O objetivo principal da tese foi desenvolver um método multicriterial de seleção de processos de fundição de metais (MMSPF) para fabricação de componentes, considerando-se critérios técnicos, ambientais e econômicos para ser aplicado nas fases iniciais do desenvolvimento do componente. O MMSPF é constituído pelos módulos de seleção técnica e econômica. O módulo de seleção técnica é destinado a antecipar as atividades de seleção de processos, a serem desenvolvidas na fase de projeto preliminar, enquanto o módulo de seleção econômica é destinado a antecipar as atividades de seleção de processos, necessárias à fase de projeto detalhado. O MMSPF realiza a seleção de processos de forma sequencial. Inicialmente, avaliando aspectos técnicos e, posteriormente, considerando aspectos econômicos. O MMSPF contempla as seis classes de ligas metálicas mais utilizadas na produção de componentes fundidos: aços, ferros fundidos, ligas de alumínio, ligas de cobre, ligas de magnésio e ligas de zinco, apropriadas aos processos de fundição de metais destinados à produção de peças. O MMSPF contempla os quinze principais processos de fundição de metais destinados a produção de peças: areia verde – manual (P1), areia verde – mecanizada (P2), areia verde – automatizada (P3), areia silicato - CO2 (P4), areia com resina – cura frio (P5), areia com resina – shell molding (P6), processo molde de gesso – plaster molding (P7), processo molde cerâmico (P8), investment casting (P9), molde cheio - lost foam (P10), fundição centrífuga - molde metálico (P11), molde permanente – gravidade (P12), molde permanente - baixa pressão (P13), fundição sob pressão - die casting (P14) e squeeze casting (P15) como conjunto solução da seleção. As inovações propostas pelo MMSPF foram: (i) consolidação das diferentes fontes de informação dos processos a serem utilizadas no MMSPF, por meio de uma função de agregação; (ii) utilização de aspectos ambientais como critérios para seleção de processos de fundição de metais; (iii) consideração da estimação de custos de fabricação para realizar a seleção de processos de fundição de metais a partir de um índice de custo de fabricação, relativo ao desempenho técnico. Também foi desenvolvido um aplicativo computacional para implementar o MMSPF composto por três elementos principais: um software de planilha eletrônica (Microsoft Excel), no qual são realizadas todas as operações matemáticas necessárias ao desenvolvimento das etapas operacionais do MMSPF; um banco de dados, o software livre SQLite, responsável por armazenar as informações utilizadas no aplicativo computacional do MMSPF; e a interface gráfica do usuário, que atua como elemento de conexão entre o banco de dados, o software de planilha eletrônica e o usuário. / The main objective of this thesis was to develop a Multi-criteria Method for metal Casting Process Selection (MMCPS) to manufacturing components, considering technical criteria, environmental and economic to be applied in the early stages of design of the component. The MMCPS consists modules for the technical and economic selection. The technique selection module is designed to anticipate the activities of processes selection to be developed in the embodiment design, while the economic selection module is designed to anticipate selection process activities, necessary the detailed design phase. The MMCPS conducts the selection process sequentially. Initially, evaluating technical aspects and, subsequently, considering economic aspects. The MMCPS includes the six classes of metal alloys more used in the production of cast components: steel, cast iron, aluminum alloys, copper alloys, magnesium alloys and zinc alloys, suitable for metal shape casting processes. The MMCPS covers the fifteen main metal shape casting processes: green sand – hand molding (P1), green sand – mechanized molding (P2), green sand - automatic molding (P3), silicate-CO2 (P4), air-set/nobake (P5), shell molding (P6), plaster molding (P7), ceramic mold (P8), investment casting (P9), lost foam (P10), centrifugal casting – metallic mold (P11), permanent mold-gravity (P12), permanent mold-low pressure (P13), die casting (P14) and squeeze casting (P15) as the set solution for the selection process. The innovations proposed by MMCPS were: (i) consolidation of different sources of information processes to be used in MMCPS through an aggregation function; (ii) use of environmental aspects as criteria for selection of metal casting processes; (iii) consideration of the cost estimation of manufacturing to make the metal casting process selection from an index of manufacturing cost on the technical performance. Also developed a computational tool to implement the MMCPS composed of three main elements: a spreadsheet software (Microsoft Excel), which are held every mathematical operations necessary for the development of operational steps MMCPS; a database, freeware SQLite, responsible for storing information used in the application of computational MMCPS, and the graphical user interface, which acts as a link between the database, the spreadsheet software and the user.

O objetivo principal da tese foi desenvolver um método multicriterial de seleção de processos de fundição de metais (MMSPF) para fabricação de componentes, considerando-se critérios técnicos, ambientais e econômicos para ser aplicado nas fases iniciais do desenvolvimento do componente. O MMSPF é constituído pelos módulos de seleção técnica e econômica. O módulo de seleção técnica é destinado a antecipar as atividades de seleção de processos, a serem desenvolvidas na fase de projeto preliminar, enquanto o módulo de seleção econômica é destinado a antecipar as atividades de seleção de processos, necessárias à fase de projeto detalhado. O MMSPF realiza a seleção de processos de forma sequencial. Inicialmente, avaliando aspectos técnicos e, posteriormente, considerando aspectos econômicos. O MMSPF contempla as seis classes de ligas metálicas mais utilizadas na produção de componentes fundidos: aços, ferros fundidos, ligas de alumínio, ligas de cobre, ligas de magnésio e ligas de zinco, apropriadas aos processos de fundição de metais destinados à produção de peças. O MMSPF contempla os quinze principais processos de fundição de metais destinados a produção de peças: areia verde – manual (P1), areia verde – mecanizada (P2), areia verde – automatizada (P3), areia silicato - CO2 (P4), areia com resina – cura frio (P5), areia com resina – shell molding (P6), processo molde de gesso – plaster molding (P7), processo molde cerâmico (P8), investment casting (P9), molde cheio - lost foam (P10), fundição centrífuga - molde metálico (P11), molde permanente – gravidade (P12), molde permanente - baixa pressão (P13), fundição sob pressão - die casting (P14) e squeeze casting (P15) como conjunto solução da seleção. As inovações propostas pelo MMSPF foram: (i) consolidação das diferentes fontes de informação dos processos a serem utilizadas no MMSPF, por meio de uma função de agregação; (ii) utilização de aspectos ambientais como critérios para seleção de processos de fundição de metais; (iii) consideração da estimação de custos de fabricação para realizar a seleção de processos de fundição de metais a partir de um índice de custo de fabricação, relativo ao desempenho técnico. Também foi desenvolvido um aplicativo computacional para implementar o MMSPF composto por três elementos principais: um software de planilha eletrônica (Microsoft Excel), no qual são realizadas todas as operações matemáticas necessárias ao desenvolvimento das etapas operacionais do MMSPF; um banco de dados, o software livre SQLite, responsável por armazenar as informações utilizadas no aplicativo computacional do MMSPF; e a interface gráfica do usuário, que atua como elemento de conexão entre o banco de dados, o software de planilha eletrônica e o usuário. / The main objective of this thesis was to develop a Multi-criteria Method for metal Casting Process Selection (MMCPS) to manufacturing components, considering technical criteria, environmental and economic to be applied in the early stages of design of the component. The MMCPS consists modules for the technical and economic selection. The technique selection module is designed to anticipate the activities of processes selection to be developed in the embodiment design, while the economic selection module is designed to anticipate selection process activities, necessary the detailed design phase. The MMCPS conducts the selection process sequentially. Initially, evaluating technical aspects and, subsequently, considering economic aspects. The MMCPS includes the six classes of metal alloys more used in the production of cast components: steel, cast iron, aluminum alloys, copper alloys, magnesium alloys and zinc alloys, suitable for metal shape casting processes. The MMCPS covers the fifteen main metal shape casting processes: green sand – hand molding (P1), green sand – mechanized molding (P2), green sand - automatic molding (P3), silicate-CO2 (P4), air-set/nobake (P5), shell molding (P6), plaster molding (P7), ceramic mold (P8), investment casting (P9), lost foam (P10), centrifugal casting – metallic mold (P11), permanent mold-gravity (P12), permanent mold-low pressure (P13), die casting (P14) and squeeze casting (P15) as the set solution for the selection process. The innovations proposed by MMCPS were: (i) consolidation of different sources of information processes to be used in MMCPS through an aggregation function; (ii) use of environmental aspects as criteria for selection of metal casting processes; (iii) consideration of the cost estimation of manufacturing to make the metal casting process selection from an index of manufacturing cost on the technical performance. Also developed a computational tool to implement the MMCPS composed of three main elements: a spreadsheet software (Microsoft Excel), which are held every mathematical operations necessary for the development of operational steps MMCPS; a database, freeware SQLite, responsible for storing information used in the application of computational MMCPS, and the graphical user interface, which acts as a link between the database, the spreadsheet software and the user.

Orientador: Maria Helena Robert / Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-18T15:19:59Z (GMT). No. of bitstreams: 1 Pinheiro_FrancioniGomes_M.pdf: 4724053 bytes, checksum: 96f025d7f0e3e288c1b9b2379de497e9 (MD5) Previous issue date: 2011 / Resumo: Este trabalho tem por objetivo avaliar a viabilidade técnica da fabricação e utilização do componente de motor (espaçador do ventilador) empregando tecnologia de materiais celulares. Foi empregado processo de tixoinfiltração em pré-formas pós-removíveis de NaCl em estado livre, tendo como matéria prima a mesma liga A356.0 da peça atual (fabricada por fundição convencional). Foi projetada e construída uma nova matriz metálica para se adaptar ao novo tipo de processo. Foram analisados parâmetros de processo como a granulometria do agente bloqueador (NaCl), a proporção da liga e do agente bloqueador e a distribuição de massa do alumínio disposto na matriz. Análises da qualidade dos componentes porosos e dos benefícios na manufatura demonstraram que o processo de tixoinfiltração é tecnicamente viável, com a obtenção de produtos com peso da ordem de 50% do peso do produto convencional, e dimensões finais adequadas, eliminando processos de usinagem e reduzindo tempo de fabricação do componente. Testes de montagem e funcional demonstraram bom desempenho quando submetido às condições de compressão exercidas na montagem e em teste preliminar em motor em funcionamento. Conclui-se que o processo é viável, que produtos mais leves podem ser obtidos em menor tempo de fabricação, mas ajustes visando maior resistência à compressão são necessários e servem como sugestão para futuros estudos / Abstract: This study aims to evaluate the feasibility of the manufacturing and utilization of an engine component (spacer fan) produced by cellular materials technology. The process used was thixoinfiltration of the alloy A356.0 into pre-forms of loose NaCl particles. This alloy is currently used for the production of the conventional cast parts. It was design and built a new metallic tooling to fit the new process. Process parameters were analyzed as the particle size of the space holder (NaCl), the ratio of metal/space holder weight content and the alloy mass distribution inside the metallic tooling. Analysis of the quality of porous parts produced and the benefits in the new process for their manufacture showed that the thixoinfiltration process is technically feasible, resulting products with 50% lowest weight if compared with current cast part and with near net shape, eliminating machining operations and reducing the manufacturing time. Assembly and functional tests showed good performance of the porous part when submitted to conditions of compression, due to assembly and preliminary engine running test. It is possible to conclude that the thixoinfiltration process is feasible, lighter products with reduced manufactuing time can be obtained, but further process adjustments to aim compression resistance are necessary and it is left here as a suggestion for future studies / Mestrado / Manufatura / Mestre em Engenharia Automobilistica

For over 30 years research has been done concerning the solidification and quenching of light metal alloys for the purpose of improving material properties. This thesis is concerned with an interesting new process for casting metals, by spraying water onto a sand mould, removing the sand and the directly quenching the part. This process is challenging since the component during solidification is extremely fragile, and the rate of cooling that is needed could seriously damage it. The water flow rate to the component needs to be quickly and precisely controlled. Additionally as this a new method there is very little prior art. The purpose of this thesis to develop a control system for the water sprayers flow rates. With this system the flow rate through the nozzles will be controlled indirectly using pressure feedback. The material properties and casting process, and how they influenced the design and construction of the spraying apparatus, are explained first. The hydraulic plant being controlled consists of three proportional valves connected to six spray nozzles. Based on experiments, the plant is extremely nonlinear making it difficult to control. Several controllers were developed and compared experimentally. The best performance was produced by extending a proportional plus integral plus derivative controller by adding an empirical nonlinear feedforward component; smoothing the setpoint; bounding the integration term; adding one bias at time zero and a 2nd bias for the remaining time (to mitigate valve stiction and to prime the hoses). This extended PID controller produced a 0.7% mean error and 1.9% mean absolute error for a multi-step setpoint covering a range of 0 to 80 PSI. Its performance was also highly repeatable. The standard deviations of the mean error, mean absolute error and maximum absolute error were less than 0.2 PSI over five runs. / Thesis / Master of Applied Science (MASc) / During the sand casting of aluminium and magnesium rapid cooling will greatly improve the material properties. By containing the liquid metal in a water soluble sand mould, and spraying it with water; the desired part shape and rapid cooling can be achieved. Removing the mould requires a powerful high flow rate jet. During the solidification of the metal, the flow rate must be reduced or the part would be demolished. This necessitated the development of a high speed, high flow rate controller to adjust the flow rate to remove the sand but not damage the part, and to maintain a smooth continuous cooling rate. The hydraulic system being controlled consists of three electronic valves connected to six spray nozzles. Several controllers are developed and compared experimentally. The best controller is shown to provide a quick and precise response.

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Daily life of our societies is strongly linked with the usage of natural resources. However, the vital resources of our planet especially energy is a limited resource. The energy consumption in the manufacturing industry is increasing and becoming noticeable; moreover it is being consumed in ways that can’t be sustained. There is great concern about minimizing the consumption of energy usage in the manufacturing industry and sustaining the natural carrying capacity of the ecosystem as well. This is one of the important challenges in today’s industrial world. This research work looks into one of the energy intensive manufacturing processes i.e. the casting process in automotive industry. Here the casting process for cylinder head manufacturing at one of the manufacturing plant in Europe is studied for identifying the most energy intensive steps namely melting, holding and pouring. Parameters that influence these steps and the relationships for energy consumption and dissipation have also been identified through extensive literature survey. By applying system dynamics modeling and simulation approach the interaction between each parameter in the overall process is analyzed in regard to energy consumption. By varying values of the parameters that have the highest impact in the process, the breakthrough opportunities that might dramatically reduce energy consumption during melting and holding have been explored, and potentially energy-saving areas based on the findings have also been identified. The output from this research work enables the company to identify potential avenues to optimize energy usage in the production and hence sustain its manufacturing.

Foundry is an industry that is both very old and very forward-looking. It is an essential base for several industrial sectors in today’s world. However, the metal casting industry faces a lot of challenges, including quality. There is a need for a converging system that orients all the resources towards meeting the quality requirements throughout the whole process. Zero Defect Manufacturing (ZDM) is a concept that aims to meet this need by adopting the four strategies of Detection, Prevention, Prediction and Repair. In that context, ZDM has been a subject of several collaborations between industrial sectors and the scientific community given its importance to the industrial field. Nevertheless, there is a lack of research into the implementation of this concept in certain types of industries, such as foundries. This thesis aims to fill this gap by presenting a generic review and a better understanding of the implementation of the ZDM approach in foundries. A systematic literature study has been conducted and the result has been compared to the empirical data collected via interviews with managers working in the metal casting industry. It was found that the nine key enablers of ZDM implementation in foundries are 1) Sensors & embedded systems, 2) AI & DigitalTwins, 3) Advanced robotics, 4) Connectivity & mobility, 5) Cloud computing, 6) Edge computing, 7) Forecasting & Modelling, 8) Business Solutions, 9) Intelligence & control systems. Automation enhances ZDM in foundries by enabling continuous and consistent data collection throughout the whole process. Ensuring skilled labour in specific disciplines such as PLC programming and statistics is seen to be a major challenge for foundries. At the end of the thesis, propositions for future studies in the field of ZDM in foundries and the role of future technologies, such as metal 3D printing, are proposed.

Companies strive to optimize their processes to increase productivity, efficiency, and quality in the production system. The complexity of different operations in a production system can vary, the level of complexity impacts the automation approach. The requirements of an automated solution increases with the level of complexity. A vision system is a type of automation solution which can improve the quality inspection process in many companies where the inspection process is performed manually. A challenge with implementing a vision system in different industries is that there are no general solutions. Depending on the requirements of an industry, the implementation of a vision system needs to be tailored to suit that industry. In this thesis, a case study is conducted in a foundry setting where empirical data is gathered through observations and interviews conducted with several departments. Nine parameters are identified which can affect the performance of a vision system in a metal casting environment. The identified parameters are analysed using relevant literature to find possible solutions. The result of the analysis is a set of guidelines which can be used when implementing vision systems in the metal casting industry and aims to mitigate possible negative effects of each parameter. A conceptual layout of a vision cell used to inspect cylinder heads based on the guidelines is also presented.

Three-dimensional (3D) laser scanners are becoming increasingly more affordable and user-friendly, making 3D-modeling tools more widely available to researchers in various countries and disciplines. In archaeology, 3D-modeling has the particular advantages of facilitating the documentation and analysis of objects that are fragile, rare, and often difficult to access. We have previously shown that 3D-modeling is a highly useful tool for shape analysis of archaeological bone material, due to the high measurement accuracy inherent in the latest generation of 3D laser scanners (Sholts et al. 2010; 2011). In this work, we explore the utility of 3D-modeling as a tool for Viking Age artefact analysis. To test the usefulness of 3D-modeling when analyzing artefacts with a very complex morphology, we chose highly ornate Viking Age baroque shaped brooches as study objects. These baroque shaped brooches constitute a group of dress ornaments mainly encountered in eastern Viking Age Scandinavia. Due to their large cast and/or attached bosses they obtain an almost baroque appearance, hence their name (cf. Jansson 1984: p. 81). They appear in two major versions, i.e. circular or equal armed, and in two kinds of material, i.e. silver- and copper-based alloys. Because of the position of bronze brooches in burial contexts, it appears they were used to fasten the cape or shawl in the female dress (cf. Jansson 1984: p. 75ff., Aagård 1984: p. 96ff.; Neiß 2006, figs. 3, 4; Capelle 1962: p. 106). For the present work a recently excavated brooch from Denmark was analyzed, together with three Russian brooches with nearly iconic status in the field of Viking Age studies. In the three case studies, we investigated possible uses of 3D-modeling for artefact analysis, artefact reconstruction, and tool mark and motif analysis. Exploring the usefulness of 3D-modeling for these purposes allowed us to draw conclusions regarding how 3D-analysis can be best incorporated into future artefact analysis. In addition, the case studies allowed us to gain new insights about the baroque shaped brooches and their uses. / <p>Forskningsfinansiärer: Helge Ax:son Johnsons stiftelse, Svenska institutet (Visby-programmet), Kungliga vitterhets historie och antikvitets akademin (Montelius minnesfond); Svenska fornminnesforeningen</p> / 3D-laserskanning som verktyg vid vikingatidsstudier