Fault maintenance trees: reliability centered maintenance via statistical model checking

The current trend in infrastructural asset management is towards risk-based (a.k.a. reliability centered) maintenance, promising better performance at lower cost. By maintaining crucial components more intensively than less important ones, dependability increases while costs decrease.\ud \ud This requires good insight into the effect of maintenance on the dependability and associated costs. To gain these insights, we propose a novel framework that integrates fault tree analysis with maintenance. We support a wide range of maintenance procedures and dependability measures, including the system reliability, availability, mean time to failure, as well as the maintenance and failure costs over time, split into different cost components.\ud \ud Technically, our framework is realized via statistical model checking, a state-of-the-art tool for flexible modelling and simulation. Our compositional approach is flexible and extendible. We deploy our framework to two cases from industrial practice: insulated joints, and train compressors

Maintenance Decision Method Based on Risk Level

Maintenance decision method of the mechanical equipment still has some deficiencies and shortcomings, including unreasonable maintenance methods, surplus or insufficient repair, and unscientific inspection and repair intervals, especially for equipment with different risks. As a consequence, more frequent failures and higher maintenance costs of the mechanical equipment occur along with some major safety accidents and economic losses in the process of production. To overcome these problems, a framework for maintenance decision method based on risk level is presented for mechanical equipment in the petrochemical industry. First, 10 evaluation indexes and a set of scoring criteria quantifying the subjective evaluation are defined to evaluate the risk level of each mechanical equipment. Based on the analytic hierarchy process (AHP), the weight of the evaluation indexes and the evaluation model of the risk levels were established. Then, the subjective effects in the scoring process were removed using the Monte Carlo simulation (MCS) approach. Next, maintenance decision-making trees of the mechanical equipment were formulated by referencing the logic decision tree of reliability-centered maintenance. Finally, the feasibility of the framework was effectively verified by testing a well-control system in the oil field, for which the risk level and maintenance methods were obtained

Optimal railway infrastructure maintenance and repair policies to manage risk under uncertainty with adaptive control

The aim of this paper is to apply two adaptive control formulations under uncertainty, say open-loop and closed-loop, to the process of developing maintenance and repair policies for railway infrastructures. To establish the optimal maintenance and repair policies for railway lines, we use a previous design of risk model based on two factors: the criticality and the deterioration ratios of the facilities. Thus, our theory benefits from the Reliability Centered Management methodology application, but it also explicitly models uncertainty in characterizing a facility deterioration rate to decide the optimal policy to maintain the railway infrastructures. This may be the major contribution of this work. To verify the models presented, a computation study has been developed and tested for a real scenario: the railway line Villalba-Cercedilla in Madrid (Spain). Our results demonstrate again that applying any adaptive formulation, the cost of the railway lines maintenance shown is decreased. Moreover applying a Closed Loop Formulation the cost associated to the risk takes smaller values (40% less cost for the same risk than the deterministic approach), but with an Open Loop formulation the generated risk in the railway line is also smaller

OPTIMAL RAILWAY INFRASTRUCTURE MAINTENANCE AND REPAIR POLICIES TO MANAGE RISK UNDER UNCERTAINTY WITH ADAPTIVE CONTROL

The aim of this paper is to apply two adaptive control formulations under uncertainty, say open-loop and closed-loop, to the process of developing maintenance and repair policies for railway infrastructures. To establish the optimal maintenance and repair policies for railway lines, we use a previous design of risk model based on two factors: the criticality and the deterioration ratios of the facilities. Thus, our theory benefits from the Reliability Centered Management methodology application, but it also explicitly models uncertainty in characterizing a facility deterioration rate to decide the optimal policy to maintain the railway infrastructures. This may be the major contribution of this work. To verify the models presented, a computation study has been developed and tested for a real scenario: the railway line Villalba-Cercedilla in Madrid (Spain). Our results demonstrate again that applying any adaptive formulation, the cost of the railway lines maintenance shown is decreased. Moreover applying a Closed Loop Formulation the cost associated to the risk takes smaller values (40% less cost for the same risk than the deterministic approach), but with an Open Loop formulation the generated risk in the railway line is also smaller.

A framework for effective management of condition based maintenance programs in the context of industrial development of E-Maintenance strategies

CBM (Condition Based Maintenance) solutions are increasingly present in industrial systems due to two main circumstances: rapid evolution, without precedents, in the capture and analysis of data and significant cost reduction of supporting technologies. CBM programs in industrial systems can become extremely complex, especially when considering the effective introduction of new capabilities provided by PHM (Prognostics and Health Management) and E-maintenance disciplines. In this scenario, any CBM solution involves the management of numerous technical aspects, that the maintenance manager needs to understand, in order to be implemented properly and effectively, according to the company’s strategy. This paper provides a comprehensive representation of the key components of a generic CBM solution, this is presented using a framework or supporting structure for an effective management of the CBM programs. The concept “symptom of failure”, its corresponding analysis techniques (introduced by ISO 13379-1 and linked with RCM/FMEA analysis), and other international standard for CBM open-software application development (for instance, ISO 13374 and OSA-CBM), are used in the paper for the development of the framework. An original template has been developed, adopting the formal structure of RCM analysis templates, to integrate the information of the PHM techniques used to capture the failure mode behaviour and to manage maintenance. Finally, a case study describes the framework using the referred template.Gobierno de Andalucía P11-TEP-7303 M

Critical Review of Reliability Centred Maintenance (RCM) for Asset Management in Electric Power Distribution System

The purpose of maintenance is to extend equipment lifetime or at least the mean time to the next failure. Maintenance too incurs expenditures that result in very costly consequences when not performed or performed too little, and it may not even be economical to perform it too frequently. Therefore the two costs must be balanced. In the past, this balance had been estimated by extrapolating the experience obtained from existing systems and using the rule - of – thumb methods. Nowadays, the tempo of advanced and softiscated research in that direction has rendered such rule – of – thumb methods obsolete. The literature works describing the reliability centred maintenance methods for managing distribution assets have grown until the papers can now be numbered in thousands. This paper presents critical review of the various existing methods that have been developed by different reseachers and proposes a probabilistic model that will provide a quantitative connection between reliability and maintenance, a link missing in all the heuristic approaches

Cyber physical systems implementation for asset management improvement: A framework for the transition

Libro en Open AccessThe transformation of the industry due to recent technologies introduction is an evolving process whose engines are competitiveness and sustainability, understood in its broadest sense (environmental, economic and social). This process is facing, due to the current state of scientific and technological development, a new challenge yet even more important: the transition from discrete technological solutions that respond to isolated problems, to a global conception where the assets, plant, processes and engineering systems are conceived, designed and operated as an integrated complex unit. This vision is evolving besides a set of concepts that are, in some way, to guide this development: Smart Factories, Cyber-Physical Systems, Factory of the Future or Industry 4.0, are examples. The full integration of the operation and maintenance (O&M) processes in the production systems is a key topic within this new paradigm. Not only that, this evolution necessarily results in the emergence of new processes and needs of O&M, i.e. also, the O&M will undergo a profound transformation. The transition from actual isolated production assets to such Industry 4.0 with CPS is far from easy. This document presents a proposal to develop such transition adapting one iteration of the Model of Maintenance Management (MMM) integrated into ISO 55000 to the complexity of incorporating “System of Systems” CPSs maintenance. It involves several stages: identification, prioritization, risk management, planning, scheduling, execution, control, and improvement supported by system engineering techniques and agile/concurrent project managemen

Integrated reliability centred maintenance approach in public sector facilities management.

Reliability Centred Maintenance (RCM) is focused on ensuring an asset continues to provide its designed function in its present operating context. Through a number of stages, RCM allows for thorough and constant monitoring of assets to maintain their level of performance, expand life cycle and improve efficiency. A conceptual holistic framework was developed embedding RCM approach and assessing the impact of maintenance strategies in four dimensions: business, functional, legal and context requirements to ensure optimum level of maintenance. A prototype spread-sheet model was developed encapsulating the concept and the model was evaluated using a case study. The preliminary evaluation has shown the potential of the model to realise benefits and improve reliability of the services of the assets to the clients/users. Further research and development is essential in order to calibrate model parameters to specific company requirements as well as to develop a database of assets with failure patterns and monitoring methods