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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Análise crítica de experiências e discussão de estratégias para implantação de leis de inspeção de elementos de fachadas / Critical analysis on experiences and discussion of strategies for the implementation of façade element inspection laws

Oliveira, Cristiane Sardin Padilla de January 2013 (has links)
O presente trabalho faz uma avaliação do histórico de desenvolvimento e aplicação de leis de inspeções prediais em geral no Brasil, com foco particular nas leis especificas de inspeção de elementos de fachada. O mesmo busca discutir os papéis dessas leis como instrumentos de gestão de riscos na construção civil, destacando os avanços, limitações e tendências do processo de implantação desse tipo de legislação. A lógica e o conhecimento teórico acumulado na área indicam que a adoção de um sistema de inspeção adequado pode contribuir para a detecção precoce de problemas, que podem então ser corrigidos através de ações de manutenção preventiva, com menor custo e risco para os usuários. Essa é uma demanda fundamental em muitas cidades brasileiras, que apresentam um conjunto de edificações em idade avançada e com problemas de conservação. Sinistros repetidos, culminando na tragédia ocorrida no Rio de Janeiro em 2012, fizeram com que a edição de leis de inspeção entrasse na pauta política de várias administrações e do Congresso Nacional. Todavia, a análise de experiências práticas evidencia que existem dificuldades e obstáculos, culturais, técnicos e econômicos, que necessitam ser discutidos e superados para que uma estratégia de gestão de risco através de leis de inspeção possa ser adotada de forma eficaz. O trabalho busca colaborar com essa discussão, revisando criticamente a experiência de Porto Alegre, um dos primeiros municípios a implantar uma lei de inspeção específica de elementos de fachada, a Lei Municipal nº 6.323/88, regulamentada pelo Decreto 9425. Esses regramentos determinaram que os responsáveis pelas edificações apresentassem à Secretaria Municipal de Obras e Viação (SMOV), a cada 03 anos, um laudo de estabilidade estrutural das marquises localizadas sobre logradouros públicos. Essa lei, popularizada como “Lei das Marquises”, foi criada em resposta a 2 sinistros traumáticos envolvendo a queda de seções de marquises no centro da cidade, ocorridos no final dos anos 80, e teve um impacto importante no estado de conservação do estoque de marquises da cidade. Ao mesmo tempo, representou um marco significativo no histórico de implantação de leis de inspeção no Brasil, tendo influenciado vários outros municípios a adotar legislações semelhantes. Após 30 anos, considera-se importante avaliar seus efeitos e analisar as evoluções e dificuldades enfrentadas em sua aplicação, de forma a que seja possível orientar outras experiências. Essa é a motivação fundamental da pesquisa. Para complementar e enriquecer as análises, o trabalho buscou gerar um indicativo da eficiência e qualidade dos Laudos de Marquise que estão sendo entregues. Com esse intuito, a autora, auxiliada por outros pesquisadores do Grupo LEME/UFRGS, efetuou uma inspeção paralela de 135 estruturas, gerando dados usados para comparação com os constantes em laudos arquivados na Secretaria Municipal de Obras e Viação (SMOV). Em paralelo, se buscou uma forma de avaliar qual a percepção da população acerca dos conceitos associados à implantação de leis de inspeção e estratégias de manutenção preventiva, e estimar qual a aceitação dos custos associados a essas estratégias. Para tanto foi realizado um levantamento de dados, através de entrevistas e questionários, junto a usuários de 24 edificações da região metropolitana de Porto Alegre. Esse esforço evidenciou que existe um bom conhecimento dos riscos e uma aceitação da necessidade de inspeções, mas que o custo ainda é uma barreira. Visando aproveitar e consolidar todo o conhecimento adquirido nessas diversas análises, o trabalho finaliza apresentando uma proposta de diretrizes consideradas úteis para orientar a implantação de leis de inspeção de elementos de fachada. / This study evaluated the history of the development and application of building inspection laws in Brazil in general, with special focus on specific laws for the inspection of façade elements. The role of these laws as risk management tools in civil construction is discussed, stressing developments, limitations and trends of their implementation process. Logics and the theoretical knowledge accumulated on this subject suggest that the adoption of a proper system may allow the early detection of problems, which can then be corrected by preventive maintenance actions, and therefore are less costly and pose fewer risks to the users. This is a critical demand in many Brazilian cities that have many old buildings with conservation problems. Repeated accidents, which culminated in the tragedy in Rio de Janeiro in 2012, inserted the issuing of inspection laws in the political agenda of many local administrations and of the National Congress. However, the analysis of practical experiences shows that there are cultural, technical, and economic obstacles that need to be discussed and overcome to allow the adoption of an efficient risk management strategy based on inspection laws. This study aims at contributing for this discussion making a critical review of the experience of Porto Alegre, which was one of the first cities to implement a specific law for the inspection of façade elements (Municipal Act n. 6.323/88, regulated by Order 9425). These regulations established that those responsible for the building have to present to the local department of works (Secretaria Municipal de Obras e Viação – SMOV) a report on the structural stability of the marquees located on public areas every three years. This so-called “Marquee Act” was issued in response to two severe accidents that involved the fall of marquee sections downtown by the end of the 1980s and that had an important impact on the conservation status of the city’s marquee inventory. It was also a landmark in the history of the implementation of inspection laws in Brazil, as it influenced the adoption of similar legislation in other cities. After 30 years, it is important to evaluate its effects and to analyze the advances and obstacles to their application in order to guide other experiences. This is the main motivation of this research study. In order to complement and enrich the analyses, an indication of efficiency and quality of the marquee reports is pursued. Based on a parallel inspection of 135 structures, made by the author, with the aid of other researchers of the group LEME/UFRGS, data was collected to compare with those reported and filed at the local department of works (SMOV). Also, a survey of the public perception relative to the concepts associated with the implementation of inspection laws and preventive maintenance strategies was carried out, checking the acceptance of the costs associated with these strategies. This assessment was made using interviews and questionnaires applied to users of 24 buildings of the metropolitan region of Porto Alegre. The results showed that the population is aware of the risks and accepts the need for inspections, but that cost is still an obstacle. Aiming at using and consolidating the knowledge acquired through these analyses, the study ends proposing some guidelines considered useful for the implementation of façade element inspection laws.
32

Melhoria do pilar "manutenção planejada" da TPM através da utilização do RCM para nortear as estratégias de manutenção

Souza, Fábio Januário de January 2004 (has links)
O atual ambiente competitivo, onde baixo custo, alta qualidade e um grau crescente de customização são exigências para a sobrevivência das empresas, tem influenciado as ações dos profissionais de manutenção com vistas ao aprimoramento das políticas de manutenção. Como resultado, tem-se na área de manutenção industrial, uma grande quantidade de métodos, software, modelos e ferramentas de gestão disponíveis. Dentre eles, dois métodos se destacam: o RCM (Reliability Centered Maintenance ou Manutenção Centrada em Confiabilidade), de origem norte-americana, e a TPM (Total Productive Maintenance ou Manutenção Produtiva Total), de origem japonesa. A TPM promove a integração total entre homem, máquina e empresa, onde a manutenção dos meios de produção passa a constituir uma responsabilidade de todos. A utilização da TPM contempla a implementação de pilares de sustentação, sendo um deles, a manutenção planejada. Entretanto, a TPM não especifica a estratégia a ser adotada pela manutenção planejada. O RCM é uma metodologia lógica de procedimentos que objetiva estabelecer uma manutenção preditiva e preventiva para alcançar, de maneira efetiva e eficiente, os níveis de segurança e confiabilidade requeridas para cada equipamento. Considerando um ambiente com a TPM já implementada, o objetivo deste trabalho é a melhoria do pilar Manutenção Planejada da TPM através da utilização do RCM para nortear as estratégias de manutenção em empresas industriais. A sistemática proposta é ilustrada através de um estudo de caso na indústria de conformação de metais. / Today’s competitive business environment, in which low costs, high quality and an ever increasing degree of customization are essential for companies’ survival has influenced maintenance professionals’ courses of action, aiming at improving maintenance policies. As a result, in the industrial maintenance sector there is a great number of methods, software and management tools available. Among them, two stand out: the RCM (Reliability Centered Maintenance), a North American approach, and the TPM (Total productive Maintenance), a Japanese approach. TPM promotes total integration among manpower, machines and the company itself, and the maintenance of the means of production is everybody’s responsibility. The introduction of TPM demands the implementation of the so called sustaining pillars, and planned maintenance is one of them. However, TPM does not specify the strategy to be followed by planned maintenance. RCM is a set of logical procedures aiming at setting up predictive and preventive maintenance in order to effectively and efficiently achieve the security and reliability standards required for each equipment. Considering an environment where TPM has already been implemented, this paper aims at optimizing Planned Maintenance of the TPM by using RCM to guide maintenance strategies in industries. The system proposed is illustrated through a case study in a metal cold roll forming factory.
33

Estudo e análise de confiabilidade e manutenção em pavimentos asfálticos: uma abordagem delay time modelling

MUCHANGA, Armando 01 February 2016 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-08-05T13:16:00Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Armando Muchanga.pdf certa.pdf: 9213756 bytes, checksum: e7f44528d62ad3cf348371353e3934a6 (MD5) / Made available in DSpace on 2016-08-05T13:16:00Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Armando Muchanga.pdf certa.pdf: 9213756 bytes, checksum: e7f44528d62ad3cf348371353e3934a6 (MD5) Previous issue date: 2016-02-01 / CNPq / O desenvolvimento urbano depende de vários setores, e o mais importante, além de mais caro nos custos de urbanização é o setor de infraestrutura de transporte, responsável pela pavimentação e manutenção das vias. Com o aumento acelerado de veículos que trafegam nas vias, para um departamento de transporte manter uma rede viária urbana sob os níveis de desempenho requeridos ao longo da vida útil do pavimento é necessário que haja um melhor gerenciamento das atividades de manutenção. De todos os tipos de defeitos dos pavimentos, os que mais preocupam os usuários das vias, gestor e os técnicos da manutenção são os buracos. Alinhada a este fato exposto, esta dissertação propõe um modelo Delay Time para determinar o período ótimo de inspeção e manutenção preventiva dos pavimentos asfálticos urbanos, em particular das vias da cidade de Recife, de modo a minimizar os custos de manutenção. Primeiro são exploradas as abordagem de modelo Delay Time, para analisar a que se adequa aos pavimentos asfáltico. E a abordagem proposta é Delay Time do sistema complexo, sujeito a várias falhas, com inspeção perfeita e taxa de chega de defeitos homogênea. Os pavimentos são sujeitos a vários tipos de defeitos, mas este trabalho considerou os buracos por serem os defeitos que mais gastam no custo de manutenção. Também é feita uma revisão dos trabalhos que contribuíram para investigação e aplicação do modelo Delay Time. Ainda neste trabalha é apresentado uma revisão das normas dos pavimentos asfáltico, bem como a politica de manutenção “Operação Tapa-Buraco” praticada atualmente nas vias da cidade de Recife para tapar os buracos. O modelo proposto mostra se viável e não é sensível quando variam os parâmetros de entra, os resultados obtidos são fáceis de aplicar se o setor de manutenção de pavimento da cidade de Recife incluir as hipóteses do modelo na “Operação Tapa-Buraco”. / The urban development depends on several sectors, the most important, beyond most expensive, comes from the transport infrastructure sector - that is responsible for paving and maintenance of roads. Due the rapid increase of vehicles on roads, for the transport department to keep an urban road network under the performance levels required it is necessary to invest in a better management of maintenance activities. Among all types of floors of defects, the primary concern to road users, managers and maintenance technicians are the holes. In sum to this stated fact, this dissertation proposes a Delay Time model to determine the optimal period of inspection and preventive maintenance of urban asphalt pavements, particularly for the roads of the city of Recife, in order to minimize maintenance costs. First it was explored the Delay Time model approach to analyse which applies to the asphalt pavements. The proposed approach is Delay Time of complex system, subject to several failures, with perfect inspection and a homogeneous rate of defects arrival. Besides the floors being subject to various types of defects, this work only considers holes as defects that cause more impact on the maintenance cost. It is also made a review of the works that contributed to research and application of Delay Time Models. Also in this work is presented a review of the standards of asphalt pavements, as well as the maintenance policy "Operação Tapa-Buraco", currently practiced in Recife city roads to slap the holes. The proposed model shows that it is viable and is not sensitive when varying input parameters, the results are easy to apply to the Recife city pavement maintenance industry including the model assumptions in "Operação Tapa-Buraco".
34

Metodologia de priorização de equipamentos medicos para programas de manutenção preventiva em hospitais

Ferreyra Ramirez, Ernesto Fernando 02 December 1996 (has links)
Orientador: Said Jorge Calil / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-07-21T20:43:49Z (GMT). No. of bitstreams: 1 FerreyraRamirez_ErnestoFernando_M.pdf: 4191425 bytes, checksum: f333b450c6c2fa05078c8f9cc47d9f7c (MD5) Previous issue date: 1996 / Resumo: Atualmente, as pressões para aumento da segurança e disponibilidade dos equipamentos médicos, e a limitação de recursos humanos e financeiros têm mostrado a necessidade de implantação de programas de manutenção preventiva. O alto custo deste tipo de manutenção obriga o desenvolvimento de programas que priorizem os equipamentos nos hospitais brasileiros. Este trabalho propõe uma metodologia para suprir esta necessidade. A metodologia proposta considera os fatores: I)Risco para o paciente e usuário do equipamento; 2)Importância estratégica do equipamento e Recomendações do fabricante e órgãos fiscalizadores; 3)Análise da viabilidade de manutenção preventiva; e 4)Análise periódica do histórico de falhas e consertos dos equipamentos. A estes fatores são atribuídos pontos, de modo a formar um número de prioridade (PE). Os resultados encontrados em um estudo de caso efetuado mostram que a metodologia é condizente com a realidade nacional devido à sua facilidade de implementação mesmo para o caso em que não haja dados anteriores sobre o histórico / Abstract: Nowadays, the increasing need of improving the safety and the availability of medical equipment, and the restrictions of human and financial resources have shown the importance of implementation of preventive maintenance programs. The high costs of this type of maintenance lead to the development of equipment prioritizing programs in the Brazilian hospitaIs. This work suggests a methodology to fuifiII this need. The proposed methodology considers the factors: 1) Physical Risk to the patient and to the user; 2) Equipment strategic importance and manufacturers' and accreditation entities recommendations; 3) Viability analysis of the preventive maintenance; and 4)Periodic analysis of the equipment failures and repair history. These factors receive ponderation in order to achieve an equipment priority number (PE). The results found in a case study showed the proposed methodology agrees with the national reality because it's easy to implement though the equipment maintenance history data were limited. / Mestrado / Engenharia Biomedica / Mestre em Engenharia Elétrica
35

Do not let bad maintenance ruin your day : A case study of coordinating turnaround maintenance in a continuous flow process industry.

Hlebnikovs, Andrew, Kövamees, Axel January 2022 (has links)
The uptime of machinery in continuous flow process industries such as steel manufacturing plants puts pressure on the maintenance function. This in turn contributes to sustaining reliable physical assets. As absence of reliable physical assets highly affects the competitive advantage. Turnaround maintenance is a common practice in such production setups and requires top-of-the-line managerial attention to be planned,executed and assessed in an efficient manner. By applying an abductive approach and combining the qualitative and quantitative research approaches, this thesis aims to explore the managerial issue of coordinating turnaround maintenance within a continuous flow process industry. The research questions that guide this thesis consist of describing how turnaround maintenance can be coordinated and its associated challenges. By comparing publicly available literature and empirical evidence provided by performing a case study, it is confirmed that the main challenges for conducting efficient turnaround maintenance comes down to the management in all stages associated with the turnaround. To coordinate turnaround maintenance activities in the most efficient manner, several challenges must be overcome. Aligning organisational goals and generating management commitment is the first prerequisite before any improvements can be done. It is necessary to define a common scope that strives for creating reliable physical assets to enhance the competitive advantage. The defined challenges in coordination are related to before, during and after the turnaround execution. These relate to creating a cyclical process for the turnaround where previously acquired knowledge is used for improving future turnarounds. While detailed planning is necessary for each turnaround, a high level of contingency is also necessary. To achieve this and succeed, it is argued that a high level of visibility during the turnarounds and the use of standardised methods is required. / Drifttiden för maskiner i industrier med kontinuerligt flöde, såsom ståltillverkningsanläggningar, sätter press på underhållsverksamenheten. Detta för att i sin tur bidra till att upprätthålla tillförlitliga fysiska tillgångar. Eftersom avsaknad av tillförlitliga fysiska tillgångar påverkar konkurrensfördelen i hög grad. Storaunderhållstopp där den kontinuerliga produktionslinan stoppas, är en vanligt förekommande praxis i sådana produktionsanläggningar vilket kräver ledningens uppmärksamhet för att planera och utvärdera på ett effektivt sätt. Genom att tillämpa ett abduktivt tillvägagångssätt och kombinera kvalitativ och kvantitativ forskningsmetodik, syftar detta examensarbete till att utforska den ledarskapsrelaterade frågan om att koordinera underhållsaktiviteter för stora underhållstopp inom processindustrier med kontinuerligt flöde. Forskningsfrågorna som vägleder detta examensarbete består av att beskriva hur större underhållstopp kan koordineras och dess associerade utmaningar. Genom att jämföra offentligt tillgänglig litteratur och empiriska bevis från en fallstudie, bekräftas att de största utmaningarna för att genomföra ett effektivt underhållstopp beror på ledningen i alla steg som är förknippade med underhållstoppet. För att samordna underhållsaktiviteterna på ett så effektivt sätt som möjligt måste flera utmaningar övervinnas. Att anpassa organisationens mål och skapa engagemang hos ledningen är den första förutsättningen innan fler förbättringar kan utföras. Det är nödvändigt att definiera gemensamma mål som strävar efter att skapa tillförlitliga fysiska tillgångar för att i sin tur öka konkurrensfördelen. De definierademanagementutmaningarna sammankopplas till före, under och efter underhållsstoppet. Utmaningarnahandlar om att skapa en cyklisk process för underhållsstoppen där tidigare förvärvad kunskap nyttjas för att förbättra framtida stopp. Även om detaljerad planering är nödvändig för varje underhållstopp, är en hög nivå av beredskap också nödvändig. För att uppnå och lyckas med detta krävs en hög grad av visibilitet under underhållsstoppen och användning av standardiserade metoder.
36

Continuous Preventive Bridge Maintenance : Effect of High Pressure Washing on Concrete Bridges

Andersson, Louise January 2022 (has links)
In Sweden, as in many other countries, preventive maintenance of structures andbridges is considered important. It provides several benefits such as prolonged lifespan or service life, less need for repair, and hopefully reduced costs and lowerenvironmental impact. A large part of Sweden’s bridge stock is getting quite old. The idea that small actionscan improve and/or prolong the status of the bridge and postpone needs for repairor prevent damage with a reduction in life cycle cost is generally in the owner’sinterest. One such preventive maintenance measure is the annual washing ofbridges. While clear positive effects have been observed on the expansion joints,drainage system, and the bridge’s visual appearance, an important question is howthe washing affects chloride ingress, mainly from de-icing salts, in reinforcedconcrete bridge members. The hypothesis is that the high-pressure washing cleansaway the contaminants on the surface and in the long run reduces the chloridecontent. While the practical experience has been positive in Sweden, no research hasyet been done concerning the effect of high-pressure washing on chloride ingress inconcrete bridges. A study has been conducted on the preventive bridge maintenance practice of theSwedish Transport Administration (STA) and Swedish municipalities. This work hasbeen based on a literature review, a survey of municipalities’ bridge maintenance,and practical participation with contractors during annual maintenance. Field andlaboratory tests were carried out on the effect of washing on chloride ingress in twotypes of concrete. A field station was installed on an edge beam of a bridge and wasfollowed over three years’ exposure including winter seasons, winter maintenance,and annual washing in June. Also, an accelerated test method was developed in thelaboratory to simulate the yearly exposure and test the effect of high- pressurewashing in a long-term simulation over just a few weeks. The practical aspects of bridge maintenance seem to be quite similar betweenSweden and in other countries. However, in terms of descriptions of and availablemeans for maintenance and repairs, there seem to be larger differences. For the fieldstation, the results after one year’s exposure do not show anything more than theanticipated difference in chloride ingress between the two concrete types understudy. For year two, a slight difference indicated that washed samples had a reducedchloride content. For year three, however, there was no distinct difference betweenivwashed and unwashed samples. The reasons for this need to be further investigatedand examined. This will be done in the continuous tests of field exposure. The laboratory test method has been developed and successively improved. The shape and levels of chloride ingress are reasonable and comparable with fieldsamples. However, there is a need to examine the effect of natural rain exposurewhich might have the same or greater effect of diluting the chloride content aswashing the surface once a year. Other factors also need to be considered, such aswhen and how often the maintenance is performed. A first step to be able to examinethis has been completed through the development of the accelerated test method. / I Sverige, som i många andra länder, anses förebyggande underhåll avkonstruktioner och broar vara viktigt. Det har flera fördelar, som att förlängalivslängden eller bruksskedet, minska behovet av reparationer och förhoppningsvisminska kostnader och miljöpåverkan. En stor del av Sveriges brobestånd börjar bli relativt gammalt. Det gör attförebyggande underhåll får mer uppmärksamhet och ges större vikt. Idén att mindreåtgärder kan förbättra och/eller förlänga standarden på bron och förskjuta behovetav reparationer eller förebygga skador med en minskning i livscykelkostnader ärgenerellt i ägarens intresse. En typ av förebyggande underhåll är den årligatvättningen av broar. Tydliga positiva effekter kan ses på fogar, dränering samt bronsvisuella intryck men en viktig fråga är hur tvättningen påverkar kloridinträngning från huvudsakligen tösalter i armerad betong. Hypotesen är att högtryckstvätt tarbort föroreningar på ytan, vilket på lång sikt minskar kloridmängden i betongen. Den praktiska erfarenheten ska ha varit positiv i Sverige, men ingen forskning har utförtspå vilken effekt högtryckstvättning har på kloridinträngningen i en bro av betong. En studie om det förebyggande brounderhållet hos Trafikverket och kommuner harutförts med hjälp av Trafikverkets och föregångarna Vägverkets dokument, annanlitteratur, en enkät till kommuner samt medverkan och observationer av detpraktiska vid utförandeentreprenaders årliga utförande av underhållet. Fält- ochlaboratorieprover för undersökning av tvättningens effekt på kloridinträngningenhar utförts. En fältstation på en kantbalk på en bro har installerats och följts undertre års exponering, med vinterklimat, vinterunderhåll samt årlig tvättning i juni. Enaccelererad provningsmetod har utvecklats för att simulera den årliga exponeringenoch undersöka effekterna av högtryckstvättning i en långtidssimulering på baranågra veckor. Ur praktisk synvinkel verkar brounderhåll vara ganska likt i Sverige och andraländer. Dock verkar beskrivningar och tillgängliga ekonomiska medel för underhålloch reparation visa större skillnader, vilket kan ha en stor påverkan på broarnasskadestatus. För fältstationen, är resultatet efter ett års exponering inte speciellttydligt förutom den förväntade skillnaden mellan de två undersökta betongtyperna(en äldre och en modern, mer beständig kvalitet). För år två syns en mindre skillnadmellan tvättade och otvättade prover. Skillnaden kan inte observeras i resultaten förår tre dock. Orsaken till detta måste undersökas vidare. Detta görs genom dekontinuerliga provningarna som fortsätter. Den accelererade provningsmetoden har utvecklats och kontinuerligt förbättrats.Formen och nivån på kloridinträngningen kan anses rimliga och jämförbara (påformen) med fältprover. Dock finns det ett behov av att undersöka påverkan avnaturligt regn vilket kanske har samma eller större effekt på att späda utkloridmängden som att högtryckstvätta ytorna en gång per år. Andra aspekterbehöver också undersökas, till exempel när och hur ofta underhållet ska utföras. Ettförsta steg att möjliggöra det har avslutats med utvecklingen av den accelereradeprovningsmetoden. / <p>QC 20220509</p> / Förebyggande Brounderhåll
37

Production management model based on lean manufacturing for cost reduction in the timber sector in Peru

Lastra, Fiorella, Meneses, Nicolás, Altamirano, Ernesto, Raymundo, Carlos, Moguerza, Javier M. 01 January 2019 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / At present, timber is the only commodity whose demand will increase at worldwide levels. Peru, despite being one of the countries with the highest forest potential, cannot compete with countries such as Brazil and China due to high production costs. Therefore, the aim of this article is to develop a production management model based on Lean Manufacturing techniques to increase production capacity by improving processes and reducing costs. For this, Knowledge Management, Change Management, and Production Management were implemented. The model was validated in a Peruvian timber company, where a 49% reduction in the cleaning and organization time was achieved. Calibration periods were reduced by 61%, and preventive maintenance periods by 72%.
38

Implementar Gestión del Mantenimiento para una flota de vehículos de una empresa de transporte de personas con operaciones en la sierra central del Perú / Implement Maintenance Management for a vehicle fleet of a transportation company of people with operations in the central highlands of Peru

Dávila Rojas, Nohely Cinthya 03 July 2020 (has links)
Turismo Dávila es una empresa de transporte terrestre con autorización para prestar servicio de transporte turístico y de personal a nivel nacional desde hace 5 años, en ese marco sus principales usuarios son trabajadores del sector minero. Dada la constante y creciente demanda de estos servicios, la empresa ha incrementado su flota de vehículos y ampliado su cartera de clientes. La clave para mantener y permitir el crecimiento del negocio está en brindar servicios de acuerdo a los requerimientos del cliente y con la menor siniestralidad, por eso es fundamental contar con una eficiente operatividad y disponibilidad de la flota de vehículos lo que no se está concretando en la realidad, allí parte el desarrollo de ésta investigación: plantear la implementación de una Gestión del Mantenimiento para los vehículos de la empresa de tal forma que estos puedan cumplir una función óptima bajo los parámetros solicitados y esperados por el cliente. / Turismo Dávila is a land transport company authorized to provide tourist transport service and personnel nationwide for 5 years, in this framework its main users are workers in the mining sector. Given the constant and growing demand for these services, the company has increased its vehicle fleet and expanded its client base. The key to maintaining and allowing the growth of the business is to provide services according to customer requirements and with the lowest accident rate, so it is essential to have an efficient operation and availability of the fleet of vehicles which is not being specified in the reality, there starts the development of this research: to propose the implementation of a Maintenance Management for the vehicles of the company in such a way that they can fulfill an optimal function under the parameters requested and expected by the client. / Trabajo de Suficiencia Profesional
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Analys av maskinstopp på pastermixer i linje två på Boliden Mineral AB / Analysis of machine stopp on pastemixer in line two at Boliden Mineral AB

Mirzajee, Nahid January 2020 (has links)
Boliden Mineral AB i Garpenberg är en av världens mest moderna gruvor som bedriver gruvdrift och anrikning av malm. I gruvan Garpenberg bryts komplexmalm, bland annat bly, zink, koppar, silver och guld. Då den så kallade pastermixern vid linje två kom i drift ibörjan av år 2019 har den haft störningar. Målet med projektet var att undersöka möjligheterna att öka driftsäkerheten vid pastermixern i linje två genom att ge förslag på hur man kan minimera de oplanerade maskinstoppen. Ett delmål var att ta fram förslag på rutiner för att få till en fungerande daglig tillståndskontroll under drift, detta för att kunna finna eventuella problem innan det leder till produktionsstopp. För att få en någorlunda rättvist bild av den problem som finns vid pastermixern i linje två genomfördes personliga intervjuer med personaler som dagligen arbetar med denna utrustning. Men även personal som har varit med under projektets gång, som en komplettering genomfördes observation av utrustningen vid ett tillfälle. Resultat av den datainsamling som har genomförts grundar sig i hög sträckning på kvalitativ undersökning och den erfarenhet som finns inom organisationen. Bland de analyserade störningar och fel som har funnits visade det sig att axelhaveriet orsakade mest problem i produktionen genom att ha tio dagars produktionsstopp. Grundorsaken har visat sig vara att underhållsorganisationen inte haft tillgång till leverantörens rekommenderade underhållsmanualer från start. Förutsättningarna för att skapa en bra FU-plan för pastermixern från början saknades. Införandet av subjektiva- objektiva tillståndskontroller är ett sätt att förebygga lager- och axelhaveri i framtiden. / Boliden Mineral AB in Garpenberg is one of the most modern mines in the world to conduct in mining and enrichment of ore, containing lead, zinc, silver and gold. When the so called pastemixer in line two came into operation at the beginning of year 2019, it contained with distraction. The main goal of the project was to investigate the possibilities of increasing dependability of pastermixern in line two by offering solution on how to minimize the unplanned machine stops. An partial goal was to suggest routines for condition monitoring in machinery, in order to identify a significant change before it leads to unexpected production stops. The method of reaching the project goal was first to conduct personal interviews with staff that works with this machine daily. But also staff who had been involved during the purchase of this equipment. To understand the situation and the problem better an observation took place. The result of the collected data showed that the breakdown of the axis caused the most problem in production by causing ten days of production stop. The root showed that the maintenance organization did not have access to the suppliers recommended maintenance manuals from the beginning. The prerequisite to provide an preventive maintenance plan for this equipment was missing from the beginning. By establishing routines for condition monitoring in machinery is a way to prevent bearingand shaft problems but also unplanned production stops in the future.
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[en] OPTIMIZATION OF THE PERIODICITY OF PREVENTIVE MAINTENANCE OF RAILWAY ASSETS / [pt] OTIMIZAÇÃO DA PERIODICIDADE DE MANUTENÇÃO PREVENTIVA DE ATIVOS FERROVIÁRIOS

AMANDA FATIMA FERREIRA E SOUSA 16 May 2023 (has links)
[pt] A manutenção tem relevante participação estratégica em uma companhia, fundamental para o sucesso das organizações, a atuação deste setor envolve a redução do tempo de máquinas paradas, contribuindo com a eficiência do processo e diminuição dos custos operacionais. A intervenção preventiva é um importante tipo de manutenção, seu propósito é diminuir as falhas fundamentada em um planejamento com intervalos definidos de tempo, no entanto, determinar o melhor período não é uma atividade trivial. O intuito deste trabalho é utilizar dos conceitos de programação matemática para formular um modelo que auxilie na definição de um cronograma de manutenção preventiva, visando encontrar o melhor intervalo de tempo para intervenção na máquina baseado em informações de custos, tempo de atendimento e capacidade de mão de obra. O modelo matemático foi aplicado ao ambiente ferroviário com a finalidade de certificar a viabilidade de utilização dos métodos de Pesquisa Operacional, os resultados obtidos comprovaram se tratar de uma boa ferramenta para aplicação. Frente ao modelo atual, o cronograma de manutenção preventiva desenvolvido neste trabalho proporcionou uma economia de 40 por cento para a companhia, além do aumento médio de 30 por cento de disponibilidade a cada trimestre das máquinas de modelo Socadora. / [en] Maintenance has a relevant strategic role in a company, fundamental to the success of organizations, the performance of this sector involves reducing the time of machine downtime, contributing to the efficiency of the process and reduction of operating costs. Preventive intervention is an important type of maintenance, its purpose is to reduce failures based on planning with defined time intervals, however, determining the best period is not a trivial activity. The purpose of this work is to use mathematical programming concepts to formulate a model that helps define a preventive maintenance schedule, aiming to find the best time interval for machine intervention based on cost information, service time and hand capacity. of work. The mathematical model was applied to the railway environment in order to certify the feasibility of using Operational Research methods, the results obtained proved to be a good tool for application. Compared to the current model, the preventive maintenance schedule developed in this work provided savings of 40 percent for the company, in addition to an average increase of 30 percent in availability each quarter of Socadora model machines.

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