846 resultados para Machinery -- Manufacturing processes
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Presents a composite formed by orthophthalic resin and fiber loading of carnauba straw. The fibers were first dried in direct sun exposure and subsequently ground into fodder for the reduction in size. Various formulations of the composite were preliminarily tested by choosing the one presenting the best processability in applying the mold. The composite produced is used for the manufacture of a parabolic surface subsequently coated with mirror segments, flexible plastic, for reflecting the solar rays incident on it. The reflective parable represents the main element of the solar cooker that works with the concentration of sunlight and has dimensions of 1.14 m in diameter and area of 1.0 m². Manufacturing processes and assembly of solar cooker concentration produced are presented. The results of tests for cooking and baking various foods, including rice, pasta, beans, cake, cassava, shrimp, beef, breaded demonstrating the competitiveness of solar cooker studied with other stoves already manufactured and tested in Brazil are presented and in the world. It was also demonstrated the feasibility of the proposed composite for Prototypes manufacture of solar and other structures that do not require great efforts resistance
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Polyurethanes are very versatile macromolecular materials that can be used in the form of powders, adhesives and elastomers. As a consequence, they constitute important subject for research as well as outstanding materials used in several manufacturing processes. In addition to the search for new polyurethanes, the kinetics control during its preparation is a very important topic, mainly if the polyurethane is obtained via bulk polymerization. The work in thesis was directed towards this subject, particularly the synthesis of polyurethanes based castor oil and isophorone diisocianate. As a first step castor oil characterized using the following analytical methods: iodine index, saponification index, refraction index, humidity content and infrared absorption spectroscopy (FTIR). As a second step, test specimens of these polyurethanes were obtained via bulk polymerization and were submitted to swelling experiments with different solvents. From these experiments, the Hildebrand parameter was determined for this material. Finally, bulk polymerization was carried out in a differential scanning calorimetry (DSC) equipment, using different heating rates, at two conditions: without catalyst and with dibutyltin dilaurate (DBTDL) as catalyst. The DSC curves were adjusted to a kinetic model, using the isoconversional method, indicating the autocatalytic effect characteristic of this class of polymerization reaction
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Atualmente a preocupação ambiental está fazendo com que as empresas busquem diminuir os impactos ambientais por elas causados, ao mesmo tempo em que melhoram a qualidade do produto e processos de fabricação. Logo, muitas pesquisas estão sendo desenvolvidas na área de usinagem para se analisar o real dano ao meio ambiente quando usados diferentes métodos de lubri-refrigeração. Este trabalho teve como objetivo analisar a qualidade da peça produzida e o desgaste do ferramental de corte de uma retificadora plana ao se usinar cerâmica de alumina com dois métodos distintos de aplicação de fluido de corte: método convencional com vazão de 458,3 mL/h e o método da mínima quantidade de lubrificação (MQL) com 100 mL/h. A partir dos resultados obtidos pode-se constatar que para os mesmos parâmetros de usinagem a técnica do MQL utilizou uma quantidade muito menor de fluido e garantiu bons resultados de desgaste diametral do rebolo. No entanto, a qualidade da peça foi bem pior para o método do MQL em relação a técnica de refrigeração convencional. Estes resultados mostraram que se utilizando formas alternativas de lubrificação para reduzir o uso do fluido de corte, são possíveis dependendo de quais fatores são mais importantes para o processo que se deseja. Nesse sentido, se o método do MQL fosse adotado pelas empresas dependentes da retificação, certamente iria trazer, de um lado, benefícios quanto a problemas de descarte e reciclagem de fluido de corte, mas por outro lado, levaria a uma menor qualidade superficial das peças.
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Over the years, grinding has been considered one of the most important manufacturing processes. Grinding is a high precision process, and the loss of a single workpiece in this stage of the production is unacceptable, fir the value added to the material is very high due to many processes it has already undergone prior to grinding. This study aims to contribute toward the development of an experimental methodology whereby the pressure and speed of the air layer produced by the high rotation of the grinding wheel is evaluated with and without baffles, i.e., in an optimized grinding operation and in a traditional one. Tests were also carried out with steel samples to check the difference in grinding wheel wear with and without the use of baffles.
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Produced water has lately aroused interest due to their high degree of salinity, suspended oil particles, chemicals added in various manufacturing processes, heavy metals and radioactivity sometimes. Along with oil and due to its high volume production, water production is one of the pollutants of most concern in the process of oil extraction. PAHs due to their ubiquity and their characteristics carcinogenic or mutagenic and teratogenic even have attracted the attention of every scientific society. Formed from the incomplete combustion of organic matter may be natural or anthropogenic. Some materials have been researched with the goal of cleaning up environmental matrices that may be contaminated by hydrocarbons. Among these materials researched various clays have been employed, of which highlights the vermiculite. The family of phyllosilicates, vermiculite for its potential and its high hydrophobic surface area has been a tool widely used in the decontamination of water in processes of oil spills. However, when it loses its capacity expanded hydrophobic having the necessity of using a hidrofobizante to make it organophilic. Among the numerous hidrofobizantes researched and used the linseed oil was the pioneer. In this study sought to evaluate the capacity of removal of PAHs using the vermiculite hydrofobized with linseed oil and wax also, for it was made use of the 24 full factorial design as the main tool for the experiments. We also evaluated the clay grain size (-20 +48 and -48 +80 #), the percentage of hidrofobizante applied (5 and 10%) and salinity of the water produced synthesized in our laboratory (35,000 and 55,000 ppm). The molecular fluorescence spectroscopy due to its sensitivity and speed was used to verify the adsorption capacity of clay, as well as gas chromatography served as an auxiliary technique to identify and quantify the PAHs in solution. In order to characterize the vermiculite was made use of X-ray fluorescence and X-ray diffraction. The infrared and thermogravimetry were essential to note hydrophobization and the amount of coating of clay. According to the fluorescence analysis showed that the test 12 was the best result in about 98% adsorption of fluorescent compounds, however the high salinity, the smallest particle size, the highest percentage of hidrofobizante and the use of linseed oil showed greater efficiency in the removal capacity of these hydrocarbons, in accordance with the trend followed by the analysis of the major factors of the factorial design. To verify the adsorption capacity of clay using a fixed volume of water produced synthetically, used as the test base 12, at their respective levels and factors. Thus, it was observed that after adding about 1 ½ liters of water solution produced synthetically, about 300 times its volume in mass, the vermiculite was able to adsorb 80% of fluorescent species present in solution
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Digital factory is a concept that offers a collaborative approach to enhance product and production engineering processes through simulation. Products, processes and resources are modeled to be used to develop and test the product conception and manufacturing processes, before their use in the real factory. The purpose of this paper is to present the steps to identify the Critical Success Factors (CSF) priorities in a digital factory project implementation in a Brazilian company and how the Delphi and AHP Methods are aiding to identify these CSF priorities. Copyright © 2008 SAE International.
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For many years, composting has been used as a result of the recycling of organic matter. There is significative animal carcasses accumulation from teaching and researching activities of the university veterinary hospital. Every year, Unesp University needs to dispose correctly about 180 tones of this waste and the composting seemed to be the most sustainable alternative. Piles of animal carcasses were prepared using peanut hulls and tree pruning as bulking agent and water to the first phase of this process. The extracts pH values no impediments for offering germination and indicated a good addition to the soil management. The germination index showed no impediment to the seeds germination on any type of compost and the extracts concentrations not influenced this biological process. No parameters studied assigns risks of contamination of carcasses for the compost development in Unesp according to the proposed design. © 2013 Taylor & Francis Group.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Pós-graduação em Engenharia Mecânica - FEG
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Pós-graduação em Engenharia Mecânica - FEG