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Cloverdale Furnace: a century of iron manufacture in Botetourt County Virginia, 1789-1889Turner, Jeffrey C. 27 February 2007 (has links)
In an effort to answer broad, contextual questions concerning early 19th Century American industrial history, it is often necessary to supplement generally accepted premises with observations of particular instances. This study of Cloverdale Furnace constitutes such an observation. Particular attention has been paid to details of person, place and practice as gained from Botetourt County Records and the correspondence between such furnace owners as the Breckenridge, Tayloe and Anderson families.
The ultimate fate of charcoal-fired iron furnaces is so well known as to require little or no comment. That Cloverdale continued into, and beyond the period of the United States Civil War, depended upon a variety of causes. It probably would have ceased operation in 1859 - 1860, but for crisis of the Union. Other causes for Cloverdale's success and perseverance included: availability of capital, labor, raw materials and managerial talent. Not all of these were distinctive, but some were enough so to deserve special note.
The study is chronologic. It begins with the establishment of the furnace in 1789, and ends with the final mining activity of 1889. During this period, there were two separate furnaces located within eight miles of each other. Each was named Cloverdale and each produced high grade charcoal-smelted "gun metal." The operation of Cloverdale Number 1 was based on craft techniques and linked to a local market. The owners were largely absentee investors who utilized their existing slave force for labor. Cloverdale Number 2 was based on a regional market and incorporated a more advanced technology in furnace construction. Under the ownership of John T. Anderson, and later, Joseph R. Anderson, Cloverdale Number 2 achieved a reputation second to none in the eastern part of the United states for producing quality "gun metal" and supplied the Tredegar Works in Richmond with the same. Unfortunately, the reputation was not enough to protect the firm from collapse due to depleted timber reserves and natural resources. / Master of Arts
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" La Fonte ardennaise " et ses marchés : Histoire d'une PME familiale dans un secteur en déclin (1926-1999) / " La fonte ardennaise " and its markets : A history of a family-run SME whithing a declining sector (1926-1999)Prati, Bruno 01 February 2013 (has links)
L’histoire de La Fonte Ardennaise est celle de la transformation d’une petite fonderie artisanale fondée dans les années 1920 en une entreprise de taille intermédiaire et d’envergure européenne au début du XXIe siècle. Sa création par un ouvrier mouleur est expliquée par l’étude d’un secteur industriel mal connu, celui de la fonderie de seconde fusion, et de la spécificité de sa localisation dans le département des Ardennes.La monographie de La Fonte Ardennaise est aussi celle d’une famille qui met en perspective la trajectoire de deux générations d’entrepreneurs et aide à expliquer les singularités de la croissance, du financement et du contrôle d’une PME familiale. Afin de mieux comprendre ce qui peut être considéré comme une success story, l’effort d’adaptation de l’entreprise à son environnement est mis en relation avec les mouvements du marché et le comportement de la branche.Étrangers aux schémas mentaux des fondeurs établis, Émile, puis Gérard Grosdidier développent une approche commerciale originale qui différencie l’entreprise de la concurrence et permet une logique de croissance externe et interne, ce qui, en creux, propose des hypothèses explicatives à l’échec du modèle industriel local. Mais la cristallisation de l’organisation sur un leader charismatique rend difficile tant l’intégration de nouveaux dirigeants que la transmission du pouvoir à la troisième génération familiale / The history of La Fonte Ardennaise is about a small, traditional foundry founded in the 1920s that grew into a mid-sized business of European scope in the early 21st century. The company was created by a casting worker, and this can be explained by studying a little-known industrial sector, namely that of second smelting, and by the specific features of its location within the département of Ardennes.A monograph about La Fonte Ardennaise also tells the story of a family, highlighting the path taken by two generations of entrepreneurs, and helps to understand the idiosyncrasies pertaining to the growth, funding and management of a family-run SME. In order to better appreciate what could be viewed as a success story, the efforts made by the company to adapt to its environment are juxtaposed with what was happening in the market and with the way in which the branch progressed.Unconcerned with the mental schemes favoured by established foundries, Émile Grosdidier, and Gerard Grosdidier after him, succeeded in developing an original commercial approach that differentiated the company from the competition, fostering external and internal growth, thereby raising implied assumptions that explain the failure of the local industrial model. Yet having an organisation that is entirely focused on a charismatic leader makes it difficult to bring in new management, as well as transferring power to the family’s third generation
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A programação de produção em fundições de pequeno porte: modelagem matemática e métodos de solução / The production planning is small-driven foundries: mathematical modeling and solution methodsFink, Claudia 24 April 2007 (has links)
Este trabalho trata de um problema de programação da produção em fundições de pequeno porte, que consiste em programar as ligas que devem ser produzidas em cada período do planejamento e como tais ligas devem ser usadas para a produção de itens sob encomenda, de modo que atrasos e custos operacionais sejam minimizados. Devido à certa incerteza nos dados do problema, a estratégia de horizonte rolante foi empregada. Este problema é representado por um modelo matemático de programação linear inteira mista. Neste trabalho foi desenvolvida uma heurística do tipo residual para obter uma boa solução inteira factível do problema, partindo da solução contínua encontrada pelos métodos relaxe-e-fixe e busca local / This work addresses a planning production problem that arises in small market-driven foundries, which consists of programming a number of alloys that have to be produced in each period of the planning horizon and how these alloys should be used to producing ordered items, in such way that delays and operational costs are minimized. Due to uncertainties in the problem data, the strategy of rolling horizon was used. This problem is modeled as a mixed integer linear programe. In this work we developed a residual typed heuristic in order to obtain a good feasible integer solution of the problem, which are built from the continuous solution found by relax-and-fix and local search methods. Keywords: Lot-sizing problems, mixed integer linear programming, production planning in foundries
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Avaliação dos indicadores biológicos de exposição aos metais em trabalhadores de fundições / Evaluation of biological indicators of exposure to metals in foundry workersSantos, Claudia Regina dos 07 December 2004 (has links)
A produção de metais sanitários é um setor em constante fase de crescimento no país. O processo industrial envolve etapas como a evaporação, condensação e oxidação dos metais no ar que levam a formação de fumos metálicos em vários tipos de indústria, inclusive em fundições. A exposição do trabalhador ao ambiente contaminado pode levar ao aparecimento de alterações bioquímicas e, em algumas circunstâncias, de doenças profissionais. No setor de metais sanitários, são utilizadas ligas metálicas de latão, onde predomina o zinco e o cobre, sendo o chumbo, cádmio, manganês e níquel, metais que aparecem sob a forma de impurezas. Desses metais, apenas o chumbo sanguíneo (Pb-S) e o cádmio urinário (Cd-U) são regulamentados no Brasil, de acordo com a NR-7 do Ministério do Trabalho, como indicadores biológicos de exposição. No presente estudo, foram otimizados e validados métodos para a determinação de Pb-S, Cd-U, Mn-U e Ni-U por espectrometria de absorção atômica acoplado a forno de grafite. Posteriormente foram avaliados 273 indivíduos do sexo masculino (178 do grupo exposto e 95 do grupo controle) que trabalhavam em 8 fundições de metais sanitários de Loanda-PR. Os níveis de Pb-S apresentaram-se elevados, considerando o limite internacional. Os metais avaliados na urina Cd-U, Mn-U e Ni-U apresentaram concentrações relativamente baixas, sendo considerado o chumbo como o principal problema, relacionado aos fumos metálicos. Foram propostas medidas corretivas nos ambientes de trabalho e os níveis dos quatro metais em questão foram reavaliados em dois períodos diferentes (antes e após as modificações), apresentando no segundo momento reduções estatisticamente significativas. As médias observadas nos dois períodos foram de 42,74µg/dL e 26,54µg/dL para o Pb-S; 0,269 e 0,015µg/g de creatinina para o Cd-U; 1,94 e 0,39µg/g de creatinina para o Mn-U e 1,82 e 0,68µg/g de creatinina para o Ni-U, com níveis de significância (p) < 0,05, evidenciando assim a importância da adequação do ambiente de trabalho na garantia de exposições seguras para o trabalhador. / The sanitary metal production is a sector in constant development in Brazil. This industrial process involves stages such as evaporation, condensation and oxidation of metals, therefore allowing the formation of metallic fumes in some types of industry, and also in foundries. The contaminated environment can induce, in the workers, biochemical alterations and, in some circumstances, occupational diseases. In the sanitary metal sector, alloys are used in which predominate the metals zinc and copper, being lead, cadmium, manganese and nickel, metals that can be found in the form of impurities. According to Brazilian legislation\'s (Ministry of Work) only lead in blood and cadmium in urine are regulated as biological monitoring of exposure. In the present study, methods based on graphite furnace atomic absorption spectrometry and zeeman background correction were validated for quantification of Pb-B, Cd-U, Mn-U and Ni-U, and 273 male individuais (178 exposed group and 95 non exposed - control group), working in 8 sanitary metal foundries, in Loanda, Paraná, a state located in the south of Brazil, were evaluated. The levels of Pb-B were higher than the international permissible limit. Relatively low concentrations were found for the other evaluated metals: Cd-U, Mn-U and Ni-U, thus lead can be considered, in this case, the main problem, associated with metallic fumes. Corrective measures in the work environment were proposed and implemented, thus the four metais were evaluated in two distinct situations (biological determinations were done before and after the modifications). The results of the second evaluation showed reductions those were statistically significant. The means obtained in the two determinations were 42,74µg/dL and 26,54µg/dL for Pb-B; 0,269 and 0,015µg/g creatinine for Cd-U; 1,94 and 0,39µg/g creatinine for Mn-U and 1,82 and 0,68µg/g creatinine for Ni-U, with leveis of significance (p) < 0,05, thus evidencing the importance of the adequacy of the work environment in the guarantee of safe exposures for the workers.
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Avaliação dos indicadores biológicos de exposição aos metais em trabalhadores de fundições / Evaluation of biological indicators of exposure to metals in foundry workersClaudia Regina dos Santos 07 December 2004 (has links)
A produção de metais sanitários é um setor em constante fase de crescimento no país. O processo industrial envolve etapas como a evaporação, condensação e oxidação dos metais no ar que levam a formação de fumos metálicos em vários tipos de indústria, inclusive em fundições. A exposição do trabalhador ao ambiente contaminado pode levar ao aparecimento de alterações bioquímicas e, em algumas circunstâncias, de doenças profissionais. No setor de metais sanitários, são utilizadas ligas metálicas de latão, onde predomina o zinco e o cobre, sendo o chumbo, cádmio, manganês e níquel, metais que aparecem sob a forma de impurezas. Desses metais, apenas o chumbo sanguíneo (Pb-S) e o cádmio urinário (Cd-U) são regulamentados no Brasil, de acordo com a NR-7 do Ministério do Trabalho, como indicadores biológicos de exposição. No presente estudo, foram otimizados e validados métodos para a determinação de Pb-S, Cd-U, Mn-U e Ni-U por espectrometria de absorção atômica acoplado a forno de grafite. Posteriormente foram avaliados 273 indivíduos do sexo masculino (178 do grupo exposto e 95 do grupo controle) que trabalhavam em 8 fundições de metais sanitários de Loanda-PR. Os níveis de Pb-S apresentaram-se elevados, considerando o limite internacional. Os metais avaliados na urina Cd-U, Mn-U e Ni-U apresentaram concentrações relativamente baixas, sendo considerado o chumbo como o principal problema, relacionado aos fumos metálicos. Foram propostas medidas corretivas nos ambientes de trabalho e os níveis dos quatro metais em questão foram reavaliados em dois períodos diferentes (antes e após as modificações), apresentando no segundo momento reduções estatisticamente significativas. As médias observadas nos dois períodos foram de 42,74µg/dL e 26,54µg/dL para o Pb-S; 0,269 e 0,015µg/g de creatinina para o Cd-U; 1,94 e 0,39µg/g de creatinina para o Mn-U e 1,82 e 0,68µg/g de creatinina para o Ni-U, com níveis de significância (p) < 0,05, evidenciando assim a importância da adequação do ambiente de trabalho na garantia de exposições seguras para o trabalhador. / The sanitary metal production is a sector in constant development in Brazil. This industrial process involves stages such as evaporation, condensation and oxidation of metals, therefore allowing the formation of metallic fumes in some types of industry, and also in foundries. The contaminated environment can induce, in the workers, biochemical alterations and, in some circumstances, occupational diseases. In the sanitary metal sector, alloys are used in which predominate the metals zinc and copper, being lead, cadmium, manganese and nickel, metals that can be found in the form of impurities. According to Brazilian legislation\'s (Ministry of Work) only lead in blood and cadmium in urine are regulated as biological monitoring of exposure. In the present study, methods based on graphite furnace atomic absorption spectrometry and zeeman background correction were validated for quantification of Pb-B, Cd-U, Mn-U and Ni-U, and 273 male individuais (178 exposed group and 95 non exposed - control group), working in 8 sanitary metal foundries, in Loanda, Paraná, a state located in the south of Brazil, were evaluated. The levels of Pb-B were higher than the international permissible limit. Relatively low concentrations were found for the other evaluated metals: Cd-U, Mn-U and Ni-U, thus lead can be considered, in this case, the main problem, associated with metallic fumes. Corrective measures in the work environment were proposed and implemented, thus the four metais were evaluated in two distinct situations (biological determinations were done before and after the modifications). The results of the second evaluation showed reductions those were statistically significant. The means obtained in the two determinations were 42,74µg/dL and 26,54µg/dL for Pb-B; 0,269 and 0,015µg/g creatinine for Cd-U; 1,94 and 0,39µg/g creatinine for Mn-U and 1,82 and 0,68µg/g creatinine for Ni-U, with leveis of significance (p) < 0,05, thus evidencing the importance of the adequacy of the work environment in the guarantee of safe exposures for the workers.
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Respirable crystalline silica dust exposure amongst foundary workers in Gauteng (South Africa) : a task-based risk assessmentKhoza, Norman Nkuzi January 2012 (has links)
Thesis (MPH. (Occupational and Environmental Health))-- University of Limpopo, 2012 / Background: The objective of this study was to quantify personal time-weighted average respirable dust and silica exposure of workers at foundries in Gauteng and to rank the occupations in foundries according to the risk of exposure to silica quartz.
Methods: A task-based risk assessment of 56 personal samples from two foundries was conducted. Personal exposure data was collected from workers’ breathing zones for the full working shift. All analyses of samples for silica dust were carried out in the CSIR Centre for Mining Innovation’s Laboratory, which has SANAS accreditation (ISO 17025) for both x-ray powder diffraction and particle size analysis methods.
Results: The personal time-weighted average mean and median respirable silica dust concentration was 0.184 mg/m³ and 0.167 mg/m³ respectively. The maximum exposure concentration was 0.835 mg/m³ and minimum exposure was 0.010 mg/m³.
The occupations within the foundries with the highest exposures were moulders, sand mixers, furnace operators and the lowest exposed occupations were grinders, closers, and casting operators. The majority of foundry workers (62%) in both foundries are exposed to respirable silica dust at above the South African occupational exposure level (OEL).
Conclusion and recommendations: Foundry workers are over-exposed to respirable silica dust and are potentially at high risk of contracting silicosis and other occupational diseases associated with respirable silica dust. It is recommended that a dust control programme be implemented and a baseline study be conducted.
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A programação de produção em fundições de pequeno porte: modelagem matemática e métodos de solução / The production planning is small-driven foundries: mathematical modeling and solution methodsClaudia Fink 24 April 2007 (has links)
Este trabalho trata de um problema de programação da produção em fundições de pequeno porte, que consiste em programar as ligas que devem ser produzidas em cada período do planejamento e como tais ligas devem ser usadas para a produção de itens sob encomenda, de modo que atrasos e custos operacionais sejam minimizados. Devido à certa incerteza nos dados do problema, a estratégia de horizonte rolante foi empregada. Este problema é representado por um modelo matemático de programação linear inteira mista. Neste trabalho foi desenvolvida uma heurística do tipo residual para obter uma boa solução inteira factível do problema, partindo da solução contínua encontrada pelos métodos relaxe-e-fixe e busca local / This work addresses a planning production problem that arises in small market-driven foundries, which consists of programming a number of alloys that have to be produced in each period of the planning horizon and how these alloys should be used to producing ordered items, in such way that delays and operational costs are minimized. Due to uncertainties in the problem data, the strategy of rolling horizon was used. This problem is modeled as a mixed integer linear programe. In this work we developed a residual typed heuristic in order to obtain a good feasible integer solution of the problem, which are built from the continuous solution found by relax-and-fix and local search methods. Keywords: Lot-sizing problems, mixed integer linear programming, production planning in foundries
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Perception and implementation of Zero Defect Manufacturing approach in foundriesSaliji, Mohamed January 2022 (has links)
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.
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Moderna alternativ för skänkvärmning inom gjuteribranschen / Modern alternatives for ladle preheating in foundriesNyberg, Erik, Ahlstrand, Linus January 2020 (has links)
Sveriges och världens industrier står inför stora omställningar gällande energianvändning och klimatavtryck. Johnson Metall AB jobbar ständigt med miljöarbete och har identifierat gasolanvändningen i produktionen som ett ställe där stora miljövinster går att göra. Examensarbetet avgränsas till att enbart titta på alternativa förvärmningstekniker till skänkar.Syftet med rapporten är att undersöka 3-5 alternativa förvärmningstekniker till den gasoluppvärmning som används i dagsläget. Det är viktigt att en alternativ lösning gör så att nuvarande produktkvalitet bibehålls samtidigt som en alternativ lösning bidrar till ett lägre klimatavtryck, det är även viktigt att priset på produkterna inte går upp allt för mycket.För att genomföra examensarbetet har metoderna litteratursökning, Double Diamond, nulägesanalys, komparation och kriterieviktsmetoden använts. För att skapa en bild över uppvärmningsförloppet görs en testmätning som jämförs med teoretiska samband.Utbudet av klimatavtrycksminskande teknik är relativt stor och fortsätter att växa, däremot råder det brist på incitament att byta teknik. Det krävs stora investeringar i ny teknik som är relativt obeprövad. Bränslen som skulle kunna nyttjas blir indirekt reserverade för andra teknikslag till följd av konkurrensen på bränslemarknaden. I dagens läge ligger risktagandet i övergången till ny klimatneutral teknik hos industrin.Det alternativ som har störst potential är en elektrisk lösning. Förändringar i anläggningen kommer inte innebära någon större inverkan i produktionen. Konsekvenserna av att byta förvärmningsteknik är att produkterna förmodligen kommer öka i pris, men att produkten också får ett lägre klimatavtryck. / Due to the consequences of global warming the industries of the world are facing new challenges. Johnson Metall AB is continuously working with ways to reduce their environmental footprint. Johnson Metall AB has identified use of liquid petroleum gas (LPG) as a source where great environmental gains can be made. The thesis limits itself to only look at LPG use in ladle preheating.The purpose of the thesis is to investigate 3-5 alternative ladle preheating technologies instead of the current LPG preheating of ladles. It is important that an alternative solution keeps the current quality of the products and contributes to lower emissions, it is also important that the price of the products doesn’t increase too much. In order to investigate available options the following methods have been used: literature study, double diamond, current situation analysis, comparison method, and the criterion weight method. In order to create a picture of the heating of ladles, an evaluation measure is performed and compared with theoretical concepts. Climate friendly alternatives are present on the market and are continuously improving, however the incentives to invest in new technologies are few. From the industries perspective the available options are expensive and relatively untested. Fuels that are viable options are taken from consideration due to hard competition with other markets. Moving to alternative fuels is a risky business with few guarantees for the foundry industries. The alternative with the biggest potential is an electric solution. Changes in the facility will not result in any major interference in production. The consequences of changing ladle preheating technology will probably be an increase in the price of the products, however the product will be more environmentally friendly.
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Foundry Facilities in Industrial Arts Programs in the State of TexasLange, Robert Douglas 05 1900 (has links)
The problem of this study was to determine how much foundry equipment exists in the high schools of Texas and to determine to what extent it is being utilized. The data for this study were provided by thirty-seven metalworking instructors of Texas high schools.
Of the Texas high schools offering metalworking as a part of the industrial arts curriculum, few appear to have adequate foundry facilities. In addition, a deficiency seems evident in the background and training in foundry of the metalworking instructors.
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