Estudo das propriedades mecânicas do aço SAE 1312 modificado ao nióbio

The study of mechanical properties of high-alloy special steels is of great interest of the steel industry due to the great demand by companies that manufacture automotive components of high criticality, and also because of its high commercial value. However, the development of this type of alloy metals demand highly technical knowledge. Among these extremely important kinds of steel, the subject which is the interest of this study is the special steel modified by niobium. The manganese and niobium are the main alloying elements in the composition of these steels, both of them increase the stability of the austenite region, however, manganese increases the hardenability and tensile yield strength, and niobium increases the mechanical strength and promotes refining the grain. The mechanical characterization of steel SAE 1312 modified the niobium was made in order to gain a better understanding of the influence on the mechanical properties caused by aging at different temperatures and for different reductions in the drawing of gauge material. This characterization was made by means of tensile test and hardness. This material showed an increase in yield strength and hardness when gauge with large reductions during the wiredrawing, but when subjected to aging temperatures higher than 300 ° C had a slight loss of these properties

Produção de carvão vegetal a partir da madeira de Eucalyptus saligna clone SI70 com tres anos e meio de idade

Charcoal is obtained from carbonization, much used in the steel industry for ore reduction, using as raw material the Eucalyptus. The present study aims to verify whether the main Eucalyptus saligna genetically modified produce quality charcoal with only 3.5 years old. The study was done with material collected from three trees, divided into five discs removed at 0, 25 , 50 , 75 and 100 % of the commercial height of the tree. The procedures adopted were based on standards published by ABNT. The results were satisfactory for the parameters: basic wood density with an average of 0.39 ± 0.0082 g / cm ³; volatile materials from coal with an average of 19.35 ± 3.27 %, fixed carbon content of the coal with an average of 75.62 ± 3.40 % and gross calorific value of coal with an average of 4694.43 cal / g, and unsatisfactory results for ash content averaging 5.03 ± 0.23 when compared to the values found in the literature. It was concluded that the studied wood is able to produce charcoal, but the factors of production should be better observed, such as heating time which exerted direct influence on the determination of ash content

O Serviço Social e a avaliação de impacto na gestão de programas e projetos empresariais

Pós-graduação em Serviço Social - FCHS

A concentração do mercado siderúrgico: uma análise dos indicadores CR4 e HHI no períiodo 1990-2010

The paper analyses the concentration degree in the global steel industry in the 1990-2010 period. Using the Herfindahl-Hirschman (HHI) index, the paper has concluded that concentration in the world steel industry increased, mainly because the increase of acquisitions and fusions among firms.

A contribution to the identification of charcoal origin in brazil i - anatomical characterization of corymbia and eucalyptus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desenvolvimento de metodologia para implementação de eficiência energética em sistemas auxiliares de uma planta industrial siderúrgica semi-integrada

Pós-graduação em Engenharia Mecânica - FEG

Implementação do OEE nas máquinas de laminação a frio

Through a description of the productivity problems experienced by some enterprises, to optimize their respective production lines, results of poor performance or low quality, the following work aims to explain and demonstrate the practical application of the theory of overall equipment effectiveness (OEE) on cold lamination machines in a steel industry . The project, to ensure your goal, is based on structuring a complete planning to increase levels of performance, availability and quality relating to rolling. On completion of the work, will be presented forecasts of future goals for the OEE, to search for continuous improvement and global standards of efficiency, taking into account, the sector the company operates, the history of the laminators, and financial aspects

Utilização de trocadores de calor de placas em espiral em processos da indústria siderúrgica

Stricter environmental policies are shown necessary to ensure an effective pollutant emission control. It is expected for the present year of 2015, that Brazil will assume, at the 21th United Nation's Climate Change Conference (COP21), implementation of commitment to a low carbon economy. This positioning affects the industrial environment, so that is deemed necessary to search for new technologies, less aggressive to the environment, so the adequacies to the new emission policies do not cause a negative effect on production. Almost all of the processes performed in the steel industry demand burning fuel and, therefore, flue gases are sent to the atmosphere. In this present work is discussed the utilization of heat exchangers so, by recovering part of the available heat from the flue gases of certain industrial process, the combustion air is preheated. The combustion air preheat results in less energy requirement, i.e., less need of fuel consumption and, in addition, minor amount of pollutants to be emitted. Due to better fitting to the process, it is studied the utilization of spiral plate heat exchangers. The heat exchanger dimensioning is made by an iterative method implemented in the software Microsoft Excel. Subsequently are analyzed the gains in terms of process's thermal efficiency improvement and the percentage of fuel saving. The latter implies in reduction of the same percentage of greenhouse gases emission

Implementação do OEE nas máquinas de laminação a frio

Through a description of the productivity problems experienced by some enterprises, to optimize their respective production lines, results of poor performance or low quality, the following work aims to explain and demonstrate the practical application of the theory of overall equipment effectiveness (OEE) on cold lamination machines in a steel industry . The project, to ensure your goal, is based on structuring a complete planning to increase levels of performance, availability and quality relating to rolling. On completion of the work, will be presented forecasts of future goals for the OEE, to search for continuous improvement and global standards of efficiency, taking into account, the sector the company operates, the history of the laminators, and financial aspects

Utilização de trocadores de calor de placas em espiral em processos da indústria siderúrgica

Stricter environmental policies are shown necessary to ensure an effective pollutant emission control. It is expected for the present year of 2015, that Brazil will assume, at the 21th United Nation's Climate Change Conference (COP21), implementation of commitment to a low carbon economy. This positioning affects the industrial environment, so that is deemed necessary to search for new technologies, less aggressive to the environment, so the adequacies to the new emission policies do not cause a negative effect on production. Almost all of the processes performed in the steel industry demand burning fuel and, therefore, flue gases are sent to the atmosphere. In this present work is discussed the utilization of heat exchangers so, by recovering part of the available heat from the flue gases of certain industrial process, the combustion air is preheated. The combustion air preheat results in less energy requirement, i.e., less need of fuel consumption and, in addition, minor amount of pollutants to be emitted. Due to better fitting to the process, it is studied the utilization of spiral plate heat exchangers. The heat exchanger dimensioning is made by an iterative method implemented in the software Microsoft Excel. Subsequently are analyzed the gains in terms of process's thermal efficiency improvement and the percentage of fuel saving. The latter implies in reduction of the same percentage of greenhouse gases emission

Análise do processo de preparação da produção no desenvolvimento de novos produtos por meio de um estudo de caso em uma empresa do setor siderúrgico

A demanda por novos produtos tem aumentado em algumas empresas do setor siderúrgico, indicando uma crescente preocupação com o desempenho do processo de desenvolvimento de produtos (PDP), que depende de vários elementos conceituais importantes apontados na literatura. Em uma empresa siderúrgica, um fator relevante é o projeto do processo de produção, devido à característica de ser um processo de fabricação contínuo e por, geralmente, envolver investimentos significativos na fase de preparação da produção. Nesse contexto, o presente trabalho busca realizar uma análise desta fase em uma empresa siderúrgica. Pretende-se, por meio da abordagem metodológica de estudo de caso, identificar práticas organizacionais, focando nos aspectos operacionais e suas interfaces, envolvendo as áreas funcionais de marketing, engenharia do produto e manufatura. Também é tratada no trabalho a integração dos times multidisciplinares, a tomada de decisão e os critérios para avaliação dos resultados do PDP. O trabalho conclui que a empresa analisada utiliza-se de práticas que estruturam a preparação da produção e que a integração interfuncional das áreas é o que se destaca para o sucesso do PDP.

The Extraction of Manganese from Manganese Flue Dust.

It is estimated that 90 to 95% of the world’s consumption of manganese is used in the steel industry in the form of either ferromanganese or spiegeleisen. The remainder is used in the form of either salts or oxides, chloride, dioxide and monoxide.

Relationships of Manganese Minerals in the Butte District

The use of manganese in the steel industry as a deoxidizing and desulfidizing agent makes it a necessity in modern industry, while the various alloy steels using manganese for the quality of toughness are also indispensable. Manganese is also used in the manufacture of such various articles as battery cells, paints and glass.

A Preliminary Investigation of the Hydrometallurgy of Philipsburg Manganese

In the past the steel industry of the United States has depended almost wholly on imports for its supplies of manganese. Although it is well known that there are enormous deposits of low grade manganese ore in the United States the production of substantial amounts of ferro-grade mater­ial from domestic sources presents a field for con­structive and practical research.

A Mineral Dressing Study of the Benefication of Philipsburg Manganese Carbonate Ore

The beneficiation of rhodochrosite ore to the extent that it is suitable for nodulizing and subsequent use in the steel industry is intriguing. Such ores from certain mines is relatively easy to beneficiate, but the rhodo-chrosite ore from several deposits of the Philipsburg district has never been successfully up-graded by any of the several known beneficiating methods.