Orientadores: João Maurício Rosário, José António Tenreiro Machado / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-19T05:49:27Z (GMT). No. of bitstreams: 1 GutierrezCarvajal_RicardoEnrique_D.pdf: 5678038 bytes, checksum: 2d6613e04b5a55fb2cf01fb83210ee32 (MD5) Previous issue date: 2011 / Resumo: A competitividade no mercado global exige cada vez mais a fabricação de produtos de alta qualidade em curto tempo de fabricação, evitando tempos de parada para manutenção e reparo de máquinas e equipamentos, exigindo assim um eficiente controle de qualidade do processo e dos produtos para evitar a ocorrência de falhas de fabricação e utilização. A integração de novas tecnologias em produtos industriais (ex. tecnologias mecatrônicas) exige a utilização de técnicas avançadas para o diagnóstico de falhas, a partir de análise dos sinais obtidos a partir do sensoriamento dos equipamentos, minimizando assim os custos de utilização de mão de obra especializada para controle de qualidade do produto. Neste trabalho é apresentado inicialmente, um estudo sobre o estado da arte em técnicas de manutenção industrial, com ênfase nas estratégias utilizadas para manutenção corretiva, periódica e baseada no comportamento com ênfase no estudo das técnicas de processamento do sinal e identificação de sistemas, frequentemente utilizadas no diagnóstico de sistemas mecatrônicos, que exigem uma grande quantidade de informações, e forte dependência da análise criteriosa de um técnico especializado. Assim, neste trabalho são utilizados sistemas de ordem fracionária, que permite a aproximação do comportamento real do sistema por meio de modelos com menos coeficientes que o sistema real, simplificando a análise do sistema em estudo. Um estudo experimental de caso para validação do trabalho é realizado a partir de uma bancada experimental de um sistema de transmissão por engrenagens que permitiu introduzir falhas particulares no sistema e sua identificação / Abstract: The global market competitiveness requires to make high quality products in a short time of manufacturing, avoiding stop-times due to maintenance and repairing of machines and devices, therefore, demanding an efficient quality control of the manufacturing process, in order to shun failures in fabrication and utilization. The integration of new technologies into industrial products (e.g. mechatronics technologies) requires the use of advanced techniques to a precise failure diagnosis. They are typically based on signal analyses, which are obtained from the machines' instrumentation, and consequently, reduce the manpower costs associated to quality control of particular products. In this work it is introduced a literature review of industrial maintenance techniques, focusing in the strategies used into corrective, periodic and condition based maintenance, specially using signal processing and system identification. Those paradigms are frequently applied into the mechatronics systems diagnosis, but requires a huge amount of information and it is strongly dependent on the specialist criterion. In this sense, we introduced a fractional order system approach, which results in a better approximation of the actual system through an few parameters architecture, hence simplifying the analysis of the actual system. A real experimental setup was used to validate the strategies studied in this work. It consist in a gear transmission that lets to introduce particular failures for a posterior identification / Doutorado / Mecanica dos Sólidos e Projeto Mecanico / Doutor em Engenharia Mecânica

Submitted by Secretaria Pós de Produção (tpp@vm.uff.br) on 2017-07-27T19:06:31Z No. of bitstreams: 1 D2016 - Ronaldo Camara Cavalcante.pdf: 3467058 bytes, checksum: 7ffa144584e3a6c9c1e5ac461e387f19 (MD5) / Made available in DSpace on 2017-07-27T19:06:31Z (GMT). No. of bitstreams: 1 D2016 - Ronaldo Camara Cavalcante.pdf: 3467058 bytes, checksum: 7ffa144584e3a6c9c1e5ac461e387f19 (MD5) / O objetivo central da tese é o desenvolvimento de um modelo de Gerenciamento capaz de dotar os projetos ditos complexos de uma maior capacidade de atendimento as necessidades de manutenção. Para tal foi desenvolvido um amplo estudo bibliográfico para identificar oportunidades de melhoria na gestão dos empreendimentos complexos de forma a identificar lacunas no gerenciamento da manutenção neste tipo de projetos. A partir deste levantamento foi identificada a necessidade da promoção de uma maior aderência dos atributos de construtibilidade, operabilidade e de projeto de engenharia aos atributos de manutenabilidade durante todo o ciclo de vida do projeto obtendo-se assim um modelo antecipativo de gestão capaz de aumentar a previsibilidade das atividades de manutenção incrementando assim a eficiência produtiva dos projetos em sua fase operacional. Para a proposição e posterior validação do modelo foram realizadas pesquisas de cunho tanto qualitativo quanto quantitativo. Na pesquisa qualitativa foram conduzidas entrevistas com especialistas no setor para embasar as lacunas de gerenciamento da manutenção e verificar sua importância relativa junto a grandes empresas. Na fase de pesquisa quantitativa foi aplicado um questionário contendo os atributos de projeto de engenharia, manutenabilidade, construtibilidade e operabilidade de forma a verificar a aderência destes atributos entre si para assim suportar as hipóteses de pesquisa que envolvem o modelo de gestão. As pesquisas foram conduzidas com forte enfoque e direcionamento para especialistas em gestão de projetos de grande porte que ocupassem posições gerenciais, para assim aumentar a confiabilidade das proposições do modelo. O resultado final da pesquisa foi um modelo integrado de manutenção com sugestões de pacotes de entrega para as fases do ciclo de vida do projeto baseada na metodologia FEL (Front End Loading). / The main purpose of this thesis is the development of a model of management capable of providing the so-called complex projects with greater capacity to meet maintenance needs. To do so a large bibliographic study was held to identify opportunities for improvement in the management of complex projects in order to identify gaps in maintenance management in this type of projects. From this research it was identified the need to promote a greater adherence of the attributes of constructability, operability and engineering design with the attributes of maintainability throughout the lifecycle of the project thus obtaining a anticipated management model able to increase the predictability of maintenance activities thereby increasing productivity and the efficiency of the projects in its operational phase. To the proposition and subsequent model validation were conducted qualitative and quantitative research studies. In qualitative research interviews with industry experts were conducted to support gaps in maintenance management and verify their relative importance with major companies. On the quantitative research phase, a questionnaire containing the attributes of engineering design, maintainability, constructability and operability was held in order to verify the adherence of these attributes together to verify the research hypotheses involving the management model. The surveys were conducted with a strong focus and direction to management experts of large projects that occupy managerial positions, thus increasing the reliability of the propositions of the model. The final result of this research was an integrated maintenance model with suggestions for delivery package through the phases of the project life cycle using a methodology based on the FEL (Front End Loading) model.

The research made in the current master thesis uses theoretical framework from the area of project management, voluntary labor turnover and performance appraisal. Prior research based on existing literary sources allows assuming that the following factors, such as job alternatives, knowledge intensity and nature of work have specific relevance for the emergence of voluntary labor turnover in project-based organizations. Employees of the case study company-AGR Field Operations´ Maintenance Engineering department were interviewed and surveyed in order to determine the relevance of those factors on the example of a concrete project-based organization. The obtained results indicate that the nature of work is more significantly related to the emergence of the voluntary labor turnover in the given case study department. Whereas availability of more job alternatives due to being close to the client or knowledge intensity factor of becoming more generalist do not have the same influence. During the course of the research it was discovered that the department uses outcome-based type of performance appraisal which is proved to be unsuitable in the given organizational settings. To that matter there were provided further suggestions in the field of performance appraisal. The current research will attempt to identify specific factors contributing to the emergence of the voluntary labor turnover specifically for project-based organizations. As well as it will attempt to give suggestions for improvement of the concrete case study department´s performance appraisal tools and thus supplement turnover reduction actions already put in place by the department management.

Production Line Systems (PLS) are ubiquitous in today’s manufacturing industry. The need for enhanced efficiencies and higher throughput in such systems has increased their complexity and size that has made performance analysis challenging for practitioners. This thesis introduces a novel approach based on Product Service System (PSS) design and analysis which simplifies Production Line System study and identifies opportunities for performance improvement that can be quantified based on the hardware and maintenance system performance. The approach involves modelling and simulation techniques based on reliability engineering principles and systems thinking. In order to apply the principles of PSS approach to PLS, it is essential to draw a comparison between PLS and PSS, so as to take account of the differences while applying the new approach; a literature review has been carried out on PSS Design and Analysis, that identified the state of the art modelling and simulation techniques in PSS. Additionally, a separate literature review on maintenance system and production line was carried out. This enabled the PSS methodology to be applied to PLS by incorporating the differences. A systems thinking approach has been employed to create the static simulation model of the integrated production line system by means of schematic representations. Key improvement areas, identified from the static simulation model have been modelled dynamically to incorporate the stochastic behaviour of the system. All the dynamic models are developed using a Discrete Event Simulation platform. These models were supported by Monte Carlo Simulation, queuing principles, probabilistical and statistical methods pertinent to reliability engineering. The novel integrated simulation model consists of a production line model and a maintenance system model. The production line model simulates two types of failures in addition to the outages in the system: breakdowns and short stops. The maintenance system model simulates the maintenance actions in the production line by considering the resources availability, repair time, and resources travelling time amongst others. In addition, the maintenance model is capable of optimizing the preventive maintenance interval for maintainable failures for cost, availability and criticality while taking into account the maintenance effectiveness value from the failure data. The simulation model is validated using an industrial case study which consists of a large production line for beer. Sensitivity studies on the simulation model enabled the case study company to focus on strategies for throughput improvement by improving the reliability and maintainability, optimal resources allocation and maintenance interval optimization in targeted areas in the large and complex system. The model developed is generic and can easily be applied to analyse other industrial production line systems. It can also be used as a design tool for new production lines.

JYSK is one of North Europe's largest furniture suppliers with over 2 800 stores. The central warehouse located in Nässjö delivers to all of Sweden and although the company is well established on the market, there are shortcomings in the maintenance work. This cause for unnecessary breaks in the logistics chain which contributes to a lower availability. The purpose of this study was to bring forth suitable action proposals that could help JYSK in their effort in establishing a functioning maintenance.  To answer the study's purpose three questions had been presented: 1.     What type of stops occurs and what metrics can be used to calculate the availability? 2.     How is the suppliers’ maintenance-plan designed for each equipment? 3.     Which maintenance work should be prioritized by JYSK, based on the existing and suppliers' maintenance plans?  The study´s major demarcation was towards fully automated equipment only as well as no metrics was calculated and presented.  A case study consisting of a literature study was accomplished with the purpose to gather data to be able to answer the questions. Qualitative methods that was accomplished was an interview, observations, and document collection.  The result presented in this study was a well-developed maintenance plan, checklists based on the recommendation of the supplier and suggestions on follow ups that focuses on visualisation and metrics.    The study's conclusion was that JYSK had all the necessary tools and instructions on how to develop and implement a working maintenance plan provided. The company only had to implement the given recommendations in their everyday routine. It was necessary for JYSK to identify the causes behind the stops to be able to eliminate them.

Reliable and efficient utilization and operation of any engineering asset require carefully designed maintenance planning and maintenance related data in the form of failure times, repair times, Mean Time between Failure (MTBF) and conditioning data etc. play a pivotal role in maintenance decision support. With the advancement in data analytics sciences and industrial artificial intelligence, maintenance related data is being used for maintenance prognostics modeling to predict future maintenance requirements that form the basis of maintenance design and planning in any maintenance-conscious industry like railways. The lack of such available data creates a no. of different types of problems in data driven prognostics modelling. There have been a few methods, the researchers have employed to counter the problems due to lack of available data. The proposed methodology involves data augmentation technique using Markov Chain Monte Carlo (MCMC) Simulation to enhance maintenance data to be used in maintenance prognostics modeling that can serve as basis for better maintenance decision support and planning.

Orientador: José Antonio Siqueira Dias / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-25T04:25:15Z (GMT). No. of bitstreams: 1 Soares_PaulodaSilva_D.pdf: 5062177 bytes, checksum: b08acd7cd74b46ed7ade778b2cbed7cf (MD5) Previous issue date: 2014 / Resumo: Neste trabalho é apresentado o desenvolvimento de um sistema de baixo custo para monitoração e acompanhamento de equipamentos industriais com vistas à manutenção preditiva. O sistema desenvolvido monitora a vibração do elemento em estudo, e faz o registro da mesma comparando-se a um padrão de vibração considerado nominal, ou seja, uma condição de operação satisfatória da máquina. Quando uma variação na vibração do dispositivo monitorado é identificada, há de se observar seu comportamento, não só de amplitude mas também no espectro de frequência, pois geralmente a incidência de falhas ou anomalias apresentam vibrações em frequências diferentes da nominal de trabalho de um dispositivo. A Transformada de Fourier do sinal e os registros de leituras frequentes nos permitem um acompanhamento contínuo do equipamento monitorado. Adicionalmente ao acompanhamento da vibração mecânica, faz-se o monitoramento da corrente elétrica do motor de acionamento do elemento para observância de eventual sobrecarga, desequilíbrio das fases e análise do espectro de frequência do sinal elétrico de corrente, que nos permite avaliar as alterações na alimentação do mesmo, indicando alguma anomalia de natureza elétrica ao motor em estudo. Por fim ainda monitora-se a temperatura dos elementos em estudo, pois a vida útil destes depende das temperaturas a que são submetidos em regime de operação que têm impacto direto em isolamentos de bobinas e lubrificantes das partes mecânicas. Este sistema permite uma avaliação de uma máquina, sem intervenção humana para as medições de vibração e elétricas, aliado ao histórico levantado, torna-se uma ferramenta poderosa para a implementação de um programa de manutenção preditiva / Abstract: This work aims to develop a low-cost system for monitoring and tracking of industrial equipment with a view to predictive maintenance. It presents a system that monitors vibration of the recording studied element comparing the same to a vibration pattern considered nominal. When it detects a change in the vibration of the device is to observe their behavior, not only amplitude but in the frequency spectrum, usually because the incidence of faults or anomalies exhibit vibrations at different frequencies of nominal working of a device. The Fourier transform of the signal and records of frequent readings allow to close monitoring of the element under study. In addition to monitoring the mechanical vibration, it is monitoring the electrical current of the motor drive element for compliance with any overload, phase imbalance and even the analysis of spectro signal frequency electric current, which allows us to evaluate changes feeding the same, indicating an abnormality of the electric motor in nature study. Finally even monitor the temperature of the elements under study, because the life of these depends on the temperatures to which they are subjected in operation regime that have direct impact on coil insulation and lubricants of the mechanical parts. This system permits an automatic evaluation of the condition of a machine, without human intervention for measurement of vibration and electrical therein, together with the historical raised, becomes a powerful tool for industry implementation of a predictive maintenance program / Doutorado / Eletrônica, Microeletrônica e Optoeletrônica / Doutor em Engenharia Elétrica

Em sistemas modernos de manutenção inteligente a qualidade de uma máquina ou equipamento depende do suporte que é fornecido junto com esse produto, com a confiabilidade e segurança na utilização do mesmo. Estas exigências, por vezes, não são cumpridas e podem estar indisponíveis em algumas máquinas. Este trabalho descreve uma abordagem utilizando sinais de vibração coletados em tempo real com falhas como estudo preliminar para uma abordagem mais profunda como estudo dametodologia de testes de vida acelerado para auxiliar durante a fase de vida operacional permitindo ao fabricante a determinação dos ciclos de vida do produto. A abordagem proposta construída em cima de experiências anteriores em desenvolvimento no projeto Integração de Sistemas Inteligentes de Manutenção e Cadeia de Fornecimento de Peças Sobressalentes. O objetivo deste trabalho é apresentar resultados preliminares analisando a variabilidade das assinaturas de falhas das engrenagens danificadas de maneira a permitir a identificação dos ciclos de vida do produto para partes específicas de um atuador elétrico. / In modern systems of intelligent maintenance the quality of a machine or equipment depends on the support that comes with this product, with the reliability and safety in the use of it. These requirements are sometimes not met and may be unavailable on some machines. This paper describes an approach using vibration signals collected in real-time with faults as a preliminary study for a deeper approach with the study of the methodology of accelerated life tests to assist during the operational life stage allowing the manufacturer the determination of the life cycles of product. The proposed approach built on previous experiences under development in the project Integration of Intelligent Systems of Maintenance and Chain of Supply of Spares. The objective of this work is to present preliminary results analyzing the variability of failure signatures of the damaged gears in order to allow the identification of product life cycles for specific parts of an electric actuator.

Em sistemas modernos de manutenção inteligente a qualidade de uma máquina ou equipamento depende do suporte que é fornecido junto com esse produto, com a confiabilidade e segurança na utilização do mesmo. Estas exigências, por vezes, não são cumpridas e podem estar indisponíveis em algumas máquinas. Este trabalho descreve uma abordagem utilizando sinais de vibração coletados em tempo real com falhas como estudo preliminar para uma abordagem mais profunda como estudo dametodologia de testes de vida acelerado para auxiliar durante a fase de vida operacional permitindo ao fabricante a determinação dos ciclos de vida do produto. A abordagem proposta construída em cima de experiências anteriores em desenvolvimento no projeto Integração de Sistemas Inteligentes de Manutenção e Cadeia de Fornecimento de Peças Sobressalentes. O objetivo deste trabalho é apresentar resultados preliminares analisando a variabilidade das assinaturas de falhas das engrenagens danificadas de maneira a permitir a identificação dos ciclos de vida do produto para partes específicas de um atuador elétrico. / In modern systems of intelligent maintenance the quality of a machine or equipment depends on the support that comes with this product, with the reliability and safety in the use of it. These requirements are sometimes not met and may be unavailable on some machines. This paper describes an approach using vibration signals collected in real-time with faults as a preliminary study for a deeper approach with the study of the methodology of accelerated life tests to assist during the operational life stage allowing the manufacturer the determination of the life cycles of product. The proposed approach built on previous experiences under development in the project Integration of Intelligent Systems of Maintenance and Chain of Supply of Spares. The objective of this work is to present preliminary results analyzing the variability of failure signatures of the damaged gears in order to allow the identification of product life cycles for specific parts of an electric actuator.

Made available in DSpace on 2016-06-02T20:09:16Z (GMT). No. of bitstreams: 1 4472.pdf: 3417469 bytes, checksum: a57b6e0d1b492e13b56e0de18bcf7619 (MD5) Previous issue date: 2012-08-22 / To avoid the maintenance, in other words, to look for forms of avoiding the flaws and not of correcting them. This concept summarizes the current scenery of the function maintenance. It is known that the maintenance activities generate great earnings to the productive processes. Being like this, the maintenance contributes in an essential way to the conservation, valorization, increase of the productivity, in addition the lack of the same can generate great economical problems, social and environmental. Regarding the property maintenance, it is verified that this is still on this side of the ideal. The objective of this work is now it of evaluating the processes used in public entities for accomplishment of the activities of property maintenance. For this end, studies of the bibliography were accomplished related to the maintenance in addition case studies in three entities of the indirect public administration, located in the city of São Carlos/SP. The results obtained through the observations, ally to the bibliographical references contributed to map the processes now developed by the studied entities, in addition to identify the "bottlenecks", in other words, limitations of the efficiency capacity inside of the necessary processes for accomplishment of the services of property maintenance. Finally, some points for improvement of the installment of the services of property maintenance were proposed. / Evitar a manutenção, ou seja, buscar formas de se evitar as falhas e não de corrigi-las. Este conceito resume o cenário atual da função manutenção. Sabe-se que as atividades de manutenção geram grandes ganhos aos processos produtivos. Sendo assim, a manutenção contribui de forma essencial para a conservação, valorização, aumento da produtividade, além do que, a falta da mesma pode gerar grandes problemas econômicos, sociais e ambientais. Com relação à manutenção predial, verifica-se que esta ainda está aquém do ideal. O objetivo deste trabalho é o de avaliar os processos atualmente utilizados em entidades públicas para realização das atividades de manutenção predial. Para este fim, foram realizados estudos da bibliografia relacionados à manutenção, além de estudos de caso em três entidades da administração pública indireta, localizadas na cidade de São Carlos/SP. Os resultados obtidos através das observações, aliado às referências bibliográficas contribuíram para mapear os processos atualmente desenvolvidos pelas entidades estudadas, além do que identificar os gargalos , ou seja, limitadores da capacidade de eficiência dentro dos processos necessários para realização dos serviços de manutenção predial. Por fim, alguns pontos para melhoria da prestação dos serviços de manutenção predial foram propostos.