (5) remove and install core spray pumps, seals, and valves. Hierarchically, the public risk associated with the various functions was: (1) remove and install, (2) test and repair, (3) preventive maintenance, (4) miscellaneous tasks, (5) communication, and (6) report preparation

Analysis and Application of Reliability

International Nuclear Information System (INIS)

Jeong, Hae Seong; Park, Dong Ho; Kim, Jae Ju

1999-05-01

This book tells of analysis and application of reliability, which includes definition, importance and historical background of reliability, function of reliability and failure rate, life distribution and assumption of reliability, reliability of unrepaired system, reliability of repairable system, sampling test of reliability, failure analysis like failure analysis by FEMA and FTA, and cases, accelerated life testing such as basic conception, acceleration and acceleration factor, and analysis of accelerated life testing data, maintenance policy about alternation and inspection.

Job analysis of the instrument and control technician position for the nuclear power plant maintenance personnel reliability model

International Nuclear Information System (INIS)

Siegel, A.I.; Bartter, W.D.; Federman, P.J.

1983-08-01

This report is one of a series that is planned to describe the results of a program undertaken by the Oak Ridge National Laboratory (ORNL) for the US Nuclear Regulatory Commission, Office of Nuclear Regulatory Research, to define, develop, validate, and disseminate a methodology for the quantitative prediction of human reliability in the conduct of maintenance tasks in nuclear power plants (NPPs). ORNL has subcontracted portions of this effort to Applied Psychological Services, Inc. This report on the job analysis of the Instrument and Control technician (NUREG/CR-3274) and a report on the job analysis of the electrician position (NUREG/CR-3275) comprise a part of the initial efforts of the development phase of this program. With the publication of the job analysis of the electrician position, the series of job analyses reports addressing nuclear power plant maintenance personnel will be complete. Subsequent reports addressing model development and validation are planned

Selective maintenance of multi-state systems with structural dependence

International Nuclear Information System (INIS)

Dao, Cuong D.; Zuo, Ming J.

2017-01-01

This paper studies the selective maintenance problem for multi-state systems with structural dependence. Each component can be in one of multiple working levels and several maintenance actions are possible to a component in a maintenance break. The components structurally form multiple hierarchical levels and dependence groups. A directed graph is used to represent the precedence relations of components in the system. A selective maintenance optimization model is developed to maximize the system reliability in the next mission under time and cost constraints. A backward search algorithm is used to determine the assembly sequence for a selective maintenance scenario. The maintenance model helps maintenance managers in determining the best combination of maintenance activities to maximize the probability of successfully completing the next mission. Examples showing the use of the proposed method are presented. - Highlights: • A selective maintenance model for multi-state systems is proposed considering both economic and structural dependence. • Structural dependence is modeled as precedence relationship when disassembling components for maintenance. • Resources for disassembly and maintenance are evaluated using a backward search algorithm. • Maintenance strategies with and without structural dependence are analyzed. • Ignoring structural dependence may lead to over-estimation of system reliability.

CANDU plant maintenance: Recent developments

International Nuclear Information System (INIS)

Charlebois, P.

2000-01-01

CANDU units have long been recognized for their exceptional safety and reliability. Continuing development in the maintenance area has played a key role in achieving this performance level. For over two decades, safety system availability has been monitored closely and system maintenance programs adjusted accordingly to maintain high levels of performance. But as the plants approach mid life in a more competitive environment and component aging becomes a concern, new methods and techniques are necessary. As a result, recent developments are moving the maintenance program largely from a corrective and preventive approach to predictive and condition based maintenance. The application of these techniques is also being extended to safety related systems. These recent developments include use of reliability centred methods to define system maintenance requirements and strategies. This approach has been implemented on a number of systems at Canadian CANDU plants with positive results. The pilot projects demonstrated that the overall maintenance effort remained relatively constant while the system performance improved. It was also possible to schedule some of the redundant component maintenance during plant operation without adverse impact on system availability. The probabilistic safety assessment was found to be useful in determining the safety implications of component outages. These new maintenance strategies are now making use of predictive and condition based maintenance techniques to anticipate equipment breakdown and schedule preventive maintenance as the need arises rather than time based. Some of these techniques include valve diagnostics, vibration monitoring, oil analysis, thermography. Of course, these tools and techniques must form part of an overall maintenance management system to ensure that maintenance becomes a living program. To facilitate this process and contain costs, new information technology tools are being introduced to provide system engineers

A probabilistic maintenance model for diesel engines

Science.gov (United States)

Pathirana, Shan; Abeygunawardane, Saranga Kumudu

2018-02-01

In this paper, a probabilistic maintenance model is developed for inspection based preventive maintenance of diesel engines based on the practical model concepts discussed in the literature. Developed model is solved using real data obtained from inspection and maintenance histories of diesel engines and experts' views. Reliability indices and costs were calculated for the present maintenance policy of diesel engines. A sensitivity analysis is conducted to observe the effect of inspection based preventive maintenance on the life cycle cost of diesel engines.

Maintenance Management Support Systems for component aging estimation at nuclear power plants

International Nuclear Information System (INIS)

Shimizu, Shunichi; Ando, Yasumasa; Morioka, Toshihiko; Okuzumi, Naoaki

1991-01-01

Maintenance Management Support Systems (MMSSs) for nuclear power plants have been developed using component aging estimation methods and decision tree analysis for maintenance planning. The former evaluates actual component reliability through statistical analysis on field maintenance data. The latter provides preventive maintenance (PM) planning guidance using heuristic expert knowledge and estimated reliability parameters. The following aspects have been investigated: (1) A systematic and effective method of managing components/parts design information and field maintenance data (2) A method for estimating component aging based on a statistical analysis of field maintenance data (3) A method for providing PM planning guidance using estimated component reliability/performance parameters and decision tree analysis. Based on these investigations, two MMSSs were developed. One deals with 'general maintenance data', which are common to all component types and are amenable to common data handling. The other system deals with 'specific maintenance data', which are specific to an individual component type. Both systems provide PM planning guidance for PM cycles propriety and the PM work priority. The function of these systems were verified using simulated maintenance data. (author)

Prediction of attendance at fitness center: a comparison between the theory of planned behavior, the social cognitive theory, and the physical activity maintenance theory

OpenAIRE

Jekauc, Darko; Völkle, Manuel; Wagner, Matthias O.; Mess, Filip; Reiner, Miriam; Renner, Britta

2015-01-01

In the processes of physical activity (PA) maintenance specific predictors are effective, which differ from other stages of PA development. Recently, Physical Activity Maintenance Theory (PAMT) was specifically developed for prediction of PA maintenance. The aim of the present study was to evaluate the predictability of the future behavior by the PAMT and compare it with the Theory of Planned Behavior (TPB) and Social Cognitive Theory (SCT). Participation rate in a fitness center was observed...

Tandem mirror next step: remote maintenance

International Nuclear Information System (INIS)

Doggett, J.N.; Damm, C.C.; Hanson, C.L.

1980-01-01

This study of the next proposed experiment in the Mirror Fusion Program, the Tandem Mirror Next Step (TMNS), has included serious consideration of the maintenance requirements of such a large source of high energy neutrons with its attendant throughput of tritium. Although maintenance will be costly in time and money, our conclusion is that with careful attention to a design for maintenance plan such a device can be reliably operated

Proceedings of the third international conference on CANDU maintenance

International Nuclear Information System (INIS)

1995-01-01

The third international conference on Candu maintenance included sessions on the following topics: predictive maintenance, reliability improvements, steam generator monitoring, tools and instrumentation, valve performance, fuel channel inspection and maintenance, steam generator maintenance, environmental qualification, predictive maintenance, instrumentation and control, steam generator cleaning, decontamination and radiation protection, inspection techniques, maintenance program strategies and valve packing experience, remote tooling/ robotics and fuel handling. The individual papers have been abstracted separately

Proceedings of the third international conference on CANDU maintenance

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-12-31

The third international conference on Candu maintenance included sessions on the following topics: predictive maintenance, reliability improvements, steam generator monitoring, tools and instrumentation, valve performance, fuel channel inspection and maintenance, steam generator maintenance, environmental qualification, predictive maintenance, instrumentation and control, steam generator cleaning, decontamination and radiation protection, inspection techniques, maintenance program strategies and valve packing experience, remote tooling/ robotics and fuel handling. The individual papers have been abstracted separately.

Maintenance, reliability and policies for orbital space station life support systems

International Nuclear Information System (INIS)

Russell, James F.; Klaus, David M.

2007-01-01

The performance of productive work on space missions is critical to sustaining a human presence on orbital space stations (OSS), the Moon, or Mars. Available time for productive work has potentially been impacted on past OSS missions by underestimating the crew time needed to maintain systems, such as the Environmental Control and Life Support System (ECLSS). To determine the cause of this apparent disconnect between the design and operation of an OSS, documented crew time for maintenance was collected from the three Skylab missions and Increments 4-8 on the International Space Station (ISS), and the data was contrasted to terrestrial facility maintenance norms. The results of the ISS analysis showed that for four operational and seven functional categories, the largest deviation of 60.4% over the design time was caused by three of the four operational categories not being quantitatively included in the design documents. In a cross category analysis, 35.3% of the crew time was found to have been used to repair air and waste handling systems. The air system required additional crew time for maintenance due to a greater than expected failure rate and resultant increased time needed for repairs. Therefore, it appears that the disconnect between the design time and actual operations for ECLSS maintenance on ISS was caused by excluding non-repair activities from the estimates and experiencing greater than expected technology maintenance requirements. Based on these ISS and Skylab analyses, future OSS designs (and possibly lunar and Martian missions as well) should consider 3.0-3.3 h/day for crews of 2 to 3 as a baseline of crew time needed for ECLSS maintenance

Development of plant maintenance systems

International Nuclear Information System (INIS)

Tomita, Jinji; Ike, Masae; Nakayama, Kenji; Kato, Hisatomo

1989-01-01

Toshiba is making active efforts for the continuing improvement of reliability and maintainability of operating nuclear power plants. As a part of these efforts, the company has developed new maintenance administration systems, diagnostic monitoring facilities for plant equipments, computer-aided expert systems, and remote-controlled machines for maintenance work. The maintenance administration systems provide efficient work plans and data acquisition capabilities for the management of personnel and equipments involved in nuclear power plant maintenance. The plant diagnostic facilities monitor and diagnose plant conditions for preventive maintenance, as well as enabling rapid countermeasures to be carried out should they be required. Expert systems utilizing artificial intelligence (AI) technology are also employed. The newly developed remote-controlled machines are useful tools for the maintenance inspection of equipment which can not be easily accessed. (author)

Johnson Space Center's Risk and Reliability Analysis Group 2008 Annual Report

Science.gov (United States)

Valentine, Mark; Boyer, Roger; Cross, Bob; Hamlin, Teri; Roelant, Henk; Stewart, Mike; Bigler, Mark; Winter, Scott; Reistle, Bruce; Heydorn,Dick

2009-01-01

The Johnson Space Center (JSC) Safety & Mission Assurance (S&MA) Directorate s Risk and Reliability Analysis Group provides both mathematical and engineering analysis expertise in the areas of Probabilistic Risk Assessment (PRA), Reliability and Maintainability (R&M) analysis, and data collection and analysis. The fundamental goal of this group is to provide National Aeronautics and Space Administration (NASA) decisionmakers with the necessary information to make informed decisions when evaluating personnel, flight hardware, and public safety concerns associated with current operating systems as well as with any future systems. The Analysis Group includes a staff of statistical and reliability experts with valuable backgrounds in the statistical, reliability, and engineering fields. This group includes JSC S&MA Analysis Branch personnel as well as S&MA support services contractors, such as Science Applications International Corporation (SAIC) and SoHaR. The Analysis Group s experience base includes nuclear power (both commercial and navy), manufacturing, Department of Defense, chemical, and shipping industries, as well as significant aerospace experience specifically in the Shuttle, International Space Station (ISS), and Constellation Programs. The Analysis Group partners with project and program offices, other NASA centers, NASA contractors, and universities to provide additional resources or information to the group when performing various analysis tasks. The JSC S&MA Analysis Group is recognized as a leader in risk and reliability analysis within the NASA community. Therefore, the Analysis Group is in high demand to help the Space Shuttle Program (SSP) continue to fly safely, assist in designing the next generation spacecraft for the Constellation Program (CxP), and promote advanced analytical techniques. The Analysis Section s tasks include teaching classes and instituting personnel qualification processes to enhance the professional abilities of our analysts

Integrated maintenance program (IMP)

International Nuclear Information System (INIS)

Zemdegs, R.T.; Chout, Q.B.

1998-01-01

the station's maintenance effectiveness and reduce maintenance costs including RCM4, callup overhauls, analysis of equipment and system failure history to name a few. It has become apparent that there is no single D o-All m aintenance strategy. What is needed is an integrated program combining the benefits of a variety of problem-specific strategies. Such a program should address both the short term and long term station requirements. The impact of the Integrated Maintenance Program (IMP) is expected to be high. In the short term, IMP will upgrade the call-up management system to provide accurate classification, effective monitoring and reporting, and develop a documented rationale (PMO) for each Preventive Maintenance task. To the greatest extent possible, IMP will utilize on-condition (predictive) maintenance and result in the elimination of replacement of many obsolete or ineffective preventive maintenance call-ups. The IMP described in this paper, will improve maintenance effectiveness, equipment reliability and have cost benefits to Ontario Hydro. In doing so it will reduce the cost of maintenance and improve system availability and reliability. (author)

The Maintenance Personnel Performance Simulation (MAPPS) model: A human reliability analysis tool

International Nuclear Information System (INIS)

Knee, H.E.

1985-01-01

The Maintenance Personnel Performance Simulation (MAPPS) model is a computerized, stochastic, task-oriented human behavioral model developed to provide estimates of nuclear power plant (NPP) maintenance team performance measures. It is capable of addressing person-machine, person-environment, and person-person relationships, and accounts for interdependencies that exist between the subelements that make up the maintenance task of interest. The primary measures of performance estimated by MAPPS are: 1) the probability of successfully completing the task of interest and 2) the task duration time. MAPPS also estimates a host of other performance indices, including the probability of an undetected error, identification of the most- and least-likely error-prone subelements, and maintenance team stress profiles during task execution

The development of specific reliability database for a Korean Nuclear Power Plant

International Nuclear Information System (INIS)

Park, S.K.; Park, B.L.; Kim, M.R.; Jeong, B.H.; Kwon, J.J.

2001-01-01

The object of this study is to develop reliability database for PSA application such as failure rate for safety related components, test and maintenance unavailability and common cause failure factors except for initiating event frequencies during the period of 10 years from 1990 to 1999. In this study we developed plant-specific reliability database for PSA (Probabilistic Safety Assessment) application and compared it with generic reliability database developed in the US such as EPRI-URD, IEEE-500, NUCLARR etc, in the component type basis. We have found that there are some general differences in the component failure rate and test and maintenance unavailability. We described the characteristics of differences for some important component types. We also analyzed the reasons for the differences in the aspect of maintenance terms such as maintenance policy and maintenance practice. We found that maintenance terms are important factors for the numbers of plant-specific reliability database. (author)

Integrated maintenance management model in the printing industry

Directory of Open Access Journals (Sweden)

Csaba Horváth

2010-09-01

Full Text Available Rapid technological and economic changes are setting radically new task for maintenance divisions of printingworks. In this dissertation the author provides a summary on the possible approaches for the adoption to the newrequirements. He formulates his situation analysis based on an exhaustive questionnaire survey, and points out thecurrents of changes and challenges caused by the expected developments in the maintenance field of the printingindustry.Based on the possible answers on these challenges, the Author has compiled a - yet missing - maintenance managementmodel that encompasses the maintenance specialties of the industry, as well as the professional heritage andthe latest scientific accomplishments in the discipline of maintenance.The model is based on the widely accepted quality focused maintenance approach, that is supplemented by theAuthor with four new aspects - 1 reliability-focused culture, 2 quality management system, 3 employment ofexternal service provides, 4 maintenance characteristics specific to printing machinery - determining their effectsand integrating them into one single system.In order to construct the model, the Author develops specific solutions that can be seen as own scientific achievementson the specification of maintenance characteristics of printing machinery; on the efficiency improving applicationsof quality management systems, modern knowledge management and reliability focused corporate culture;and on the implementation of a maintenance information system.

Knowledge representation for integrated plant operation and maintenance

DEFF Research Database (Denmark)

Lind, Morten

2010-01-01

Integrated operation and maintenance of process plants has many advantages. One advantage is the improved economy obtained by reducing the number of plant shutdowns. Another is to increase reliability of operation by monitoring of risk levels during on-line maintenance. Integrated plant operation...... and maintenance require knowledge bases which can capture the interactions between the two plant activities. As an example, taking out a component or a subsystem for maintenance during operation will require a knowledge base representing the interactions between plant structure, functions, operating states...... and goals and incorporate knowledge about redundancy and reliability data. Multilevel Flow Modeling can be used build knowledge bases representing plant goals and functions and has been applied for fault diagnosis and supervisory control but currently it does not take into account structural information...

Use of knowledge based systems for rational reliability analysis based inspection and maintenance planning for offshore structures

International Nuclear Information System (INIS)

Tang, M.X.; Dharmavasan, S.; Peers, S.M.C.

1994-01-01

The structural integrity of fixed offshore platforms is ensured by periodic inspections. In the past, decisions made as to when, where and how to inspect have been made by engineers using rules-of-thumb and general planning heuristics. It is now hoped that more rational inspection and maintenance scheduling may be carried out by applying recently developed techniques based on structural reliability methods. However, one of the problems associated with a theoretical approach is that it is not always possible to incorporate all the constraints that are present in a practical situation. These constraints modify the decisions made for analysis data input and the interpretation of the analysis results. Knowledge based systems provide a mean of encapsulating several different forms of information and knowledge within a computer system and hence can overcome this problem. In this paper, a prototype system being developed for integrating reliability based analysis with other constraints for inspection scheduling will be described. In addition, the scheduling model and the algorithms to carry out the scheduling will be explained. Furthermore, implementation details are also given

Estimating the Reliability of Aggregated and Within-Person Centered Scores in Ecological Momentary Assessment

Science.gov (United States)

Huang, Po-Hsien; Weng, Li-Jen

2012-01-01

A procedure for estimating the reliability of test scores in the context of ecological momentary assessment (EMA) was proposed to take into account the characteristics of EMA measures. Two commonly used test scores in EMA were considered: the aggregated score (AGGS) and the within-person centered score (WPCS). Conceptually, AGGS and WPCS represent…

Maintenance of radiation monitoring systems

International Nuclear Information System (INIS)

Aoyama, Kei

2001-01-01

As the safety and quality of atomic power facilities are more strongly required, the reliability improvement and preventive maintenance of radiation monitoring systems are important. This paper describes the maintenance of radiation monitoring systems delivered by Fuji Electric and the present status of preventive maintenance technology. Also it introduces the case that we developed a fault diagnosis function adopting a statistics technique and artificial intelligence (AI) and delivered a radiation monitoring system including this function. This system can output a fault analysis result and a countermeasure from the computer in real time. (author)

Machinery prognostics and prognosis oriented maintenance management

CERN Document Server

Yan, Jihong

2014-01-01

This book gives a complete presentatin of the basic essentials of machinery prognostics and prognosis oriented maintenance management, and takes a look at the cutting-edge discipline of intelligent failure prognosis technologies for condition-based maintenance.  Latest research results and application methods are introduced for signal processing, reliability moelling, deterioration evaluation, residual life prediction and maintenance-optimization as well as applications of these methods.

Experts' meeting: Maintenance '83

International Nuclear Information System (INIS)

1983-01-01

The brochure presents, in full wording, 20 papers read at the experts' meeting ''Maintenance '83'' in Wiesbaden. Most of the papers discuss reliability data (acquisition, evaluation, processing) of nearly all fields of industry. (RW) [de

Joint optimization of production scheduling and machine group preventive maintenance

International Nuclear Information System (INIS)

Xiao, Lei; Song, Sanling; Chen, Xiaohui; Coit, David W.

2016-01-01

Joint optimization models were developed combining group preventive maintenance of a series system and production scheduling. In this paper, we propose a joint optimization model to minimize the total cost including production cost, preventive maintenance cost, minimal repair cost for unexpected failures and tardiness cost. The total cost depends on both the production process and the machine maintenance plan associated with reliability. For the problems addressed in this research, any machine unavailability leads to system downtime. Therefore, it is important to optimize the preventive maintenance of machines because their performance impacts the collective production processing associated with all machines. Too lengthy preventive maintenance intervals may be associated with low scheduled machine maintenance cost, but may incur expensive costs for unplanned failure due to low machine reliability. Alternatively, too frequent preventive maintenance activities may achieve the desired high reliability machines, but unacceptably high scheduled maintenance cost. Additionally, product scheduling plans affect tardiness and maintenance cost. Two results are obtained when solving the problem; the optimal group preventive maintenance interval for machines, and the assignment of each job, including the corresponding start time and completion time. To solve this non-deterministic polynomial-time problem, random keys genetic algorithms are used, and a numerical example is solved to illustrate the proposed model. - Highlights: • Group preventive maintenance (PM) planning and production scheduling are jointed. • Maintenance interval and assignment of jobs are decided by minimizing total cost. • Relationships among system age, PM, job processing time are quantified. • Random keys genetic algorithms (GA) are used to solve the NP-hard problem. • Random keys GA and Particle Swarm Optimization (PSO) are compared.

Equipment Reliability Program in NPP Krsko

International Nuclear Information System (INIS)

Skaler, F.; Djetelic, N.

2006-01-01

Operation that is safe, reliable, effective and acceptable to public is the common message in a mission statement of commercial nuclear power plants (NPPs). To fulfill these goals, nuclear industry, among other areas, has to focus on: 1 Human Performance (HU) and 2 Equipment Reliability (EQ). The performance objective of HU is as follows: The behaviors of all personnel result in safe and reliable station operation. While unwanted human behaviors in operations mostly result directly in the event, the behavior flaws either in the area of maintenance or engineering usually cause decreased equipment reliability. Unsatisfied Human performance leads even the best designed power plants into significant operating events, which can be found as well-known examples in nuclear industry. Equipment reliability is today recognized as the key to success. While the human performance at most NPPs has been improving since the start of WANO / INPO / IAEA evaluations, the open energy market has forced the nuclear plants to reduce production costs and operate more reliably and effectively. The balance between these two (opposite) goals has made equipment reliability even more important for safe, reliable and efficient production. Insisting on on-line operation by ignoring some principles of safety could nowadays in a well-developed safety culture and human performance environment exceed the cost of electricity losses. In last decade the leading USA nuclear companies put a lot of effort to improve equipment reliability primarily based on INPO Equipment Reliability Program AP-913 at their NPP stations. The Equipment Reliability Program is the key program not only for safe and reliable operation, but also for the Life Cycle Management and Aging Management on the way to the nuclear power plant life extension. The purpose of Equipment Reliability process is to identify, organize, integrate and coordinate equipment reliability activities (preventive and predictive maintenance, maintenance

Human Reliability Analysis. Applicability of the HRA-concept in maintenance shutdown

International Nuclear Information System (INIS)

Obenius, Aino

2007-08-01

Probabilistic Safety Analysis (PSA) is performed for Swedish nuclear power plants in order to make predictions and improvements of system safety. The analysis of the Three Mile Island and Chernobyl accidents contributed to broaden the approach to nuclear power plant safety. A system perspective focusing on the interaction between aspects of Man, Technology and Organization (MTO) emerged in addition to the development of Human Factors knowledge. To take the human influence on the technical system into consideration when performing PSAs, a Human Reliability Analysis (HRA) is performed. PSA is performed for different stages and plant operating states, and the current state of Swedish analyses is Low power and Shutdown (LPSD), also called Shutdown PSA (SPSA). The purpose of this master's thesis is to describe methods and basic models used when analysing human reliability for the LPSD state. The following questions are at issue: 1. How can the LPSD state be characterised and defined? 2. What is important to take into consideration when performing a LPSD HRA? 3. How can human behaviour be modelled for a LPSD risk analysis? 4. According to available empirical material, how are the questions above treated in performed analysis of human operation during LPSD? 5. How does the result of the questions above affect the way methods for analysis of LPSD could and/or should be developed? The procedure of this project has mainly consisted of literature studies of available theory for modelling of human behaviour and risk analysis of the LPSD state. This study regards analysis of planned outages when maintenance, fuel change, tests and inspections are performed. The outage period is characterised by planned maintenance activities performed in rotating 3-shifts, around the clock, as well as many of the persons performing work tasks on the plant being external contractors. The working conditions are characterised by stress due to heat, radiation and physically demanding or monotonous

Review of Reliability Assessment of Westinghouse SSPS Using SPC by WEC

International Nuclear Information System (INIS)

Kang, H. T.; Chung, H. Y.

2007-01-01

Westinghouse Electric Company (WEC) has accomplished the reliability assessment of Westinghouse Solid State Protection System (SSPS) in KORI no. 2, 3, 4, and YGN no. 1, 2. In their studies, it is reported that creating a cost-effective plan for improving the reliability of the SSPS and at KORI no. 2, 3 and 4, and YGN no. 1, 2 should be needed while reducing their maintenance cost. In this paper, we reviewed the reliability assessment of Westinghouse SSPS analyzed in two performance standards, availability, and the maintenance expense using Statistic Process Control (SPC). As a result, it is concluded all plants have several failures reported but no effect on the system's availability, and the maintenance expense analysis did not reduce the current maintenance expense by 30%. Therefore, overall review for the reliability assessment is that a new strategy for cost-effective plan and/or upgrade approach for improving the reliability of the aging Westinghouse SSPS should be needed

FAMILY BEHAVIOR IN MAINTENANCE STATUS HB CHRONIC RENAL FAILURE PATIENTS THROUGH FAMILY CENTERED CARE APPROACH OF DIET FE MANAGEMENT

Directory of Open Access Journals (Sweden)

Anggia Fajar Hardianti

2017-04-01

Full Text Available Introduction: Erythropoietic agent as standard practice for anemia treatment, which has a function to increase the value of hemoglobin (Hb to 12 g/dl in patients with chronic renal failure (CRF, who receiving dialysis treatment. The use of erythropoietin has to keep of the iron/Fe amount in the body. Family who have a duty of care should have knowledge, attitude, and behavior to maintain patient’s Hb by giving support to the patient to obey the Fe diet. The aimed of this study was to investigate the effect of family centered care approach in management Fe diet toward family’s behaviour in maintenance Hb level of CRF patients in hemodialysis ward, Gambiran Hospital, Kediri. Method: This study was used a pre experimental design. Total sample were 10 respondents, who met to inclusion criteria. The independent variables were knowledge, attitude, and psychomotor of family in maintenance of Hb level in CRF’s patients. The dependent variable was Fe diet management with family centered care approach. Data was collected by using a structured questionnaire and home visit observation. Result: Data was analyzed by using Wilcoxon Sign Rank Test with significance level α≤0.05. Results showed that Fe diet management with family centered care approach took effect to family’s knowledge (p=0.011, family’s attitude (p=0.005 and family’s psychomotor (p=0.005 in maintenance Hb level of CRF patients. Discussion: Family’s knowledge, attitude, and psychomotor were effected by experiences during the care of a patient, not affordable to access information and patient’s own decision. The strengths and weaknesses in the family to got a better plan of care can be made by discuss and sharing among researcher, patient and his family. It can be concluded that Fe diet management with family centered care approach took effect to family’s behaviour. Further studies should involve larger respondents and better measurement tools to obtain more accurate results.

Reliability data book

International Nuclear Information System (INIS)

Bento, J.P.; Boerje, S.; Ericsson, G.; Hasler, A.; Lyden, C.O.; Wallin, L.; Poern, K.; Aakerlund, O.

1985-01-01

The main objective for the report is to improve failure data for reliability calculations as parts of safety analyses for Swedish nuclear power plants. The work is based primarily on evaluations of failure reports as well as information provided by the operation and maintenance staff of each plant. In the report are presented charts of reliability data for: pumps, valves, control rods/rod drives, electrical components, and instruments. (L.E.)

design of preventive maintenance scheduling model for ...

African Journals Online (AJOL)

connected in parallel, Rj(ti) is the reliability of the jth unit at ith time interval, n is the to- tal number of systems (components or units) connected in parallel. Equations (3) and (4) enable us to deter- mine the reliability of all components, units or sub-systems in an industry. 5. System Reliability with Preventive. Maintenance. Fig.

A PSO approach for preventive maintenance scheduling optimization

International Nuclear Information System (INIS)

Pereira, C.M.N.A.; Lapa, C.M.F.; Mol, A.C.A.; Luz, A.F. da

2009-01-01

This work presents a Particle Swarm Optimization (PSO) approach for preventive maintenance policy optimization, focused in reliability and cost. The probabilistic model for reliability and cost evaluation is developed in such a way that flexible intervals between maintenance are allowed. As PSO is skilled for realcoded continuous spaces, a non-conventional codification has been developed in order to allow PSO to solve scheduling problems (which is discrete) with variable number of maintenance interventions. In order to evaluate the proposed methodology, the High Pressure Injection System (HPIS) of a typical 4-loop PWR has been considered. Results demonstrate ability in finding optimal solutions, for which expert knowledge had to be automatically discovered by PSO. (author)

Determination of Pareto frontier in multi-objective maintenance optimization

International Nuclear Information System (INIS)

Certa, Antonella; Galante, Giacomo; Lupo, Toni; Passannanti, Gianfranco

2011-01-01

The objective of a maintenance policy generally is the global maintenance cost minimization that involves not only the direct costs for both the maintenance actions and the spare parts, but also those ones due to the system stop for preventive maintenance and the downtime for failure. For some operating systems, the failure event can be dangerous so that they are asked to operate assuring a very high reliability level between two consecutive fixed stops. The present paper attempts to individuate the set of elements on which performing maintenance actions so that the system can assure the required reliability level until the next fixed stop for maintenance, minimizing both the global maintenance cost and the total maintenance time. In order to solve the previous constrained multi-objective optimization problem, an effective approach is proposed to obtain the best solutions (that is the Pareto optimal frontier) among which the decision maker will choose the more suitable one. As well known, describing the whole Pareto optimal frontier generally is a troublesome task. The paper proposes an algorithm able to rapidly overcome this problem and its effectiveness is shown by an application to a case study regarding a complex series-parallel system.

Aging management and preventive maintenance for nuclear power plants

International Nuclear Information System (INIS)

Bessho, Toichi; Sagawa, Wataru; Oyamada, Osamu; Uchida, Shunsuke

1995-01-01

It is expected that nuclear power generation will bear main electric power supply for long term. For this purpose, by applying proper preventive maintenance to the nuclear power plants in operation, the maintenance of high reliability and the rate of plant operation is extremely important. Especially it has been strongly demanded to execute efficiently the periodic inspection which is carried out every year to shorten its period and increase the rate of operation, and to maintain the reliability by the proper maintenance for the aged plants with long operation years. As to efficient and short periodic inspection, the preparation is advanced by the guidance of electric power companies aiming at realizing it in nearest fiscal year, and further, effort is exerted for the development of technology in long term to optimize periodic inspection. For securing the reliability of aged plants, it is important to do proper inspection and diagnosis and to take the countermeasures by repair and replacement, based on the grasp of secular change mechanism and the evaluation of life of machinery, equipment and materials. In particular, effort is exerted for the development of maintenance technology for reactor pressure vessels and in-core equipment which are hard to access. The confirmation of the function of remote operation equipment and the establishment of execution condition are carried out by uisng the full scale mock-up of BWR plant. The problems in maintenance service and the activities and results of reliability improvement are reported. (K.I.)

Reliability analysis of safety systems of nuclear power plant and utility experience with reliability safeguarding of systems during specified normal operation

International Nuclear Information System (INIS)

Balfanz, H.P.

1989-01-01

The paper gives an outline of the methods applied for reliability analysis of safety systems in nuclear power plant. The main tasks are to check the system design for detection of weak points, and to find possibilities of optimizing the strategies for inspection, inspection intervals, maintenance periods. Reliability safeguarding measures include the determination and verification of the broundary conditions of the analysis with regard to the reliability parameters and maintenance parameters used in the analysis, and the analysis of data feedback reflecting the plant response during operation. (orig.) [de

Optimization of maintenance policy using the proportional hazard model

Energy Technology Data Exchange (ETDEWEB)

Samrout, M. [Information Sciences and Technologies Institute, University of Technology of Troyes, 10000 Troyes (France)], E-mail: mohamad.el_samrout@utt.fr; Chatelet, E. [Information Sciences and Technologies Institute, University of Technology of Troyes, 10000 Troyes (France)], E-mail: chatelt@utt.fr; Kouta, R. [M3M Laboratory, University of Technology of Belfort Montbeliard (France); Chebbo, N. [Industrial Systems Laboratory, IUT, Lebanese University (Lebanon)

2009-01-15

The evolution of system reliability depends on its structure as well as on the evolution of its components reliability. The latter is a function of component age during a system's operating life. Component aging is strongly affected by maintenance activities performed on the system. In this work, we consider two categories of maintenance activities: corrective maintenance (CM) and preventive maintenance (PM). Maintenance actions are characterized by their ability to reduce this age. PM consists of actions applied on components while they are operating, whereas CM actions occur when the component breaks down. In this paper, we expound a new method to integrate the effect of CM while planning for the PM policy. The proportional hazard function was used as a modeling tool for that purpose. Interesting results were obtained when comparison between policies that take into consideration the CM effect and those that do not is established.

Maintenance Process Strategic Analysis

Science.gov (United States)

Jasiulewicz-Kaczmarek, M.; Stachowiak, A.

2016-08-01

The performance and competitiveness of manufacturing companies is dependent on the availability, reliability and productivity of their production facilities. Low productivity, downtime, and poor machine performance is often linked to inadequate plant maintenance, which in turn can lead to reduced production levels, increasing costs, lost market opportunities, and lower profits. These pressures have given firms worldwide the motivation to explore and embrace proactive maintenance strategies over the traditional reactive firefighting methods. The traditional view of maintenance has shifted into one of an overall view that encompasses Overall Equipment Efficiency, Stakeholders Management and Life Cycle assessment. From practical point of view it requires changes in approach to maintenance represented by managers and changes in actions performed within maintenance area. Managers have to understand that maintenance is not only about repairs and conservations of machines and devices, but also actions striving for more efficient resources management and care for safety and health of employees. The purpose of the work is to present strategic analysis based on SWOT analysis to identify the opportunities and strengths of maintenance process, to benefit from them as much as possible, as well as to identify weaknesses and threats, so that they could be eliminated or minimized.

Design of an operator support system for online maintenance at nuclear power plant

International Nuclear Information System (INIS)

Chu Yongyue; Li Huwei; Gao Qiang; Yi Yan; Yang Ming

2013-01-01

Online maintenance based on reliability centered management is pivotal for the safe and economical operation of Nuclear Power Plant (NPP). This paper presents an operator support system through which the operators can effectively manage plant configuration and identify the weaknesses in plant operation. The proposed operator support system is based on the GO-FLOW, which is a success-oriented availability analysis methodology and can be used for evaluating phased missions. In this paper, the design of the proposed operator support system is introduced through a case study of the Auxiliary Feed Water System (AFWS). (author)

Maintenance Personnel Performance Simulation (MAPPS) model: a human reliability analysis tool

International Nuclear Information System (INIS)

Knee, H.E.

1985-01-01

The Maintenance Personnel Performance Simulation (MAPPS) model is a computerized, stochastic, task-oriented human behavioral model developed to provide estimates of nuclear power plant (NPP) maintenance team performance measures. It is capable of addressing person-machine, person-environment, and person-person relationships, and accounts for interdependencies that exist between the subelements that make up the maintenance task of interest. The primary measures of performance estimated by MAPPS are: (1) the probability of successfully completing the task of interest; and (2) the task duration time. MAPPS also estimates a host of other performance indices, including the probability of an undetected error, identification of the most- and least-likely error-prone subelements, and maintenance team stress profiles during task execution. The MAPPS model was subjected to a number of evaluation efforts that focused upon its practicality, acceptability, usefulness, and validity. Methods used for these efforts included a case method approach, consensus estimation, and comparison with observed task performance measures at a NPP. Favorable results, such as close agreement between task duration times for two tasks observed in the field (67.0 and 119.8 minutes, respectively), and estimates by MAPPS (72.0 and 124.0 minutes, respectively) enhance the confidence in the future use of MAPPS. 8 refs., 1 fig

Mathematical thinking of maintenance. Problem setting and solving bases

International Nuclear Information System (INIS)

2007-01-01

Plant or mechanical facility for maintenance became more complicated than before and consisted of many subsystems made of various equipments or facilities with parts, which were a system having complicated and hierarchical structure. Maintenance was required to be properly implemented to assure reliability of a system for a long period so as for each equipment to play a specified role for a stable operation of plant. Mathematical thinking using probability theory was rational to optimize maintenance action with failure rate function of system or part of equipment. Reliability function, maintainability function and availability of plant and equipment were defined. Unreliability function was called failure time distribution function (F(t)) and failure rate function (λ(t)) was defined as the ratio of failure time density distribution function (dF(t)/dt) to reliability function (1-F(t)). λ(t) could be expressed as a simple equation with Weibull parameter. Availability at steady state was attributed to ratio of average operating time to sum of operating time and maintenance time, i.e. MTBF/(MTBF+MTTR) where MTBF was mean time between failures and MTTR was mean time to repair. Optimization of system risk and maintenance action was encouraged using computational science simulating material degradation. (T. Tanaka)

Space station orbit maintenance

Science.gov (United States)

Kaplan, D. I.; Jones, R. M.

1983-01-01

The orbit maintenance problem is examined for two low-earth-orbiting space station concepts - the large, manned Space Operations Center (SOC) and the smaller, unmanned Science and Applications Space Platform (SASP). Atmospheric drag forces are calculated, and circular orbit altitudes are selected to assure a 90 day decay period in the event of catastrophic propulsion system failure. Several thrusting strategies for orbit maintenance are discussed. Various chemical and electric propulsion systems for orbit maintenance are compared on the basis of propellant resupply requirements, power requirements, Shuttle launch costs, and technology readiness.

Structural Reliability Aspects in Design of Wind Turbines

DEFF Research Database (Denmark)

Sørensen, John Dalsgaard

2007-01-01

Reliability assessment, optimal design and optimal operation and maintenance of wind turbines are an area of significant interest for the fast growing wind turbine industry for sustainable production of energy. Offshore wind turbines in wind farms give special problems due to wake effects inside...... the farm. Reliability analysis and optimization of wind turbines require that the special conditions for wind turbine operation are taken into account. Control of the blades implies load reductions for large wind speeds and parking for high wind speeds. In this paper basic structural failure modes for wind...... turbines are described. Further, aspects are presented related to reliability-based optimization of wind turbines, assessment of optimal reliability level and operation and maintenance....

Tele-maintenance 'intelligent' system for technical plants result management

International Nuclear Information System (INIS)

Concetti, Massimo; Cuccioletta, Roberto; Fedele, Lorenzo; Mercuri, Giampiero

2009-01-01

The management of technical plant for productivity and safety is generally a complex activity, particularly when many plants distributed in the territory are considered (i.e. the more and more frequent case of outsourced plants maintenance by specialized companies), granted quality and cost results are required (i.e. the case of some rather innovative contract solutions) and the technology involved is heterogeneous and innovative (i.e. electro-mechanical plants). In order to efficiently achieve the above aims an 'intelligent' maintenance-management system for the distant monitoring and controlling by a remote control center has been developed. The so-called GrAMS (granted availability management system) system is conceived to give to organizations involved in technical-industrial plants management the possibility to tend to a 'well-known availability' and 'zero-failures' management. In particular, this study deals with the diagnostic aspects and safety level of technical plants (such as elevators, thermo-technical plants, etc.), and with the involvement of ad hoc designed software analysis tools based on neural networks and reliability indicators. Part of the research dealing with the tele-maintenance intelligent system has been financed by the Italian High Institute for Safety (ISPESL) and led to the development of a pre-industrial prototype whose realization and testing is here described

Maintenance philosophy and program at Cernavoda NPP

International Nuclear Information System (INIS)

Bobos, M.; Enciu, G.

1994-01-01

Maintenance plays a key role in ensuring safe and reliable operation. An effective maintenance program should ensure that installed equipment operates when needed and the equipment malfunctions or deficiencies are corrected in time and rarely recur. Maintenance includes not only the activities traditionally associated with identifying or correcting current or potential equipment deficiencies but also extends to supporting technical functions for the conduct of these activities (for example, engineering, technical support, chemistry control, radiological protection, industrial safety and training). The maintenance management program should clearly define the relationship among these supporting groups as it is related to overall plant maintenance and promotes the concept of a successful integrated team effort. (Author)

Maintenance Approaches for Different Production Methods

Directory of Open Access Journals (Sweden)

Mungani, Dzivhuluwani Simon

2013-11-01

Full Text Available Various production methods are used in industry to manufacture or produce a variety of products needed by industry and consumers. The nature of a product determines which production method is most suitable or cost-effective. A continuous process is typically used to produce large volumes of liquids or gases. Batch processing is often used for small volumes, such as pharmaceutical products. This paper discusses a research project to determine the relationship between maintenance approaches and production methods. A survey was done to determine to what extent three maintenance approaches reliability-centred maintenance (RCM, total productive maintenance (TPM, and business-centred maintenance (BCM are used for three different processing methods (continuous process, batch process, and a production line method.

Development of divertor remote maintenance system

Energy Technology Data Exchange (ETDEWEB)

Takeda, Nobukazu; Oka, Kiyoshi; Akou, Kentaro; Takiguchi, Yuji [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1998-04-01

The ITER divertor is categorized as a scheduled maintenance component because of extreme heat and particle loads it is exposed to by plasma. It is also highly activated by 14 MeV neutrons. Reliable remote handling equipment and tools are required for divertor maintenance under intense gamma radiation. To facilitate remote maintenance, the divertor is segmented into 60 cassettes, and each cassette weighing about 25 tons and maintained and replaced through four maintenance ports each 90 degrees. Divertor cassettes must be transported toroidally and radially for replacement through maintenance ports. Remote handling involving cassette movers and carriers for toroidal and radial transport has been developed. Under the ITER R and D program, technology critical to divertor cassette maintenance is being developed jointly by Japan, E.U., and U.S. home teams. This paper summarizes divertor remote maintenance design and the status of technology development by the Japan Home Team. (author)

Development of divertor remote maintenance system

International Nuclear Information System (INIS)

Takeda, Nobukazu; Oka, Kiyoshi; Akou, Kentaro; Takiguchi, Yuji

1998-01-01

The ITER divertor is categorized as a scheduled maintenance component because of extreme heat and particle loads it is exposed to by plasma. It is also highly activated by 14 MeV neutrons. Reliable remote handling equipment and tools are required for divertor maintenance under intense gamma radiation. To facilitate remote maintenance, the divertor is segmented into 60 cassettes, and each cassette weighing about 25 tons and maintained and replaced through four maintenance ports each 90 degrees. Divertor cassettes must be transported toroidally and radially for replacement through maintenance ports. Remote handling involving cassette movers and carriers for toroidal and radial transport has been developed. Under the ITER R and D program, technology critical to divertor cassette maintenance is being developed jointly by Japan, E.U., and U.S. home teams. This paper summarizes divertor remote maintenance design and the status of technology development by the Japan Home Team. (author)

7 CFR 1767.27 - Operation and maintenance expenses.

Science.gov (United States)

2010-01-01

..., DEPARTMENT OF AGRICULTURE (CONTINUED) ACCOUNTING REQUIREMENTS FOR RUS ELECTRIC BORROWERS Uniform System of... Waterways 544Maintenance of Electric Plant 545Maintenance of Miscellaneous Hydraulic Plant Other Power....1Load Dispatch-Reliability 561.2Load Dispatch-Monitor and Operate Transmission System 561.3Load Dispatch...

A process for risk-focused maintenance

International Nuclear Information System (INIS)

Lofgren, E.V.; Cooper, S.E.; Kurth, R.E.; Phillips, L.B.

1991-03-01

This report presents a process for focusing maintenance resources on components that enable nuclear plant systems to perform their essential functions and on components whose failure may initiate challenges to safety systems, so as to have the greatest impact in decreasing risk. The process provides criteria, based on risk, for deciding which components are critical to risk and determining what maintenance activities are required to ensure reliable operation of those risk-critical components. Two approaches are provided for selection of risk-critical components. One approach uses the results of a Probabilistic Risk Assessment (PRA); the other is based on the methodology developed for this report, which has a basis in PRA although it does not use the results of a PRA study. Following identification of risk-critical components, both approaches use a single methodology for determining what maintenance activities are required to ensure reliable operation of the identified components. The report also provides demonstrations of application of the two approaches to selection of risk-critical components and demonstrations of application of the methodology for determining what maintenance activities are required to an active standby safety system, a normally operating system, and passive components. 5 refs., 11 figs., 1 tab

A process for risk-focused maintenance

Energy Technology Data Exchange (ETDEWEB)

Lofgren, E.V.; Cooper, S.E.; Kurth, R.E.; Phillips, L.B. (Science Applications International Corp., McLean, VA (USA))

1991-03-01

This report presents a process for focusing maintenance resources on components that enable nuclear plant systems to perform their essential functions and on components whose failure may initiate challenges to safety systems, so as to have the greatest impact in decreasing risk. The process provides criteria, based on risk, for deciding which components are critical to risk and determining what maintenance activities are required to ensure reliable operation of those risk-critical components. Two approaches are provided for selection of risk-critical components. One approach uses the results of a Probabilistic Risk Assessment (PRA); the other is based on the methodology developed for this report, which has a basis in PRA although it does not use the results of a PRA study. Following identification of risk-critical components, both approaches use a single methodology for determining what maintenance activities are required to ensure reliable operation of the identified components. The report also provides demonstrations of application of the two approaches to selection of risk-critical components and demonstrations of application of the methodology for determining what maintenance activities are required to an active standby safety system, a normally operating system, and passive components. 5 refs., 11 figs., 1 tab.

Equipment Reliability Process in Krsko NPP

International Nuclear Information System (INIS)

Gluhak, M.

2016-01-01

To ensure long-term safe and reliable plant operation, equipment operability and availability must also be ensured by setting a group of processes to be established within the nuclear power plant. Equipment reliability process represents the integration and coordination of important equipment reliability activities into one process, which enables equipment performance and condition monitoring, preventive maintenance activities development, implementation and optimization, continuous improvement of the processes and long term planning. The initiative for introducing systematic approach for equipment reliability assuring came from US nuclear industry guided by INPO (Institute of Nuclear Power Operations) and by participation of several US nuclear utilities. As a result of the initiative, first edition of INPO document AP-913, 'Equipment Reliability Process Description' was issued and it became a basic document for implementation of equipment reliability process for the whole nuclear industry. The scope of equipment reliability process in Krsko NPP consists of following programs: equipment criticality classification, preventive maintenance program, corrective action program, system health reports and long-term investment plan. By implementation, supervision and continuous improvement of those programs, guided by more than thirty years of operating experience, Krsko NPP will continue to be on a track of safe and reliable operation until the end of prolonged life time. (author).

Nuclear Power Plant Preventive Maintenance Scheduling Problem with Fuzziness

International Nuclear Information System (INIS)

Abass, S.A.; Abdallah, A.S.

2013-01-01

Maintenance activity is regarded as the most important key factor for the safety, reliability and economy of a nuclear power plant. Preventive maintenance refers to set of planned activities which include nondestructive testing and periodic inspection as well as maintenance. In this paper, we address the problem of nuclear power plant preventive maintenance scheduling with uncertainty. The uncertainty will be represented by fuzzy parameters. The problem is how to determine the period for which generating units of an electric system should be taken off line for planned preventive maintenance over specific time horizon. Preventive maintenance activity of a nuclear power plant is an important issue as it designed to extend the plant life . It is more required to review the maintenance not only from the view point of safety and reliability but also economy. Preventive maintenance program exists to ensure that nuclear safety significant equipment will function when it is supposed to. Also this problem is extremely important because a failure in a power plant may cause a general breakdown in an electric network. In this paper a mixed integer programming model is used to express this problem. In proposed model power demand is taken as fuzzy parameters. A case study is provided to demonstrate the efficiency of the proposed model.

Study to determine the reliability and validity of a needs-assessment instrument used within the mechanical maintenance field of the nuclear electrical-generating industry

International Nuclear Information System (INIS)

Russell, L.O.

1982-01-01

This study was to determine if task parameter ratings provided by nuclear power plant maintenance mechanics assessed the true task frequency, criticality, and difficulty. This was to measure the data's usefulness as a training needs assessment indicator. A questionnaire entitled Job Task Questionnaire for Maintenance Mechanics was developed and used to collect data from job incumbents. Development was based on plant visits and incumbent interviews. Duties, tasks, parameters, and scales were then compiled to form the questionnaire. The questionnaire was then pilot tested. A random sample was selected from the national population of nuclear power plant maintenance mechanics. This resulted in a sample which was stratified across the job title and random within the job title. The descriptive analysis did not tend to indicate that the mean value of each task parameter provided a true or valid value. The overall conclusion drawn from the data analysis was that the ratings did not provide a substantially valid or reliable indication on which to base task training needs

Evaluations of maintenance effectiveness on unavailability and risk

International Nuclear Information System (INIS)

Vesely, W.E.

1993-01-01

A methodology is presented for quantifying the effectiveness of maintenance on unavailability and on risk. The methodology is based on standard Markov modeling principles. What is new is the application to quantify maintenance effectiveness by explicitly quantifying maintenance benefits as well as maintenance's negative contributions. Maintenance effects are quantified by defining a degraded state for the component in addition to an operational state and a failed state which are usually defined. The maintenance model which is developed is a natural extension of the standard models used in reliability analysis and in Probabilistic Risk Assessments (PRAs). The results which are obtained can be directly used in PRAs. Applications of the methodology are presented by quantifying maintenance effectiveness on component performance and component unavailability for specific maintenance schedules

Different Reliability Assessment Approaches for Wave Energy Converters

DEFF Research Database (Denmark)

Ambühl, Simon; Kramer, Morten Mejlhede; Sørensen, John Dalsgaard

2015-01-01

Reliability assessments are of importance for wave energy converters (WECs) due to the fact that accessibility might be limited in case of failure and maintenance. These failure rates can be adapted by reliability considerations. There are two different approaches to how reliability can...

Maintenance in nuclear production power plants

International Nuclear Information System (INIS)

Lozano, J. M.

2010-01-01

This article highlights the importance and quality of maintenance in the complete phases of development, in a sector which has been often questioned by the public opinion, and that is always subject to national and international standards. The aim of maintenance is to guarantee the production of electric power in a reliable, safe, economic and friendly environmentally way, assuring a long-term production. (Author)

Formulação estratégica da manutenção industrial com base na confiabilidade dos equipamentos Strategic formulation of industrial maintenance supported by equipment's reliability

Directory of Open Access Journals (Sweden)

Miguel Afonso Sellitto

2005-04-01

Full Text Available Este trabalho relata o uso da confiabilidade e da manutenibilidade na formulação de estratégias de manutenção industrial. O método utilizado foi o estudo de dois casos. Inicia-se revisando conceitos ligados a variáveis e processos aleatórios como base para definir conceitos e características de estudos de confiabilidade e de modelagem aplicados na gestão da manutenção industrial. A seguir se descrevem os casos estudados, em que se aplicam técnicas de modelagem de tempos até a falha e até o reparo no estabelecimento de estratégias de manutenção em fábricas do setor metal-mecânico. Com base nos resultados, discute-se o caso, estabelecendo condições para o uso da confiabilidade na formulação estratégica da manutenção, principalmente quanto ao sistema de informações necessárias.This paper reports the use of reliability and maintainability assessments in the strategic formulation of industrial maintenance. The method was a double case study. The paper begins by a theoretical review of related concepts of stochastic variables and processes as a basis to address concepts and features from reliability studies and modeling, suited to use in managing the industrial maintenance. One then describes the two studied cases, in which the reliability techniques were applied, in modeling the times to failure and times to the repair for the sake of settling the strategic formulation of industrial maintenance in metal-mechanic plants. Supported by results, this paper discusses the cases, arising requirements to the use of the reliability, mainly related to the information system.

Reliability and maintainability

International Nuclear Information System (INIS)

1994-01-01

Several communications in this conference are concerned with nuclear plant reliability and maintainability; their titles are: maintenance optimization of stand-by Diesels of 900 MW nuclear power plants; CLAIRE: an event-based simulation tool for software testing; reliability as one important issue within the periodic safety review of nuclear power plants; design of nuclear building ventilation by the means of functional analysis; operation characteristic analysis for a power industry plant park, as a function of influence parameters

Condition-based maintenance effectiveness for series–parallel power generation system—A combined Markovian simulation model

International Nuclear Information System (INIS)

Azadeh, A.; Asadzadeh, S.M.; Salehi, N.; Firoozi, M.

2015-01-01

Condition-based maintenance (CBM) is an increasingly applicable policy in the competitive marketplace as a means of improving equipment reliability and efficiency. Not only has maintenance a close relationship with safety but its costs also make it even more attractive issue for researchers. This study proposes a model to evaluate the effectiveness of CBM policy compared to two other maintenance policies: Corrective Maintenance (CM) and Preventive Maintenance (PM). Maintenance policies are compared through two system performance indicators: reliability and cost. To estimate the reliability and costs of the system, the proposed Markovian discrete-event simulation model is developed under each of these policies. The applicability and usefulness of the proposed Markovian simulation model is illustrated for a series–parallel power generation system. The simulated characteristics of CBM system include its prognostics efficiency to estimate remaining useful life of the equipment. Results show that with an efficient prognostics, CBM policy is an effective strategy compared to other maintenance strategies. - Highlights: • A model is developed to evaluate the effectiveness of CBM policy. • Maintenance policies are compared through reliability and cost. • A Markovian simulation model is developed. • A series–parallel power generation system is considered. • CBM is an effective strategy compared to others

Reliability Assessment and Reliability-Based Inspection and Maintenance of Offshore Wind Turbines

DEFF Research Database (Denmark)

Ramírez, José G. Rangel; Sørensen, John Dalsgaard

2009-01-01

Probabilistic methodologies represent an important tool to identify the suitable strategy to inspect and deal with the deterioration in structures such as offshore wind turbines (OWT). Reliability based methods such as Risk Based Inspection (RBI) planning may represent a proper methodology to opt...

Perancangan Maintenance Management Informastion System untuk Unit Pemadam Kebakaran (Studi Kasus : PERUSAHAAN X

Directory of Open Access Journals (Sweden)

Arief Samuel Gunawan

2017-08-01

Full Text Available Unit Pemadam Kebakaran Perusahaan X merupakan unit kerja yang bertugas melakukan pencegahan dan penanggulangan kebakaran di Perusahaan X. Unit ini dilengkapi dengan peralatan dan perlengkapan kerja, salah satunya yaitu mobil pemadam kebakaran. Salah satu permasalahan yang dihadapi oleh unit ini adalah mobil pemadam kebakaran sering mengalami kerusakan pada saat digunakan. Hal ini disebabkan karena umur komponen yang akan habis dan belum dilakukan penggantian. Umumnya bagian pemeliharaan belum memiliki dokumentasi umur komponen dari setiap mobil pemadam kebakaran. Sehingga petugas pemadam kebakaran tidak dapat mengantisipasi kerusakan yang akan terjadi saat mobil pemadam kebakaran digunakan. Untuk menanggulangi permasalahan tersebut, dikembangkan Maintenance Management Information System (MMIS yang dapat memberikan informasi perkiraan umur komponen mobil. Metode Reliability Centered Maintenance (RCM digunakan pada MMIS untuk menentukan Mean Time To Failure (MTTF. Metode Total Productive Maintenance (TPM juga digunakan pada MMIS untuk merencanakan jadwal pemeliharaan sehingga dapat meminimalisir kerusakan saat mobil digunakan. Untuk mendukung MMIS, diterapkan menu untuk konfigurasi yaitu, data pegawai, inventaris mobil pemadam kebakaran serta inventori suku cadang dan pengadaan barang yang akan berhubungan dengan biaya pemeliharaan.

Regulatory oversight of maintenance activities at nuclear power plants in France

International Nuclear Information System (INIS)

Bouton, J.P.; Lallement, J.

1997-01-01

In France the nuclear safety authority sets out the main safety objectives but the operator remains the first responsible for the NPP safety. During the operation, operators have to demonstrate that the safety level remains the same as defined in the design studies. Maintenance contributes to meet this objective. The French regulation insists on the quality of the safety related components maintenance, especially in the 1984 order. All gap between results and requirements have to be analyzed by operator who provide feedback measures to avoid similar failure to occur. This gap have to be mentioned to regulators. The use of probabilistic safety analysis (PSA) and reliability centered maintenance (RCM) methods is not well developed in France to optimize maintenance. For the French regulatory, the major difficulties in the use of PSA are: The impossibility to detect unanticipated failure mode; the validity of the input data; the validity of model use, based on ''engineering judgement''. For the specific case of passive components inspection, such as the vessel of the primary circuit, the French regulator has already indicated to the operator that the optimization of maintenance by use of PSA cannot be used, for the following reasons: The safety analysis does not take into account the failure of the vessel; unanticipated failure modes have already damaged part of the primary circuit; the use of defense in depth concept requires a systematic detection of any defect on the vessel. (author)

Analyzing maintenance strategies by agent-based simulations: A feasibility study

International Nuclear Information System (INIS)

Kaegi, M.; Mock, R.; Kroeger, W.

2009-01-01

Thoroughly planned and implemented maintenance strategies save time and cost. However, the integration of maintenance work into reliability analysis is difficult as common modeling techniques are often not applicable due to state explosion which calls for restrictive model assumptions and oversimplification. From authors' point of view, agent-based modeling (ABM) of technical and organizational systems is a promising approach to overcome such problems. But since ABM is not well established in reliability analysis its feasibility in this area still has to be demonstrated. For this purpose ABM is compared with Markov chains, namely by analyzing the reliability of a maintained n-unit system with dependent repair events, applying both modeling approaches. Although ABM and Markov chains lead to the same numerical results, the former points out the potentiality of an improved system state handling. This is demonstrated by extending the ABM with operators as additional 'agents' featuring their location (x;y) availability (0;1) and different maintenance strategies. This extension highlights the capability of ABM to analyze complex emergent system behavior and allows a systematic refinement and optimization of the maintenance strategies.

Development of reliability-based safety enhancement technology

International Nuclear Information System (INIS)

Kim, Kil Yoo; Han, Sang Hoon; Jang, Seung Cherl

2002-04-01

This project aims to develop critical technologies and the necessary reliability DB for maximizing the economics in the NPP operation with keeping the safety using the information of the risk (or reliability). For the research goal, firstly the four critical technologies(Risk Informed Tech. Spec. Optimization, Risk Informed Inservice Testing, On-line Maintenance, Maintenance Rule) for RIR and A have been developed. Secondly, KIND (Korea Information System for Nuclear Reliability Data) has been developed. Using KIND, YGN 3,4 and UCN 3,4 component reliability DB have been established. A reactor trip history DB for all NPP in Korea also has been developed and analyzed. Finally, a detailed reliability analysis of RPS/ESFAS for KNSP has been performed. With the result of the analysis, the sensitivity analysis also has been performed to optimize the AOT/STI of tech. spec. A statistical analysis procedure and computer code have been developed for the set point drift analysis

Characteristics and application study of AP1000 NPPs equipment reliability classification method

International Nuclear Information System (INIS)

Guan Gao

2013-01-01

AP1000 nuclear power plant applies an integrated approach to establish equipment reliability classification, which includes probabilistic risk assessment technique, maintenance rule administrative, power production reliability classification and functional equipment group bounding method, and eventually classify equipment reliability into 4 levels. This classification process and result are very different from classical RCM and streamlined RCM. It studied the characteristic of AP1000 equipment reliability classification approach, considered that equipment reliability classification should effectively support maintenance strategy development and work process control, recommended to use a combined RCM method to establish the future equipment reliability program of AP1000 nuclear power plants. (authors)

Maintenance Optimization Schedulingof Electric Power SystemsConsidering Renewable EnergySources

OpenAIRE

Yu, Jia

2015-01-01

Maintenance is crucial in any industry to keep components in a reasonable functionalcondition, especially in electric power system, where maintenance is done so that thefrequency and the duration of a fault can be shortened, thus increasing the availability of acertain component. And the reliability of the whole electric power system can also beimproved. In the many deregulated electricity markets, reliability and economic drivingforces are the two aspects that system operators mainly conside...

MULTI-AGENT APPROACH TO BUILDING AN INTELLIGENT VEHICLE MAINTENANCE AND REPAIR SYSTEM

Directory of Open Access Journals (Sweden)

V. Pavlenko

2017-12-01

Full Text Available To ensure the reliability of the car, early detection and prevention of the occurrence and development of failures is required in order to reduce the costs of maintenance and repair. Multi-agent technologies make it possible to raise the level of technical reliability of cars and minimize the costs of performing repair and maintenance operations.

Problematics of Reliability of Road Rollers

Science.gov (United States)

Stawowiak, Michał; Kuczaj, Mariusz

2018-06-01

This article refers to the reliability of road rollers used in a selected roadworks company. Information on the method of road rollers service and how the service affects the reliability of these rollers is presented. Attention was paid to the process of the implemented maintenance plan with regard to the machine's operational time. The reliability of road rollers was analyzed by determining and interpreting readiness coefficients.

Life management and operational experience feedback - tools to enhance safety and reliability of the NPP

International Nuclear Information System (INIS)

Mach, P.

1997-01-01

Preparation has started of the Temelin power plant centralized equipment database. Principles of reliability centered maintenance are studied, and use of these activities will be made in the Plant Ageing Management Programme. The aims of the Programme are as follows: selection of important components subject to ageing, data collection, determination of dominant stressors, development, selection and validation of ageing evaluation methods, setup of experience feedback, determination of responsibilities, methodologies and strategy, elaboration of programme procedures and documentation, and maintenance of programme flexibility. Pilot studies of component ageing are under way: for the reactor pressure vessel, steam generator, pressurizer, piping, ECCS and cables. The organizational structure of the Operational Experience Feedback system is described, as are the responsibility of staff and sources of information. (M.D.)

Discounted cost model for condition-based maintenance optimization

International Nuclear Information System (INIS)

Weide, J.A.M. van der; Pandey, M.D.; Noortwijk, J.M. van

2010-01-01

This paper presents methods to evaluate the reliability and optimize the maintenance of engineering systems that are damaged by shocks or transients arriving randomly in time and overall degradation is modeled as a cumulative stochastic point process. The paper presents a conceptually clear and comprehensive derivation of formulas for computing the discounted cost associated with a maintenance policy combining both condition-based and age-based criteria for preventive maintenance. The proposed discounted cost model provides a more realistic basis for optimizing the maintenance policies than those based on the asymptotic, non-discounted cost rate criterion.

Plant inspection and maintenance technology

International Nuclear Information System (INIS)

Miyahara, Masatoshi; Kanazawa, Masafumi

1995-01-01

The article reports on information systems and related tools that support routine inspection and preventive maintenance activities, which contribute to safer plant operation and increase plant operating duty. Tools include the Mitsubishi Electric Reliability and Availability Upgrade Program-Nuclear (MELRAP-N), which supports the general evolution of industry operating experiences, periodic component replacement management, management of discontinued and modified components, periodic inspection item management, and periodic inspection workplace management. The article also introduces a comprehensive preventive maintenance management system currently under development. (author)

RFA-based 589-nm guide star lasers for ESO VLT: a paradigm shift in performance, operational simplicity, reliability, and maintenance

Science.gov (United States)

Friedenauer, Axel; Karpov, Vladimir; Wei, Daoping; Hager, Manfred; Ernstberger, Bernhard; Clements, Wallace R. L.; Kaenders, Wilhelm G.

2012-07-01

Large telescopes equipped with adaptive optics require 20-25W CW 589-nm sources with emission linewidths of ~5 MHz. These Guide Star (GS) lasers should also be highly reliable and simple to operate and maintain for many years at the top of a mountain facility. Under contract from ESO, industrial partners TOPTICA and MPBC are nearing completion of the development of GS lasers for the ESO VLT, with delivery of the first of four units scheduled for December 2012. We report on the design and performance of the fully-engineered Pre-Production Unit (PPU), including system reliability/availability analysis, the successfully-concluded qualification testing, long-term component and system level tests and long-term maintenance and support planning. The chosen approach is based on ESO's patented narrow-band Raman Fiber Amplifier (EFRA) technology. A master oscillator signal from a linearly-polarized TOPTICA 20-mW, 1178-nm CW diode laser, with stabilized emission frequency and controllable linewidth up to a few MHz, is amplified in an MPBC polarization-maintaining (PM) RFA pumped by a high-power 1120-nm PM fiber laser. With efficient stimulated Brillouin scattering suppression, an unprecedented 40W of narrow-band RFA output has been obtained. This is then mode-matched into a resonant-cavity doubler with a free-spectral-range matching the sodium D2a to D2b separation, allowing simultaneous generation of an additional frequency component (D2b line) to re-pump the sodium atom electronic population. With this technique, the return flux can be increased without having to resort to electro-optical modulators and without the risk of introducing optical wave front distortions. The demonstrated output powers with doubling efficiencies >80% at 589 nm easily exceed the 20W design goal and require less than 700 W of electrical power. In summary, the fiber-based guide star lasers provide excellent beam quality and are modular, turn-key, maintenance-free, reliable, efficient, and ruggedized

Improvement of plant reliability in PT. Badak LNG plant

International Nuclear Information System (INIS)

Achmad, S.; Somantri, A.

1997-01-01

PT. Badak's LNG sales commitment has been steadily increasing, therefore, there has been more emphasis to improve and maintain the LNG plant reliability. From plant operation historical records, Badak LNG plant experienced a high number of LNG process train trips and down time for 1977 through 1988. The highest annual number of LNG plant trips (50 times) occurred in 1983 and the longest LNG process train down time (1259 train-hours) occurred in 1988. Since 1989, PT. Badak has been able to reduce the number of LNG process train trips and down time significantly. In 1994 the number of LNG process train trips and was 18 times and the longest LNG process train down time was 377 train-hours. This plant reliability improvement was achieved by implementing plant reliability improvement programs beginning with the design of the new facilities and continuing with the maintenance and modification of the existing facilities. To improve reliability of the existing facilities, PT. Badak has been implementing comprehensive maintenance programs, to reduce the frequency and down time of the plant, such as Preventive and Predictive Maintenance as well as procurement material improvement since PT. Badak location is in a remote area. By implementing the comprehensive reliability maintenance, PT. Badak has been able to reduce the LNG process train trips to 18 and down time to 337 train hours in 1994 with the subsequent maintenance cost reduction. The average PT. Badak plant availability from 1985 to 1995 is 94.59%. New facilities were designed according to the established PT. Badak design philosophy, master plan and specification. Design of new facilities was modified to avoid certain problems from past experience. (au)

Maintenance of scientific instruments

International Nuclear Information System (INIS)

Lucero, E.

1986-01-01

During the last years Colombia has increased the use of nuclear techniques, instruments and equipment in ambitious health programs, as well as in research centers, industry and education; this has resulted in numerous maintenance problems. As an alternative solution IAN has established a Central Maintenance Laboratory for nuclear instruments within an International Atomic Energy Agency program for eight Latin American and nine Asian Countries. Established strategies and some results are detailed in this writing

Power electronics reliability analysis.

Energy Technology Data Exchange (ETDEWEB)

Smith, Mark A.; Atcitty, Stanley

2009-12-01

This report provides the DOE and industry with a general process for analyzing power electronics reliability. The analysis can help with understanding the main causes of failures, downtime, and cost and how to reduce them. One approach is to collect field maintenance data and use it directly to calculate reliability metrics related to each cause. Another approach is to model the functional structure of the equipment using a fault tree to derive system reliability from component reliability. Analysis of a fictitious device demonstrates the latter process. Optimization can use the resulting baseline model to decide how to improve reliability and/or lower costs. It is recommended that both electric utilities and equipment manufacturers make provisions to collect and share data in order to lay the groundwork for improving reliability into the future. Reliability analysis helps guide reliability improvements in hardware and software technology including condition monitoring and prognostics and health management.

Parameter Estimation of a Reliability Model of Demand-Caused and Standby-Related Failures of Safety Components Exposed to Degradation by Demand Stress and Ageing That Undergo Imperfect Maintenance

Directory of Open Access Journals (Sweden)

S. Martorell

2017-01-01

Full Text Available One can find many reliability, availability, and maintainability (RAM models proposed in the literature. However, such models become more complex day after day, as there is an attempt to capture equipment performance in a more realistic way, such as, explicitly addressing the effect of component ageing and degradation, surveillance activities, and corrective and preventive maintenance policies. Then, there is a need to fit the best model to real data by estimating the model parameters using an appropriate tool. This problem is not easy to solve in some cases since the number of parameters is large and the available data is scarce. This paper considers two main failure models commonly adopted to represent the probability of failure on demand (PFD of safety equipment: (1 by demand-caused and (2 standby-related failures. It proposes a maximum likelihood estimation (MLE approach for parameter estimation of a reliability model of demand-caused and standby-related failures of safety components exposed to degradation by demand stress and ageing that undergo imperfect maintenance. The case study considers real failure, test, and maintenance data for a typical motor-operated valve in a nuclear power plant. The results of the parameters estimation and the adoption of the best model are discussed.

Optimal Inspection and Maintenance Strategies for Structural Systems

DEFF Research Database (Denmark)

Sommer, A. M.

The aim of this thesis is to give an overview of conventional and optimal reliability-based inspection and maintenance strategies and to examine for specific structures how the cost can be reduced and/or the safety can be improved by using optimal reliability-based inspection strategies....... For structures with several almost similar components it is suggested that individual inspection strategies should be determined for each component or a group of components based on the reliability of the actual component. The benefit of this procedure is assessed in connection with the structures considered....... Furthermore, in relation to the calculations performed the intention is to modify an existing program for determination of optimal inspection strategies. The main purpose of inspection and maintenance of structural systems is to prevent or delay damage or deterioration to protect people, environment...

Development and Testing of the Glenn Research Center Visitor's Center Grid-Tied Photovoltaic Power System

Science.gov (United States)

Eichenberg, Dennis J.

2009-01-01

The NASA Glenn Research Center (GRC) has developed, installed, and tested a 12 kW DC grid-tied photovoltaic (PV) power system at the GRC Visitor s Center. This system utilizes a unique ballast type roof mount for installing the photovoltaic panels on the roof of the Visitor s Center with no alterations or penetrations to the roof. The PV system has generated in excess of 15000 kWh since operation commenced in August 2008. The PV system is providing power to the GRC grid for use by all. Operation of the GRC Visitor s Center PV system has been completely trouble free. A grid-tied PV power system is connected directly to the utility distribution grid. Facility power can be obtained from the utility system as normal. The PV system is synchronized with the utility system to provide power for the facility, and excess power is provided to the utility. The project transfers space technology to terrestrial use via nontraditional partners. GRC personnel glean valuable experience with PV power systems that are directly applicable to various space power systems, and provides valuable space program test data. PV power systems help to reduce harmful emissions and reduce the Nation s dependence on fossil fuels. Power generated by the PV system reduces the GRC utility demand, and the surplus power aids the community. Present global energy concerns reinforce the need for the development of alternative energy systems. Modern PV panels are readily available, reliable, efficient, and economical with a life expectancy of at least 25 years. Modern electronics has been the enabling technology behind grid-tied power systems, making them safe, reliable, efficient, and economical with a life expectancy of at least 25 years. Based upon the success of the GRC Visitor s Center PV system, additional PV power system expansion at GRC is under consideration. The GRC Visitor s Center grid-tied PV power system was successfully designed and developed which served to validate the basic principles

Present status of maintenance in nuclear power stations

International Nuclear Information System (INIS)

Fueki, Kensuke

1982-01-01

For nuclear power stations, the improvement of the rate of facility utilization is indispensable. As its means, the shortening of regular inspection period, the adoption of long term cycle operation, the shortening of plant shutdown period by the improvement of the reliability of installed equipment and so on are conceivable. In this paper, the maintenance techniques in nuclear power stations which constitute the basis of reliability improvement are explained. In nuclear power stations, the use of nuclear fuel, accordingly the existence of radioactivity are the remarkable features. At the time of an accident, the nuclear reaction in a reactor must be stopped, and the excessive heat must be removed. The radioactivity in nuclear fuel must not be released outside. The regular inspection of once a year is provided by the law, and routine tests are performed during normal operation. The check-up by operators also is a part of the safety measures. For the early detection of abnormality, the diagnosis system is developed, and the maintenance techniques during operation are examined for being taken into the safety test and standard. The improvement of reliability is attempted by the redundancy of systems. The activity of quality assurance, the organization for the maintenance of nuclear power stations and maintenance works, and the measures to raise the rate of operation are reported. (Kako, I.)

Maintenance and Outage Management Assessment (MOMA)

International Nuclear Information System (INIS)

2005-01-01

The competitive environment has significant implications for nuclear power plant (NPP) operations, which include, inter alia, the need for efficient use of resources and effective management of plant activities of maintenance and outages. The purpose of NPP maintenance and outages is to allow NPPs to use all those functions necessary for safe and reliable power production by keeping them available and adequate maintenance programme is essential. The maintenance programme covers all preventive and remedial measures, both administrative and technical, necessary to identify and mitigate degradation of a functioning system, structure or component, or restore the design functions of a failed system, structure or component to an acceptable level. In response to the needs of MSs, NPES (Nuclear Power Section, Division of Nuclear Power, IAEA) plans to strengthen its services. NPES services will not only continue to provide its 'traditional' products of publications of nuclear industrial best practices and technical implementation of TC projects on plant maintenance and outage management, but also be expanded to deliver, in a timely manner, technical support missions as requested by MSs for NPPs. One of many services is Maintenance and Outage Management Assessment (MOMA). The NPP can obtain support and assistance in assessment and optimisation of its maintenance program and/or outage management. It aims to help the NPP improve its performance of maintenance and outage in a competitive nuclear power business environment. The specific benefits of the assessment are as follows: a) disseminate nuclear industrial best practices on maintenance program and outage management in the world, b) benchmark, evaluate and optimise the approach of maintenance program and outage management and c) identify solutions to known problems at nuclear power plants, if any. MOMA is conducted at the request of NPPs of any IAEA Member States. MOMA consists in a technical mission/visit for 1-3 weeks by

Capacity and reliability analyses with applications to power quality

Science.gov (United States)

Azam, Mohammad; Tu, Fang; Shlapak, Yuri; Kirubarajan, Thiagalingam; Pattipati, Krishna R.; Karanam, Rajaiah

2001-07-01

The deregulation of energy markets, the ongoing advances in communication networks, the proliferation of intelligent metering and protective power devices, and the standardization of software/hardware interfaces are creating a dramatic shift in the way facilities acquire and utilize information about their power usage. The currently available power management systems gather a vast amount of information in the form of power usage, voltages, currents, and their time-dependent waveforms from a variety of devices (for example, circuit breakers, transformers, energy and power quality meters, protective relays, programmable logic controllers, motor control centers). What is lacking is an information processing and decision support infrastructure to harness this voluminous information into usable operational and management knowledge to handle the health of their equipment and power quality, minimize downtime and outages, and to optimize operations to improve productivity. This paper considers the problem of evaluating the capacity and reliability analyses of power systems with very high availability requirements (e.g., systems providing energy to data centers and communication networks with desired availability of up to 0.9999999). The real-time capacity and margin analysis helps operators to plan for additional loads and to schedule repair/replacement activities. The reliability analysis, based on computationally efficient sum of disjoint products, enables analysts to decide the optimum levels of redundancy, aids operators in prioritizing the maintenance options for a given budget and monitoring the system for capacity margin. The resulting analytical and software tool is demonstrated on a sample data center.

Reliability database development and plant performance improvement effort at Korea Hydro and Nuclear Power Co

International Nuclear Information System (INIS)

Oh, S. J.; Hwang, S. W.; Na, J. H.; Lim, H. S.

2008-01-01

Nuclear utilities in recent years have focused on improved plant performance and equipment reliability. In U.S., there is a movement toward process integration. Examples are INPO AP-913 equipment reliability program and the standard nuclear performance model developed by NEI. Synergistic effect from an integrated approach can be far greater than as compared to individual effects from each program. In Korea, PSA for all Korean NPPs (Nuclear Power Plants) has been completed. Plant performance monitoring and improvement is an important goal for KHNP (Korea Hydro and Nuclear Power Company) and a risk monitoring system called RIMS has been developed for all nuclear plants. KHNP is in the process of voluntarily implementing maintenance rule program similar to that in U.S. In the future, KHNP would like to expand the effort to equipment reliability program and to achieve highest equipment reliability and improved plant performance. For improving equipment reliability, the current trend is moving toward preventive/predictive maintenance from corrective maintenance. With the emphasis on preventive maintenance, the failure cause and operation history and environment are important. Hence, the development of accurate reliability database is necessary. Furthermore, the database should be updated regularly and maintained as a living program to reflect the current status of equipment reliability. This paper examines the development of reliability database system and its application of maintenance optimization or Risk Informed Application (RIA). (authors)

Maintenance Optimization of High Voltage Substation Model

Directory of Open Access Journals (Sweden)

Radim Bris

2008-01-01

Full Text Available The real system from practice is selected for optimization purpose in this paper. We describe the real scheme of a high voltage (HV substation in different work states. Model scheme of the HV substation 22 kV is demonstrated within the paper. The scheme serves as input model scheme for the maintenance optimization. The input reliability and cost parameters of all components are given: the preventive and corrective maintenance costs, the actual maintenance period (being optimized, the failure rate and mean time to repair - MTTR.

76 FR 23801 - North American Electric Reliability Corporation; Order Approving Reliability Standard

Science.gov (United States)

2011-04-28

... have an operating plan and facilities for backup functionality to ensure Bulk-Power System reliability... entity's primary control center on the reliability of the Bulk-Power System. \\1\\ Mandatory Reliability... potential impact of a violation of the Requirement on the reliability of the Bulk-Power System. The...

Low-complexity Behavioral Model for Predictive Maintenance of Railway Turnouts

DEFF Research Database (Denmark)

Barkhordari, Pegah; Galeazzi, Roberto; Tejada, Alejandro de Miguel

2017-01-01

Maintenance of railway infrastructures represents a major cost driver for any infrastructure manager since reliability and dependability must be guaranteed at all times. Implementation of predictive maintenance policies relies on the availability of condition monitoring systems able to assess...

Multi-level predictive maintenance for multi-component systems

International Nuclear Information System (INIS)

Nguyen, Kim-Anh; Do, Phuc; Grall, Antoine

2015-01-01

In this paper, a novel predictive maintenance policy with multi-level decision-making is proposed for multi-component system with complex structure. The main idea is to propose a decision-making process considered on two levels: system level and component one. The goal of the decision rules at the system level is to address if preventive maintenance actions are needed regarding the predictive reliability of the system. At component level the decision rules aim at identifying optimally a group of several components to be preventively maintained when preventive maintenance is trigged due to the system level decision. Selecting optimal components is based on a cost-based group improvement factor taking into account the predictive reliability of the components, the economic dependencies as well as the location of the components in the system. Moreover, a cost model is developed to find the optimal maintenance decision variables. A 14-component system is finally introduced to illustrate the use and the performance of the proposed predictive maintenance policy. Different sensitivity analysis are also investigated and discussed. Indeed, the proposed policy provides more flexibility in maintenance decision-making for complex structure systems, hence leading to significant profits in terms of maintenance cost when compared with existing policies. - Highlights: • A predictive maintenance policy for complex structure systems is proposed. • Multi-level decision process based on prognostic results is proposed. • A cost-based group importance measure is introduced for decision-making. • Both positive and negative dependencies between components are investigated. • A cost model and Monte Carlo simulation are developed for optimization process.

Optimization of photovoltaic maintenance plan by means of a FMEA approach based on real data

International Nuclear Information System (INIS)

Villarini, Mauro; Cesarotti, Vittorio; Alfonsi, Lucrezia; Introna, Vito

2017-01-01

Highlights: • Application of RCM, based on FMEA, to photovoltaic systems. • MBS and FMEA determine RPN. • New maintenance plan aimed to reduce fixed RPN of criticalities. • Lower values of RPN by FMEA and major reliability of system obtained. - Abstract: There have been many scientific advances in the improvement of renewable energy systems. Recently, considerable interest has been given to their optimized management during their service life due to a large increase in the number of new renewable energy source power plants. High reliability levels are as important as high yields in order to maximize the useful green energy produced. Solar energy has been one of the most popular and exploited renewable sources in the market and therefore improvements in its efficiency and reliability have had a considerable impact. All energy systems require an increase in their conversion efficiency to reduce the consumption of primary energy. Moreover, the optimization of the performance of photovoltaic systems has increased their incidence as renewable sources in global power generation and has boosted their profitability. A failure of the components and sub-components of a working energy system cause two main issues; the first direct implication for the plant is the damage of the components and sub-components, and the second indirect implication is the consequent lack of energy production due to the plant being out of order. Furthermore, unforeseen failures of the components increase the uncontrollability of photovoltaic power systems, which worsens electric grid dispatching. The work presented here provides, for the first time, a complete and new assessment of Reliability Centered Maintenance carried out using a failure mode and effect analysis approach to photovoltaic systems. We use a large volume of data derived from a database of real maintenance activities carried out by a multinational company. These data were interpreted by the opinions of experts with specialist

A basic condition-based maintenance strategy for air-cooled turbine generators

International Nuclear Information System (INIS)

Laird, T.; Griffith, G.; Hoof, M.

2005-01-01

This paper discusses the methods of using condition-based maintenance (CBM) for turbine generators. Even though it is focused on the maintenance strategy for air-cooled generators, all types of power producers can realize benefits from a better maintenance strategy at lower costs. A reliable assessment of the actual unit condition requires detailed knowledge of the unit design, operational weaknesses, cost of maintenance and operational capabilities. (author)

Rol del fallo mecánico en la optimización del mantenimiento en una central nuclear//Role of the mechanical failure during the maintenance optimization in the nuclear power plant

Directory of Open Access Journals (Sweden)

Antonio Torres-Valle

2012-05-01

Full Text Available Entre las más recientes aplicaciones del Análisis Probabilista de Seguridad (1997 – 2003 de la Central Nuclear Embalse en Argentina, está el Programa de Mantenimiento Orientado a la Seguridad (2006– 2009 el cual se ha desarrollado con el empleo de la metodología de Mantenimiento Centrado en la Confiabilidad (RCM en inglés. El objetivo general del artículo es demostrar la alta contribución de los fallos mecánicos en el diseño de las políticas de mantenimiento de varios sistemas de la instalación a través del empleo de la metodología RCM. La composición, estructura y políticas de explotación de los sistemas tecnológicos de muchas instalaciones con riesgo asociado, similares a las de los sistemas analizados en este estudio, permite inferir que los resultados que se obtendrán serán equivalentes de aplicarse la metodología RCM en dichas instalaciones. Palabras claves: mantenimiento centrado en la confiabilidad, mantenimiento predictivo, mantenimiento preventivo, fallo mecánico, seguridad, confiabilidad, riesgo.______________________________________________________________________________ Abstract One of the most recent applications of Probabilistic Safety Analysis (1997 – 2003 to Embalse Nuclear Power Plant in Argentina, is the Safety Oriented Maintenance Program (2006 – 2009 developed with employment of the Reliability Centered Maintenance (RCM methodology. The general objective of the paper is to demonstrate the high contribution of the mechanical failures in the maintenance program design through the RCM methodology. The composition, structure and operation strategies of the technological systems of many risk associated facilities, similar to the analysed systems included in this study, allow deduce that the results will equivalent in case of application of RCM methodology in such facilities. Key words: reliability centered maintenance (RCM, predictive maintenance, preventive maintenance, mechanical failure, safety

TOP 01-1-011B Vehicle Test Facilities at Aberdeen Test Center and Yuma Test Center

Science.gov (United States)

2017-12-12

Test Center 400 Colleran Road Aberdeen Proving Ground, MD 21005-5059 U.S. Army Yuma Proving Ground Yuma Test Center 301 C. Street Yuma, AZ...22 2.6 Munson Test Area (MTA) ..................................................... 24 2.7 Land Vehicle Maintenance Facility...127 3.6 Maintenance Facilities ........................................................... 143

Ageing model considering effects of maintenance and working conditions

International Nuclear Information System (INIS)

Martorell, S.; Sanchez, A.; Serradell, V.

1998-01-01

Nowadays, there is some doubt about building new Nuclear Power Plants (NPPs). Instead, there is a growing interest in analyzing the possibility to extend current NPP operation where life management programs play an important role. The evolution of the NPP safety depends on the evolution of the reliability of its safety components as a function of their age along the NPP operational life. In this paper, a new age-dependent reliability model is presented, which includes parameters related to surveillance and maintenance effectiveness and working conditions, both environmental and operational, of the equipment. This model may be used to support NPP life management and life extension programs by improving or optimizing surveillance and maintenance tasks using risk and cost models based on such an age-dependent reliability model. The results of the sensitivity study in the application show that the selection of the most appropriate maintenance strategy would directly depend on the previous parameters and very important differences are expected to appear under certain circumstance. (Author) 7 refs

The Centralized Reliability Data Organization (CREDO); an advanced nuclear reactor reliability, availability, and maintainability data bank and data analysis center

International Nuclear Information System (INIS)

Knee, H.E.

1991-01-01

The Centralized Reliability Data Organization (CREDO) is a data bank and data analysis center, which since 1985 has been jointly sponsored by the US Department of Energy's (US DOE's) Office of Technology Support Programs and Japan's Power Reactor and Nuclear Fuel Development Corporation (PNC). It focuses on reliability, availability and maintainability (RAM) data for components (e.g. valves, pumps, etc.) operating in advanced nuclear reactor facilities. As originally intended, the purpose of the CREDO system was to provide a centralized source of accurate, up-to-date data and information for use in RAM analyses necessary for meeting DOE's data needs in the areas of advanced reactor safety assessments, design and licensing. In particular, creation of the CREDO system was considered an essential element needed to fulfill the DOE Breeder Reactor Safety Program's commitment of 'identifying and exploiting areas in which probabilistic methods can be developed and used in making reactor safety Research and Development choices and optimizing designs of safety systems'. CREDO and its operation are explained. (author)

Component aging illustrated in maintenance histories from IPRDS

International Nuclear Information System (INIS)

Kahl, W.K.; Borkowski, R.J.

1984-01-01

The centerpiece of the In-Plant Reliability Data (IPRD) program is a nuclear power plant component data base developed from corrective maintenance records. The primary objective of this program is to establish a comprehensive source of information for reliability analyses, including the compilation of maintenance histories for failure statistics. The IPRD program is currently a pilot effort that has 36 reactor-years of data on pumps, valves, diesel generators, batteries, battery chargers and inverters from five nuclear plants. The data are collected under the auspices of the Institute of Electrical and Electronics Engineers (IEEE) to certify anonymity of the participating plants, and is funded by the Nuclear Regulatory Commission

Design for reliability: NASA reliability preferred practices for design and test

Science.gov (United States)

Lalli, Vincent R.

1994-01-01

This tutorial summarizes reliability experience from both NASA and industry and reflects engineering practices that support current and future civil space programs. These practices were collected from various NASA field centers and were reviewed by a committee of senior technical representatives from the participating centers (members are listed at the end). The material for this tutorial was taken from the publication issued by the NASA Reliability and Maintainability Steering Committee (NASA Reliability Preferred Practices for Design and Test. NASA TM-4322, 1991). Reliability must be an integral part of the systems engineering process. Although both disciplines must be weighed equally with other technical and programmatic demands, the application of sound reliability principles will be the key to the effectiveness and affordability of America's space program. Our space programs have shown that reliability efforts must focus on the design characteristics that affect the frequency of failure. Herein, we emphasize that these identified design characteristics must be controlled by applying conservative engineering principles.

Improvement of AC motor reliability from technique standardization

International Nuclear Information System (INIS)

Muniz, P.R.; Faria, M.D.R.; Mendes, M.P.; Silva, J.N.; Dos Santos, J.D.

2005-01-01

The purpose of this paper is to explain the increase of reliability of motors serviced in the Electrical Maintenance Shop of Companhia Siderurgica de Tubarao by standardization of the technique based on Brazilian and International Standards, manufacturer's recommendations and the experience of the maintenance staff. (author)

On the Use of Time-Limited Information for Maintenance Decision Support: A Predictive Approach under Maintenance Constraints

Directory of Open Access Journals (Sweden)

E. Khoury

2013-01-01

Full Text Available This paper deals with a gradually deteriorating system operating under an uncertain environment whose state is only known on a finite rolling horizon. As such, the system is subject to constraints. Maintenance actions can only be planned at imposed times called maintenance opportunities that are available on a limited visibility horizon. This system can, for example, be a commercial vehicle with a monitored critical component that can be maintained only in some specific workshops. Based on the considered system, we aim to use the monitoring data and the time-limited information for maintenance decision support in order to reduce its costs. We propose two predictive maintenance policies based, respectively, on cost and reliability criteria. Classical age-based and condition-based policies are considered as benchmarks. The performance assessment shows the value of the different types of information and the best way to use them in maintenance decision making.

The application of manipulator robot for nuclear plant maintenance

International Nuclear Information System (INIS)

Kohata, Yukifumi; Fujita, Jun; Onishi, Ken; Tsuhari, Hiroyuki; Hosoe, Fumihiro

2010-01-01

In the maintenance works at nuclear power plant, robots are used because of high radiation, narrow space and underwater work. Various robots are needed because there is various maintenance works. This is inefficiency. As the solutions, we developed manipulator robots for the access of specialized tools. This study shows manipulator robots developed by MHI, application example to maintenance works and effectiveness of manipulator robots. When robotization of maintenance works are considered, manipulator technology is very effective solution means. We achieved efficiency improvement and the reliability improvement by developing a high generality manipulator. (author)

Identification of Optimal Preventive Maintenance Decisions for Composite Components

NARCIS (Netherlands)

Laks, P.; Verhagen, W.J.C.; Gherman, B.; Porumbel, I.

2018-01-01

This research proposes a decision support tool which identifies cost-optimal maintenance decisions for a given planning period. Simultaneously, the reliability state of the component is kept at or below a given reliability threshold: a failure limit policy applies. The tool is developed to support

A generic Approach for Reliability Predictions considering non-uniformly Deterioration Behaviour

International Nuclear Information System (INIS)

Krause, Jakob; Kabitzsch, Klaus

2012-01-01

Predictive maintenance offers the possibility to prognosticate the remaining time until a maintenance action of a machine has to be scheduled. Unfortunately, current predictive maintenance solutions are only suitable for very specific use cases like reliability predictions based on vibration monitoring. Furthermore, they do not consider the fact that machines may deteriorate non-uniformly, depending on external influences (e.g., the work piece material in a milling machine or the changing fruit acid concentration in a bottling plant). In this paper two concepts for a generic predictive maintenance solution which also considers non-uniformly aging behaviour are introduced. The first concept is based on system models representing the health state of a technical system. As these models are usually statically (viz. without a timely dimension) their coefficients are determined periodically and the resulting time series is used as aging indicator. The second concept focuses on external influences (contexts) which change the behaviour of the previous mentioned aging indicators in order to increase the accuracy of reliability predictions. Therefore, context-depended time series models are determined and used to predict machine reliability. Both concepts were evaluated on data of an air ventilation system. Thereby, it could be shown that they are suitable to determine aging indicators in a generic way and to incorporate external influences in the reliability prediction. Through this, the quality of reliability predictions can be significantly increased. In reality this leads to a more accurate scheduling of maintenance actions. Furthermore, the generic character of the solutions makes the concepts suitable for a wide range of aging processes.

Condition-based dynamic maintenance operations planning and grouping. Application to commercial heavy vehicles

Energy Technology Data Exchange (ETDEWEB)

Bouvard, K., E-mail: keomany.bouvard@volvo.co [Volvo Technology, 99 route de Lyon, 69806 Saint Priest cedex (France); Laboratoire d' Automatique de Genie Informatique et Signal - FRE3303 - Polytech' Lille, 59655 Villeneuve d' Ascq (France); Artus, S., E-mail: samuel.artus@volvo.co [Volvo Technology, 99 route de Lyon, 69806 Saint Priest cedex (France); Berenguer, C., E-mail: christophe.berenguer@utt.f [Universite de technologie de Troyes - Institut Charles Delaunay and UMR CNRS 6279 - 12, rue Marie Curie, BP2060, 10010 Troyes cedex (France); Cocquempot, V., E-mail: vincent.cocquempot@univ-lille1.f [Laboratoire d' Automatique de Genie Informatique et Signal - FRE3303 - Polytech' Lille, 59655 Villeneuve d' Ascq (France)

2011-06-15

This paper aims at presenting a method to optimize the maintenance planning for a commercial heavy vehicle. Such a vehicle may be considered as a multi-components system. Grouping maintenance operations related to each component reduces the global maintenance cost of the system. Classically, the optimization problem is solved using a priori reliability characteristics of components. Two types of methods may be used, i.e. static or dynamic methods. Static methods provide a fixed maintenance planning, whereas dynamic methods redefine the groups of maintenance operations at each decision time. Dynamic procedures can incorporate component information such as component states or detected failures. For deteriorating systems, reliability characteristics of each component may be estimated thanks to deterioration models and may be updated when a degradation measure is available. This additional information on degradation features allows to better follow the real state of each component and to improve the maintenance planning.

8th International conference on CANDU maintenance. Conference proceedings

International Nuclear Information System (INIS)

2008-01-01

The 8th International Conference on CANDU Maintenance was held in Toronto, Ontario, Canada on November 16-18, 2008. The theme of the conference was operational excellence: achieving competent, tightly-managed support services and was of interest to people working on the front lines of operations, maintenance and refurbishment. Equipment reliability is a critical factor in achieving safe and reliable Nuclear Power Plant operations for many reasons. For one it reduces the challenges upon the operating staff and allows station personnel to 'go on the offence' instead of having to play defense in a reactive mode. Plant reliability ensures that there is time to study the issues in detail and develop solutions for long-term success. Let us not forget that the owner carries the burden of demonstrating the return on investment, and plant reliability goes a long way in helping to make the case for plant life extension. A good reputation for plant reliability provides the public capital necessary to build confidence and facilitate the licensing process.

Dynamic reliability networks with self-healing units

International Nuclear Information System (INIS)

Jenab, K.; Seyed Hosseini, S.M.; Dhillon, B.S.

2008-01-01

This paper presents an analytical approach for dynamic reliability networks used for the failure limit strategy in maintenance optimization. The proposed approach utilizes the moment generating function (MGF) and the flow-graph concept to depict the functional and reliability diagrams of the system comprised of series, parallel or mix configuration of self-healing units. The self-healing unit is featured by the embedded failure detection and recovery mechanisms presented by self-loop in flow-graph networks. The newly developed analytical approach provides the probability of the system failure and time-to-failure data i.e., mean and standard deviation time-to-failure used for maintenance optimization

Integration of infrared thermography into various maintenance methodologies

Science.gov (United States)

Morgan, William T.

1993-04-01

Maintenance methodologies are in developmental stages throughout the world as global competitiveness drives all industries to improve operational efficiencies. Rapid progress in technical advancements has added an additional strain on maintenance organizations to progressively change. Accompanying needs for advanced training and documentation is the demand for utilization of various analytical instruments and quantitative methods. Infrared thermography is one of the primary elements of engineered approaches to maintenance. Current maintenance methodologies can be divided into six categories; Routine ('Breakdown'), Preventive, Predictive, Proactive, Reliability-Based, and Total Productive (TPM) maintenance. Each of these methodologies have distinctive approaches to achieving improved operational efficiencies. Popular though is that infrared thermography is a Predictive maintenance tool. While this is true, it is also true that it can be effectively integrated into each of the maintenance methodologies for achieving desired results. The six maintenance strategies will be defined. Infrared applications integrated into each will be composed in tabular form.

Practical Maintenance of Digital Systems: Guidance to Maximize the Benefits of Digital Technology for the Maintenance of Digital Systems and Plant Equipment

Energy Technology Data Exchange (ETDEWEB)

Hill, D; Scarola, K

2004-10-30

This report presents detailed guidance for the maintenance and testing of modern digital systems. The guidance provides practical means for plants to take advantage of the increased diagnostic and self-test capabilities of these systems. It helps plants avoid mistakes in design and installation that could lead to increased maintenance burden and decreased system reliability and availability.

Practical Maintenance of Digital Systems. Guidance to Maximize the Benefits of Digital Technology for the Maintenance of Digital Systems and Plant Equipment

International Nuclear Information System (INIS)

Hill, D.; Scarola, K.

2004-01-01

This report presents detailed guidance for the maintenance and testing of modern digital systems. The guidance provides practical means for plants to take advantage of the increased diagnostic and self-test capabilities of these systems. It helps plants avoid mistakes in design and installation that could lead to increased maintenance burden and decreased system reliability and availability

Risk-based maintenance-Techniques and applications

International Nuclear Information System (INIS)

Arunraj, N.S.; Maiti, J.

2007-01-01

Plant and equipment, however well designed, will not remain safe or reliable if it is not maintained. The general objective of the maintenance process is to make use of the knowledge of failures and accidents to achieve the possible safety with the lowest possible cost. The concept of risk-based maintenance was developed to inspect the high-risk components usually with greater frequency and thoroughness and to maintain in a greater manner, to achieve tolerable risk criteria. Risk-based maintenance methodology provides a tool for maintenance planning and decision making to reduce the probability of failure of equipment and the consequences of failure. In this paper, the risk analysis and risk-based maintenance methodologies were identified and classified into suitable classes. The factors affecting the quality of risk analysis were identified and analyzed. The applications, input data and output data were studied to understand their functioning and efficiency. The review showed that there is no unique way to perform risk analysis and risk-based maintenance. The use of suitable techniques and methodologies, careful investigation during the risk analysis phase, and its detailed and structured results are necessary to make proper risk-based maintenance decisions

Electric motor predictive and preventive maintenance guide

International Nuclear Information System (INIS)

Oliver, J.A.

1992-07-01

Electric motor performance is vital to the reliable and efficient operation of power plants. The failure of one or more critical motors could cause lost capacity and excessive repair and maintenance cost. However, existing maintenance recommendations proposed by vendors for electric motors have sometimes encouraged many overly conservative maintenance practices. These practices have lead to excessive maintenance activities and costs which have provided no extra margin of operability. EPRI has sponsored RP2814-35 to develop a guide which provides power plants with information and guidance for establishing an effective maintenance program which will aid in preventing unexpected motor failures and assist in planning motor maintenance efforts. The guide includes a technical description which summarizes technical data relative to the four basic types of motors and their components in general use in power plants. The significant causes of motor failures are investigated and described in detail and methods to optimize service life and minimize maintenance cost through appropriate preventive maintenance and conditioning program are presented. This guide provides a foundation for an effective electric motor maintenance program and simplifies the selection of predictive and preventive maintenance tasks. Its use will enable maintenance personnel in nuclear and fossil plants to plan motor repairs during scheduled outages and avoid costly unexpected failures

Maintenance policy of the nuclear park

International Nuclear Information System (INIS)

Teisset, J.M.

1995-01-01

The nuclear installations maintenance policy of Electricite de France (EDF) follows three axes: first, controlling the aging of the production tool to warrant the safety and the functional reliability during the 40 years of installations service life. Second: optimizing the maintenance activities taking into account the safety goals, costs, security, dosimetry, duration of outages, and intervention conditions in the decisions. Third: developing a real partnership with contractors. EDF has decided to decentralize its maintenance operations towards each unit which is in charge of the organization of its own project. A better management of the contractor personnel has allowed to increase the performances of maintenance operations. The development of long-term agreements with contractors has permitted to reinforce the qualification, the responsibility and the efficiency of the personnel and to improve their means and tools. (J.S.). 1 photo

South Blackwater Coal`s maintenance program

Energy Technology Data Exchange (ETDEWEB)

Nash, J. [South Blackwater Coal Limited, Blackwater, Qld. (Australia)

1998-09-01

The South Blackwater operation consists of two opencut mining areas and two underground mines (Laleham and Kenmure) near Blackwater in central Queensland, all of which supply coal to a central coal preparation plant. South Blackwater Coal Ltd. recently developed a maintenance improvement programme, described in this article. The programme involved implementation systems of key performance indicators (KPIs), benchmaking, condition monitoring, work planning and control, failure analysis and maintenance audit. Some improvements became almost immediately apparent, others were quite gradual. Major results included: improved availability (and reliability) of all opencast fleets, improvements in rear dump availability; reduced maintenance man-hours for opencast fleets; and increased availability of the coal handling and preparation plant. The paper is an edited version of that presented at the `Maintenance in mining conference` 16-19 March 1998, held in Bali, Indonesia. 4 figs., 2 photos.

Reliability Analysis of Fatigue Fracture of Wind Turbine Drivetrain Components

DEFF Research Database (Denmark)

Berzonskis, Arvydas; Sørensen, John Dalsgaard

2016-01-01

in the volume of the casted ductile iron main shaft, on the reliability of the component. The probabilistic reliability analysis conducted is based on fracture mechanics models. Additionally, the utilization of the probabilistic reliability for operation and maintenance planning and quality control is discussed....

Development of optical fiber cable's inspection technology and maintenance criteria

International Nuclear Information System (INIS)

Kim, Min-Su; Ju, Hee-Wan; Shim, Seon-Heum; Lee, Youn-Ki; Kim, Jin-Il; Huh, Tae-Young

2008-01-01

Improve the reliability and establish the systematic maintenance methods for the digital control facilities' optical fiber cable, reviewed the technical requirements and the current maintenance procedures, analyzed the optical fiber cable's characteristics through actual test like bending, tension, attenuation. Based on the results of review, test and analysis, prepared the maintenance criteria and standard maintenance guideline. Also we verified those can be applied directly to the operating nuclear power plant through the actual test at Ulchin Unit 6. The details of test and analysis are presented in this paper. Also introduce the contents of maintenance criteria and guidelines

The right maintenance on the right components, at the right time, with the right parts: maintaining high plant reliability through an effective maintenance program

International Nuclear Information System (INIS)

Von Hatten, P.

2008-01-01

The objective of the maintenance program at a Nuclear Power Plant is to be proactive and prevent unexpected failures of equipment that can impact on Nuclear or Conventional Safety and Plant Production. This does not mean that all equipment failures will be prevented; in a number of cases the most cost effective solution is to allow equipment to run to failure. Deciding what components are critical to the plant is the first step. The industry uses guidance from INPO Advanced Process, AP913, to classify components as Critical, Non Critical or Run to Failure based on the consequence of the failure. Once this is complete, then the right maintenance program needs to be specified. This is done through utilization of experience from the industry based on the type of component. Maintenance strategies and templates have been produced for most power plant components. Each station or fleet needs then to apply the criteria, with exceptions as required, to determine the maintenance requirements and frequency for their components. This includes predictive and preventative maintenance. The more critical the component is the more rigorous the maintenance requirements. Once the maintenance program is defined it can be implemented. This requires that the Preventative Maintenance (PM's) are updated to ensure the correct tasks are in place and the frequency is correct. Work Management will group the PM's so they can scheduled efficiently and to minimize equipment down time. The last element is to ensure that the required parts are specified and are stocked or readily available for the maintenance when it is scheduled. This is an ongoing effort since components become obsolete or suppliers go out of business or change hands. (author)

Effective computing algorithm for maintenance optimization of highly reliable systems

Czech Academy of Sciences Publication Activity Database

Briš, R.; Byczanski, Petr

2013-01-01

Roč. 109, č. 1 (2013), s. 77-85 ISSN 0951-8320 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0070 Institutional support: RVO:68145535 Keywords : exact computing * maintenance * optimization * unavailability Subject RIV: BA - General Mathematics Impact factor: 2.048, year: 2013 http://www.sciencedirect.com/science/article/pii/S0951832012001639

Reliability Considerations for the Operation of Large Accelerator User Facilities

CERN Document Server

Willeke, F.J.

2016-01-01

The lecture provides an overview of considerations relevant for achieving highly reliable operation of accelerator based user facilities. The article starts with an overview of statistical reliability formalism which is followed by high reliability design considerations with examples. The article closes with operational aspects of high reliability such as preventive maintenance and spares inventory.

Pacific Northwest Laboratory Maintenance Implementation plan

International Nuclear Information System (INIS)

Bright, J.D.

1992-06-01

This Maintenance Implementation plan has been developed for Pacific Northwest Laboratory's (PNL) Nuclear Facilities: 306W, 324, 325, 327 and 329NMF. It is based on a graded approach, self-assessment of the existing maintenance program(s) per the requirements specified by US Department of Energy (DOE) Order 4330.4A, Chapter II, Change number-sign 3. The results of this assessment were evaluated to determine needed improvements in PNL Craft Services' current maintenance program. The objective of this implementation plan is to provide baseline information for compliance to the DOE 4330.4A, and for needed improvements. The prime consideration in applying a graded approach to the Order has been to maintain safe and reliable operations, environmental compliance, safeguards and security, programmatic mission, facility preservation, and/or other facility-specific requirements. Using the results of the self-assessment, PNL has selected nine of the 18 elements of the Maintenance Program defined by DOE Order 4330.4A for improvement. The elements selected for improvement are Training and Qualification of Maintenance Personnel; Maintenance Procedures; Planning, Scheduling, and Coordination of Maintenance; Control of Maintenance Activities; Post-Maintenance Testing; Facility Condition Inspection; Management Involvement; Maintenance History; and Additional Maintenance Requirements. Based upon graded approach and current funding, those elements considered most important have been selected as goals for earliest compliance. Commitment dates for these elements have been established for compliance. The remaining elements of noncompliance will be targeted for implementation during later budget periods

Predictive Maintenance (PdM) Centralization for Significant Energy Savings

Energy Technology Data Exchange (ETDEWEB)

Smith, Dale

2010-09-15

Cost effective predictive maintenance (PdM) technologies and basic energy calculations can mine energy savings form processes or maintenance activities. Centralizing and packaging this information correctly empowers facility maintenance and reliability professionals to build financial justification and support for strategies and personnel to weather global economic downturns and competition. Attendees will learn how to: Systematically build a 'pilot project' for applying PdM and tracking systems; Break down a typical electrical bill to calculate energy savings; Use return on investment (ROI) calculations to identify the best and highest value options, strategies and tips for substantiating your energy reduction maintenance strategies.

Adaptation and Implementation of Predictive Maintenance Technique with Nondestructive Testing for Power Plants

International Nuclear Information System (INIS)

Jung, Gye Jo; Jung, Nam Gun

2010-01-01

Many forces are pressuring utilities to reduce operating and maintenance costs without cutting back on reliability or availability. Many utility managers are re-evaluating maintenance strategies to meet these demands. To utilities how to reduce maintenance costs and extent the effective operating life of equipment, predictive maintenance technique can be adapted. Predictive maintenance had three types program which are in-house program, engineering company program and mixed program. We can approach successful predictive maintenance program with 'smart trust' concept

Maintenance-based prognostics of nuclear plant equipment for long-term operation

Energy Technology Data Exchange (ETDEWEB)

Welz, Zachary; Coble, Jamie; Upadhyaya, Belle; Hines, Wes [University of Tennessee, Knoxville (United States)

2017-08-15

While industry understands the importance of keeping equipment operational and well maintained, the importance of tracking maintenance information in reliability models is often overlooked. Prognostic models can be used to predict the failure times of critical equipment, but more often than not, these models assume that all maintenance actions are the same or do not consider maintenance at all. This study investigates the influence of integrating maintenance information on prognostic model prediction accuracy. By incorporating maintenance information to develop maintenance-dependent prognostic models, prediction accuracy was improved by more than 40% compared with traditional maintenance-independent models. This study acts as a proof of concept, showing the importance of utilizing maintenance information in modern prognostics for industrial equipment.

Increasing reliability of nuclear energy equipment and at nuclear power plants

International Nuclear Information System (INIS)

Ochrana, L.

1997-01-01

The Institute of Nuclear Energy at the Technical University in Brno cooperates with nuclear power plants in increasing their reliability. The teaching programme is briefly described. The scientific research programme of the Department of Heat and Nuclear Power Energy Equipment in the field of reliability is based on a complex systematic concept securing a high level of reliability. In 1996 the Department prepared a study dealing with the evaluation of the maintenance system in a nuclear power plant. The proposed techniques make it possible to evaluate the reliability and maintenance characteristics of any individual component in a nuclear power plant, and to monitor, record and evaluate data at any given time intervals. (M.D.)

Integrated Reliability Estimation of a Nuclear Maintenance Robot including a Software

Energy Technology Data Exchange (ETDEWEB)

Eom, Heung Seop; Kim, Jae Hee; Jeong, Kyung Min [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2011-10-15

Conventional reliability estimation techniques such as Fault Tree Analysis (FTA), Reliability Block Diagram (RBD), Markov Model, and Event Tree Analysis (ETA) have been used widely and approved in some industries. Then there are some limitations when we use them for a complicate robot systems including software such as intelligent reactor inspection robots. Therefore an expert's judgment plays an important role in estimating the reliability of a complicate system in practice, because experts can deal with diverse evidence related to the reliability and then perform an inference based on them. The proposed method in this paper combines qualitative and quantitative evidences and performs an inference like experts. Furthermore, it does the work in a formal and in a quantitative way unlike human experts, by the benefits of Bayesian Nets (BNs)

Predictive maintenance primer

International Nuclear Information System (INIS)

Flude, J.W.; Nicholas, J.R.

1991-04-01

This Predictive Maintenance Primer provides utility plant personnel with a single-source reference to predictive maintenance analysis methods and technologies used successfully by utilities and other industries. It is intended to be a ready reference to personnel considering starting, expanding or improving a predictive maintenance program. This Primer includes a discussion of various analysis methods and how they overlap and interrelate. Additionally, eighteen predictive maintenance technologies are discussed in sufficient detail for the user to evaluate the potential of each technology for specific applications. This document is designed to allow inclusion of additional technologies in the future. To gather the information necessary to create this initial Primer the Nuclear Maintenance Applications Center (NMAC) collected experience data from eighteen utilities plus other industry and government sources. NMAC also contacted equipment manufacturers for information pertaining to equipment utilization, maintenance, and technical specifications. The Primer includes a discussion of six methods used by analysts to study predictive maintenance data. These are: trend analysis; pattern recognition; correlation; test against limits or ranges; relative comparison data; and statistical process analysis. Following the analysis methods discussions are detailed descriptions for eighteen technologies analysts have found useful for predictive maintenance programs at power plants and other industrial facilities. Each technology subchapter has a description of the operating principles involved in the technology, a listing of plant equipment where the technology can be applied, and a general description of the monitoring equipment. Additionally, these descriptions include a discussion of results obtained from actual equipment users and preferred analysis techniques to be used on data obtained from the technology. 5 refs., 30 figs

Study on Maintenance Personnel Development Plan For The Exported APR1400 Commissioning

International Nuclear Information System (INIS)

Cho, Sungbae; Kim, Jongdae; Jun, Hokwang; Hwang, Inok; Kang, Jaeyuel

2012-01-01

This paper indicates ways to develop maintenance personnel for the exported APR1400 commissioning. The exported APR1400 has not been experienced ay maintenance yet, and requirements for maintenance personnel have not been clarified yet. Based on sound maintenance experience, KEPCO Plant Service and Engineering Company (KEPCO KPS) has studied on maintenance training and career requirement to establish a development plan of the maintenance personnel for the exported nuclear power plant. By defining manpower and training requirement, and mobilization plan, we expect to secure reliability of the exported APR1400

Implementing a least cost and risk focused maintenance process

International Nuclear Information System (INIS)

Darling, S.S.

1996-01-01

The paper will focus on the vital role maintenance, big ''M'' (spares, PM program, planning and scheduling, turning the wrench), has in preserving return of investment, and safety in operation of high risk high value facilities/platforms. The maintenance process of today and for the future must utilize risk assessment and reliability engineering techniques to prioritize plant resources. The new process must provide for high levels of safety assurance yet allow for improved generation and transmission capacity while maintaining adequate system reliability. This approach ultimately leads to continuous and sustained reduction in operating cost, improved production capacity, and a safety culture based upon a risk determent cost-beneficial decision process

Ultra Reliable Closed Loop Life Support for Long Space Missions

Science.gov (United States)

Jones, Harry W.; Ewert, Michael K.

2010-01-01

Spacecraft human life support systems can achieve ultra reliability by providing sufficient spares to replace all failed components. The additional mass of spares for ultra reliability is approximately equal to the original system mass, provided that the original system reliability is not too low. Acceptable reliability can be achieved for the Space Shuttle and Space Station by preventive maintenance and by replacing failed units. However, on-demand maintenance and repair requires a logistics supply chain in place to provide the needed spares. In contrast, a Mars or other long space mission must take along all the needed spares, since resupply is not possible. Long missions must achieve ultra reliability, a very low failure rate per hour, since they will take years rather than weeks and cannot be cut short if a failure occurs. Also, distant missions have a much higher mass launch cost per kilogram than near-Earth missions. Achieving ultra reliable spacecraft life support systems with acceptable mass will require a well-planned and extensive development effort. Analysis must determine the reliability requirement and allocate it to subsystems and components. Ultra reliability requires reducing the intrinsic failure causes, providing spares to replace failed components and having "graceful" failure modes. Technologies, components, and materials must be selected and designed for high reliability. Long duration testing is needed to confirm very low failure rates. Systems design should segregate the failure causes in the smallest, most easily replaceable parts. The system must be designed, developed, integrated, and tested with system reliability in mind. Maintenance and reparability of failed units must not add to the probability of failure. The overall system must be tested sufficiently to identify any design errors. A program to develop ultra reliable space life support systems with acceptable mass should start soon since it must be a long term effort.

Safety and reliability. V. 1. Proceedings

International Nuclear Information System (INIS)

Soares, C.G.

1997-01-01

Proceedings of a 1997 conference on industrial safety and reliability are reported. The first volume looks at risk management, probabilistic safety assessment and management styles in various industrial settings, including nuclear power plants. The second volume addresses safety and reliability in the offshore and transport industries, focusing on the role of staff training and appropriate maintenance routines to effectively reduce accidents and outages. (UK)

Maintenance viewpoint of a successful reactor program

International Nuclear Information System (INIS)

Moffitt, W.C.; Grygiel, M.L.

1984-05-01

As the Operating and Support staffs of the FFTF organization have gained experience, the plant reliability and capacity factors have shown a steadily improving trend. The plant capacity factor for Cycle 4 was 99.5%. It is the purpose of this report to describe the evolution of the maintenance organization at the FFTF site from a general support organization to a technically proficient organization playing a major role in planning and performance of plant maintenance evolutions

Developing Ultra Reliable Life Support for the Moon and Mars

Science.gov (United States)

Jones, Harry W.

2009-01-01

Recycling life support systems can achieve ultra reliability by using spares to replace failed components. The added mass for spares is approximately equal to the original system mass, provided the original system reliability is not very low. Acceptable reliability can be achieved for the space shuttle and space station by preventive maintenance and by replacing failed units, However, this maintenance and repair depends on a logistics supply chain that provides the needed spares. The Mars mission must take all the needed spares at launch. The Mars mission also must achieve ultra reliability, a very low failure rate per hour, since it requires years rather than weeks and cannot be cut short if a failure occurs. Also, the Mars mission has a much higher mass launch cost per kilogram than shuttle or station. Achieving ultra reliable space life support with acceptable mass will require a well-planned and extensive development effort. Analysis must define the reliability requirement and allocate it to subsystems and components. Technologies, components, and materials must be designed and selected for high reliability. Extensive testing is needed to ascertain very low failure rates. Systems design should segregate the failure causes in the smallest, most easily replaceable parts. The systems must be designed, produced, integrated, and tested without impairing system reliability. Maintenance and failed unit replacement should not introduce any additional probability of failure. The overall system must be tested sufficiently to identify any design errors. A program to develop ultra reliable space life support systems with acceptable mass must start soon if it is to produce timely results for the moon and Mars.

Long-term reliability evaluation of nuclear containments with tendon force degradation

International Nuclear Information System (INIS)

Kim, Sang-Hyo; Choi, Moon-Seock; Joung, Jung-Yeun; Kim, Kun-Soo

2013-01-01

Highlights: • A probabilistic model on long-term degradation of tendon force is developed. • By using the model, we performed reliability evaluation of nuclear containment. • The analysis is also performed for the case with the strict maintenance programme. • We showed how to satisfy the target safety in the containments facing life extension. - Abstract: The long-term reliability of nuclear containment is important for operating nuclear power plants. In particular, long-term reliability should be clarified when the service life of nuclear containment is being extended. This study focuses not only on determining the reliability of nuclear containment but also presenting the reliability improvement by strengthening the containment itself or by running a strict maintenance programme. The degradation characteristics of tendon force are estimated from the data recorded during in-service inspection of containments. A reliability analysis is conducted for a limit state of through-wall cracking, which is conservative, but most crucial limit state. The results of this analysis indicate that reliability is the lowest at 3/4 height of the containment wall. Therefore, this location is the most vulnerable for the specific limit state considered in this analysis. Furthermore, changes in structural reliability owing to an increase in the number of inspecting tendons are analysed for verifying the effect of the maintenance program's intensity on expected containment reliability. In the last part of this study, an example of obtaining target reliability of nuclear containment by strengthening its structural resistance is presented. A case study is conducted for exemplifying the effect of strengthening work on containment reliability, especially during extended service life

Safety, reliability, risk management and human factors: an integrated engineering approach applied to nuclear facilities

International Nuclear Information System (INIS)

Vasconcelos, Vanderley de; Silva, Eliane Magalhaes Pereira da; Costa, Antonio Carlos Lopes da; Reis, Sergio Carneiro dos

2009-01-01

Nuclear energy has an important engineering legacy to share with the conventional industry. Much of the development of the tools related to safety, reliability, risk management, and human factors are associated with nuclear plant processes, mainly because the public concern about nuclear power generation. Despite the close association between these subjects, there are some important different approaches. The reliability engineering approach uses several techniques to minimize the component failures that cause the failure of the complex systems. These techniques include, for instance, redundancy, diversity, standby sparing, safety factors, and reliability centered maintenance. On the other hand system safety is primarily concerned with hazard management, that is, the identification, evaluation and control of hazards. Rather than just look at failure rates or engineering strengths, system safety would examine the interactions among system components. The events that cause accidents may be complex combinations of component failures, faulty maintenance, design errors, human actions, or actuation of instrumentation and control. Then, system safety deals with a broader spectrum of risk management, including: ergonomics, legal requirements, quality control, public acceptance, political considerations, and many other non-technical influences. Taking care of these subjects individually can compromise the completeness of the analysis and the measures associated with both risk reduction, and safety and reliability increasing. Analyzing together the engineering systems and controls of a nuclear facility, their management systems and operational procedures, and the human factors engineering, many benefits can be realized. This paper proposes an integration of these issues based on the application of systems theory. (author)

Safety, reliability, risk management and human factors: an integrated engineering approach applied to nuclear facilities

Energy Technology Data Exchange (ETDEWEB)

Vasconcelos, Vanderley de; Silva, Eliane Magalhaes Pereira da; Costa, Antonio Carlos Lopes da; Reis, Sergio Carneiro dos [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)], e-mail: vasconv@cdtn.br, e-mail: silvaem@cdtn.br, e-mail: aclc@cdtn.br, e-mail: reissc@cdtn.br

2009-07-01

Nuclear energy has an important engineering legacy to share with the conventional industry. Much of the development of the tools related to safety, reliability, risk management, and human factors are associated with nuclear plant processes, mainly because the public concern about nuclear power generation. Despite the close association between these subjects, there are some important different approaches. The reliability engineering approach uses several techniques to minimize the component failures that cause the failure of the complex systems. These techniques include, for instance, redundancy, diversity, standby sparing, safety factors, and reliability centered maintenance. On the other hand system safety is primarily concerned with hazard management, that is, the identification, evaluation and control of hazards. Rather than just look at failure rates or engineering strengths, system safety would examine the interactions among system components. The events that cause accidents may be complex combinations of component failures, faulty maintenance, design errors, human actions, or actuation of instrumentation and control. Then, system safety deals with a broader spectrum of risk management, including: ergonomics, legal requirements, quality control, public acceptance, political considerations, and many other non-technical influences. Taking care of these subjects individually can compromise the completeness of the analysis and the measures associated with both risk reduction, and safety and reliability increasing. Analyzing together the engineering systems and controls of a nuclear facility, their management systems and operational procedures, and the human factors engineering, many benefits can be realized. This paper proposes an integration of these issues based on the application of systems theory. (author)

Implementation of maintenance rule for structures

International Nuclear Information System (INIS)

Ashar, H.; Bagchi, G.

1999-01-01

The maintenance rule, 10 CFR 50.65, 'Requirements for Monitoring the Effectiveness of Maintenance at Nuclear Power Plants', was published by the Nuclear Regulatory Commission (NRC) in the Federal Register (56 FR 31324) on July 10, 1991. The rule became effective on July 10, 1996, giving nuclear power plant licensees 5 years to implement it. During 1994-1995, NRC staff visited nine nuclear power plant sites to observe licensees' preparations for implementation of the rule. The teams found that most of the licensees had not established goals, or performance criteria for monitoring structures at their sites. The licensees contended that the structures were inherently reliable and required no monitoring under the maintenance rule. On the basis of earlier site visits performed by NRC staff to assess the condition of structures, the NRC staff could not accept this contention, and clarified its position in Revision 1 of Regulatory Guide 1.160, 'Monitoring the Effectiveness of Maintenance at Nuclear Power Plants'. This paper discusses the applicability of the maintenance rule criteria for structures and its usefulness in ensuring that the structures, systems, and components within the scope of the maintenance rule are capable of fulfilling their intended functions. Also discussed are the aspects of maintenance rule efforts that could be useful for license renewal applications. (orig.)

GRAPHICAL MODELS OF THE AIRCRAFT MAINTENANCE PROCESS

Directory of Open Access Journals (Sweden)

Stanislav Vladimirovich Daletskiy

2017-01-01

Full Text Available The aircraft maintenance is realized by a rapid sequence of maintenance organizational and technical states, its re- search and analysis are carried out by statistical methods. The maintenance process concludes aircraft technical states con- nected with the objective patterns of technical qualities changes of the aircraft as a maintenance object and organizational states which determine the subjective organization and planning process of aircraft using. The objective maintenance pro- cess is realized in Maintenance and Repair System which does not include maintenance organization and planning and is a set of related elements: aircraft, Maintenance and Repair measures, executors and documentation that sets rules of their interaction for maintaining of the aircraft reliability and readiness for flight. The aircraft organizational and technical states are considered, their characteristics and heuristic estimates of connection in knots and arcs of graphs and of aircraft organi- zational states during regular maintenance and at technical state failure are given. It is shown that in real conditions of air- craft maintenance, planned aircraft technical state control and maintenance control through it, is only defined by Mainte- nance and Repair conditions at a given Maintenance and Repair type and form structures, and correspondingly by setting principles of Maintenance and Repair work types to the execution, due to maintenance, by aircraft and all its units mainte- nance and reconstruction strategies. The realization of planned Maintenance and Repair process determines the one of the constant maintenance component. The proposed graphical models allow to reveal quantitative correlations between graph knots to improve maintenance processes by statistical research methods, what reduces manning, timetable and expenses for providing safe civil aviation aircraft maintenance.