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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.
11

Prototipagem rápida e ferramental rápido aplicados às peças utilizadas em ensaios estáticos de embalagens para acondicionamento e transporte de peças automotivas. / Rapid prototyping and rapid tooling applied parts used in in static tests of racks for packaging and transporting automobile parts.

Silva, Guilherme Canuto da 25 September 2008 (has links)
A necessidade deste trabalho se fez no setor de Planejamento de Fluxo de Materiais e Embalagens (PFME), que pertence ao departamento de engenharia de manufatura de uma filial de montadora instalada no Brasil. Neste setor existe a necessidade de se obter peças protótipo em um menor espaço de tempo possível para realização dos ensaios estáticos dos protótipos das embalagens especiais, uma vez que as embalagens precisam acondicionar as peças produzidas a partir da fase de preparação da produção em série do automóvel (pré-série ou PVS). Neste trabalho, a partir do estudo das tecnologias de Rapid Prototyping (RP) - Prototipagem Rápida (RP) e Rapid Tooling (RT) Ferramental Rápido (RT) é selecionada a técnica mais adequada para se atender às necessidades deste setor. Para isto, algumas condições de contorno foram consideradas: a aplicação das técnicas de RP e RT foram restringidas às peças externas do carro como portas, tampas dianteiras, traseiras e pára-lama e as fontes fornecedoras consultadas encontram-se no mercado doméstico. Com base em um estudo de caso pode-se validar esta proposta. Os resultados obtidos com a aplicação da técnica de ferramental rápido Vacuum Bagging foram uma redução média de 4,5 meses na obtenção das peças protótipo e uma redução global dos custos de aquisição de aproximadamente R$ 100.000,00. / The need of this work was made in the material flow planning and packing (PFME) section, that belongs to the manufacture engineering department of an assembler company installed in Brazil. In this sector, there is a growing need to obtain prototype parts in the shortest time possible in order to carry out static prototype tests of the special packing, since these racks need to be ready to assist the preparation phase of the series production of the vehicle (pre series or PVS). In this work, beginning from the study of Rapid Prototyping (RP) and Rapid Tooling (RT) technologies is selected the technique more adequate to assist to the needs of this section. For that purpose, some limiting conditions were considered: the application of the RP and RT techniques is limited to the external parts of the vehicle, such as doors, front and back hoods and fenders, and the consulted suppliers should be available in the domestic market. Based in a case study this proposal could be validated. The obtained results with the applied Rapid Tooling Vacuum Bagging technique were a medium reduction of 4,5 months in the prototype parts acquisition and a global reduction in the acquisition costs of approximately R$ 100.000,00.
12

Rapid Tooling and the LOMOLD Process

Joubert, Francois 12 1900 (has links)
Thesis (MScEng (Industrial Engineering))--University of Stellenbosch, 2005. / The LOMOLD process is a new plastic moulding process being researched at the University of Stellenbosch. The process essentially combines injection moulding and compression moulding. Molten plastic is forced into the mould cavity using a plunger. This plunger then forms part of the cavity wall. The plunger face must therefore follow the geometry of the part. Rapid Tooling evolved from Rapid Prototyping. There are two categories of Rapid Tooling: indirect and direct rapid tools. Indirect rapid tools are manufactured by using a master pattern to form the mould cavity. The accuracy of the mould cavity depends heavily on the accuracy of the master pattern. The master pattern is usually produced using Rapid Prototyping technology. Direct rapid tools use Rapid Prototyping technology to build the mould through and additive, layer by layer process or a subtractive process. This research investigates the use of Rapid Tools for the LOMOLD process. Aluminium Filled Epoxy Tooling (AFET) represents the indirect technology and CNC-machined tooling the direct technology. Both of these technologies are available at the University of Stellenbosch. Parts are manufactured on these tools using an experimental LOMOLD machine. These two technologies are compared in terms of part accuracy, tool lead time, tool cost and part cost. The research concluded that the only advantage the AFET has over the CNC-machined tool is a shorter manufacturing lead-time. In terms of tool cost, tool life, part geometric accuracy, part cost and cycle time the CNC tool is superior. Therefore the application of AFET is limited to small volume, prototype or pre-production runs for tool design confirmation, part functional testing and part appearance testing. It is also demonstrated that a cooling system on the AFET tool has no significant influence on the tool performance and should therefore, especially for production runs less than 150 parts, not be included in the tool to save on tool cost. Another conclusion is that the LOMOLD process is not consistent enough for a production process. This statement could be limited to the machine used for the research but to prove this statement wrong, the machine must be improved and more investigation is required.
13

Marknadsundersökning kring additiv tillverkning i Sverige / Market research on Additive Manufacturing in Sweden

Tavajoh, Sara, Michael, Huynh January 2018 (has links)
Användningen och intresset för additiv tillverkning (AM) har ökat markant de senaste åren och det finns en teori kring att tillverkningsmetoden kan vara det nästa steget i den industriella revolutionen. Eftersom AM fortfarande befinner sig i utvecklingsstatidet går det att anta att tekniken ännu inte uppnått sin fulla potential och att det kan komma att finnas möjligheter att implementera tekniken i fler branscher och företag. Detta skulle innebära en bredare marknad för AM. Syftet med examensarbetet var att undersöka vilka möjligheter och hinder som finns för ökad användning av AM i Sverige. Studien genomfördes genom kvalitativa intervjuer med åtta olika verksamheter tillhörande den svenska industrin och en litteraturgenomgång för att presentera nuläget för AM i svensk industriell marknad. Resultatet av datainsamlingen analyserades med modellerna PEST, 4P och slutligen SWOT. De fördelar som har setts med användningen av AM har varit minskade ledtider, minskade kostnader för tillverkning av produkter och verktyg, minskat materialspill och en optimal designprocess med ökad kreativitet. De begränsningar som finns i tekniken i dagsläget är att priset för material och maskiner är dyrt. Vidare anses även kvalitet på slutdetalj, begränsad byggvolym och opålitliga processer vara problematiska. De möjligheter som finns beror huvudsakligen på den forskning som görs. Förutsättningarna för AM i svensk industri kommer att bero på hur tekniken kommer att utvecklas. De hinder som finns är kopplat till kompetensbrist och att det inte finns befintliga standarder för material eller process inom AM. / Within the industrial sector, an increased interest and usage of Additive Manufacturing (AM) throughout the decade has been formed. The layer-upon-layer building technology has been seen and recognized as one of the next industrial revolutionizing methods of production. As the technology is still in the trending and uprising phase it should be considered that its full potential has not yet been achieved, as large opportunities for implementation of AM exist and that new companies and markets have a growing interest in this technology. Through this study a market research was conducted to identify and present what opportunities and obstacles there are for an increased usage of AM in Sweden. A literature study on the Swedish market has been made to present the market as of today. Eight qualitative interviews have also been conducted with companies within the industrial sector to identify the areas of use within AM for production. The concepts and models used to analyze these questions was PEST, Marketing Mix and SWOT. The concluded results for advantages in using AM are shortened lead times, reduced costs of production of components and tools, reduced material waste and optimization of design processes with increased creativity. The concluded challenges are expensive materials and machine, the quality of finished components, limited printing volume due to the 3D-printers and reliability of printing processes. The finalized opportunities that are presented in this work are that AM is dependent on how much research on the subject and factors around it is done. How AM will be applied in the coming future revolves around the advancement in the technology. The obstacles that are found in this study are lack of competence and lack of standard for materials and processes within AM.
14

Prototipagem rápida e ferramental rápido aplicados às peças utilizadas em ensaios estáticos de embalagens para acondicionamento e transporte de peças automotivas. / Rapid prototyping and rapid tooling applied parts used in in static tests of racks for packaging and transporting automobile parts.

Guilherme Canuto da Silva 25 September 2008 (has links)
A necessidade deste trabalho se fez no setor de Planejamento de Fluxo de Materiais e Embalagens (PFME), que pertence ao departamento de engenharia de manufatura de uma filial de montadora instalada no Brasil. Neste setor existe a necessidade de se obter peças protótipo em um menor espaço de tempo possível para realização dos ensaios estáticos dos protótipos das embalagens especiais, uma vez que as embalagens precisam acondicionar as peças produzidas a partir da fase de preparação da produção em série do automóvel (pré-série ou PVS). Neste trabalho, a partir do estudo das tecnologias de Rapid Prototyping (RP) - Prototipagem Rápida (RP) e Rapid Tooling (RT) Ferramental Rápido (RT) é selecionada a técnica mais adequada para se atender às necessidades deste setor. Para isto, algumas condições de contorno foram consideradas: a aplicação das técnicas de RP e RT foram restringidas às peças externas do carro como portas, tampas dianteiras, traseiras e pára-lama e as fontes fornecedoras consultadas encontram-se no mercado doméstico. Com base em um estudo de caso pode-se validar esta proposta. Os resultados obtidos com a aplicação da técnica de ferramental rápido Vacuum Bagging foram uma redução média de 4,5 meses na obtenção das peças protótipo e uma redução global dos custos de aquisição de aproximadamente R$ 100.000,00. / The need of this work was made in the material flow planning and packing (PFME) section, that belongs to the manufacture engineering department of an assembler company installed in Brazil. In this sector, there is a growing need to obtain prototype parts in the shortest time possible in order to carry out static prototype tests of the special packing, since these racks need to be ready to assist the preparation phase of the series production of the vehicle (pre series or PVS). In this work, beginning from the study of Rapid Prototyping (RP) and Rapid Tooling (RT) technologies is selected the technique more adequate to assist to the needs of this section. For that purpose, some limiting conditions were considered: the application of the RP and RT techniques is limited to the external parts of the vehicle, such as doors, front and back hoods and fenders, and the consulted suppliers should be available in the domestic market. Based in a case study this proposal could be validated. The obtained results with the applied Rapid Tooling Vacuum Bagging technique were a medium reduction of 4,5 months in the prototype parts acquisition and a global reduction in the acquisition costs of approximately R$ 100.000,00.
15

An Exploration of Rapid Tooling in Low-Cost Bead Foam Molding Applications

Dejager, Matthew Emerson 07 February 2024 (has links)
Many manufacturing processes require complex tooling which contributes significantly to the cost and time required to develop new products. Bead foam molding is often hampered by these limitations. This thesis presents an analysis of Additive Manufacturing (AM) applications in low cost bead foam molding, focusing on molding trials, economic analysis, and future potential. Through molding trials, the thesis evaluates the efficacy of AM tooling in comparison to traditional aluminum tooling, specifically in evaluating tool life and cost. A key finding is a reduction in lead time up to 70% and cost of up to 63% compared to traditional tooling, particularly in low-volume production scenarios. This thesis includes a detailed cost analysis, which breaks down the cost components associated with AM processes such as pre-processing, production, material costs, post-processing, and overheads. This analysis reveals that AM tooling can offer substantial cost savings over conventional methods, making it a viable option for specific manufacturing contexts. Findings suggest that while AM tooling shows significant promise in reducing costs and accelerating production in bead foam molding, further research is required. This research should focus on exploring the scalability of AM for larger tools and investigating the application of new and emerging AM processes and materials. / Master of Science / This thesis explores the use of Additive Manufacturing (AM), often known as 3D printing, in creating molds for bead foam molding—a process used in manufacturing a variety of foam products. Findings reveal that using AM for toolmaking can be faster and more cost-effective than traditional methods, especially for small-scale production. The thesis details experiments comparing AM with conventional tooling and presents a cost analysis showing the potential time and cost savings. While promising, further research is needed to fully harness the benefits of AM in this field. This study opens doors to more efficient and economical manufacturing techniques using emerging AM technology.
16

Examination of Rapid Prototype Tooling

Grunden, Eric Hans 30 August 2016 (has links)
No description available.
17

Ejection forces and static friction coefficients for rapid tooled injection mold inserts

Kinsella, Mary E. 29 September 2004 (has links)
No description available.
18

Tool manufacturing by metal casting in sand moulds produced by additive manufacturing processes

Nyembwe, Kasongo Didier January 2012 (has links)
Thesis (D. Tech. ( Mechanical Engineering )) - Central University of technology, Free State, 2012 / In this study an alternative indirect Rapid Tooling process is proposed. It essentially consists of producing sand moulds by Additive Manufacturing (AM) processes followed by casting of tools in the moulds. Various features of this tool making method have been investigated. A process chain for the proposed tool manufacturing method was conceptually developed. This process chain referred to as Rapid Casting for Tooling (RCT) is made up of five steps including Computer Aided Design (CAD) modeling, casting simulation, AM of moulds, metal casting and finishing operations. A validation stage is also provided to determine the suitability of the tool geometry and material for RCT. The theoretical assessment of the RCT process chain indicated that it has potential benefits such as short manufacturing time, low manufacturing cost and good quality of tools in terms of surface finish and dimensional accuracy. Focusing on the step of AM of the sand moulds, the selection of available AM processes between the Laser Sintering (LS) using an EOSINT S 700 machine and Three Dimensional Printing using a Z-Corporation Spectrum 550 printer was addressed by means of the Analytic Hierarchy Process (AHP). The criteria considered at this stage were manufacturing time, manufacturing cost, surface finish and dimensional accuracy. LS was found to be the most suitable for RCT compared to Three Dimensional Printing. The overall preferences for these two alternatives were respectively calculated at 73% and 27%. LS was then used as the default AM process of sand moulds in the present research work. A practical implementation of RCT to the manufacturing of foundry tooling used a case study provided by a local foundry. It consisted of the production of a sand casting pattern in cast iron for a high pressure moulding machine. The investigation confirmed the feasibility of RCT for producing foundry tools. In addition it demonstrated the crucial role of casting simulation in the prevention of casting defects and the prediction of tool properties. The challenges of RCT were found to be exogenous mainly related to workmanship. An assessment of RCT manufacturing time and cost was conducted using the case study above mentioned as well as an additional one dealing with the manufacturing of an aluminium die for the production of lost wax patterns. Durations and prices of RCT steps were carefully recorded and aggregated. The results indicated that the AM of moulds was the rate determining and cost driving step of RCT if procurement of technology was considered to be a sunk cost. Overall RCT was found to be faster but more expensive than machining and investment casting. Modern surface analyses and scanning techniques were used to assess the quality of RCT tools in terms of surface finish and dimensional accuracy. The best surface finish obtained for the cast dies had Ra and Rz respectively equal to 3.23 μm and 11.38 μm. In terms of dimensional accuracy, 82% of cast die points coincided with die Computer Aided Design (CAD) data which is within the typical tolerances of sand cast products. The investigation also showed that mould coating contributed slightly to the improvement of the cast tool surface finish. Finally this study also found that the additive manufacturing of the sand mould was the chief factor responsible for the loss of dimensional accuracy. Because of the above, it was concluded that light machining will always be required to improve the surface finish and the dimensional accuracy of cast tools. Durability was the last characteristic of RCT tools to be assessed. This property was empirically inferred from the mechanical properties and metallographic analysis of castings. Merit of durability figures of 0.048 to 0.152 were obtained for the cast tools. It was found that tools obtained from Direct Croning (DC) moulds have merit of durability figures three times higher than the tools produced from Z-Cast moulds thus a better resistance to abrasion wear of the former tools compared to the latter.
19

The impact of additive fabrication technologies on Institutional Research Development and the SA product development community-the CRPM story

De Beer, D.J. January 2008 (has links)
Published Aticle / The Centre for Rapid Prototyping and Manufacturing (CRPM) made a humble start in 1997 as a spin-off from a proposed research activity in 1995, at a stage when Technikons were still being seen as occupational training institutions rather than higher education institutions and and as such, were not funded for research. Addressing an area of high importance to the South African industry, the research activity soon grew into a research unit, commercial centre / centre of excellence, technology transfer unit and innovation support centre. Above all, the research started to impact on product development practices to deliver improved products. The paper considers the development of the available technology platforms at the CUT'S CRPM to become a technology power-house on the African continent, and how it impacted on Institutional Research Development in South Africa.
20

Characterization of metal powder based rapid prototyping components with respect to aluminium high pressure die casting process conditions

Pereira, M.F.V.T., Williams, M., Du Preez, W.B January 2010 (has links)
Published Article / This paper is based on tests performed on die component specimens manufactured by EOS-DMLS (direct metal laser sintering) and LENS (laser engineered net shape) RP (rapid prototyping) technology platforms, as well as manufactured specimens machined out of preferred standard hot work steel DIN 1.2344. These specimens resemble typical components used in metal high pressure die casting tool sets. The specimens were subjected to a programme of cyclic immersion in molten aluminium alloy and cooling in water-based die release medium. The heat checking and soldering phenomena were analyzed through periodic inspections, monitoring crack formation and evidence of surface washout. At the end of the thermal tests, mechanical strength and hardness tests were performed to assess toughness and core resistance variations in relation to the initial conditions. Finally metallographic investigations were performed through optical microscopy on all the specimens considered. The outcomes of this research will be presented and used by the CSIR for further development and application of the assessed EOS-DMLS and LENS rapid prototyping technologies in rapid die manufacturing techniques and die design principles, including time and economic feasibility criteria to be applied when considering rapid die manufacture.

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