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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.
81

The evaluation of the repeatability and performance of the cast iron multifacet drill

Chou, Kou-Ching. January 1984 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1984. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 126-128).
82

Comparitive [sic] assessment of bit geometry and cutting parameters

Bhuvanapalli, Shiv K. January 2000 (has links)
Thesis (M.S.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains vi, 81 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 71-75).
83

Investigation of the effect of waterjet created slots in improving the performance of tricone drill bits in hard rock /

Pederick, Stuart. January 2005 (has links) (PDF)
Thesis (M.Eng.Sc.) - University of Queensland, 2005. / Includes bibliography.
84

Comparison of three drilling technologies to characterize the vadose zone, Hanford Site

Holm, Rochelle Hales, January 2007 (has links) (PDF)
Thesis (M.S. in environmental science)--Washington State University, August 2007. / Includes bibliographical references (p. 19).
85

Characterization of drillability of sandwich structure of carbon fiber reinforced epoxy composite over titanium alloy

Khasawneh, Firas Abdallah. January 2006 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on September 13, 2007). Vita. Includes bibliographical references.
86

Aspectos da furação do titânio 6Al4V com broca de aço rápido sinterizado e broca de metal duro / Drilling aspects from titanium 6Al4V with sintered high speed steel drill and carbide drill

Allegrini, Alex [UNESP] 14 July 2014 (has links) (PDF)
Made available in DSpace on 2015-03-03T11:52:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-07-14Bitstream added on 2015-03-03T12:07:08Z : No. of bitstreams: 1 000807370.pdf: 2293849 bytes, checksum: d68b7cab07938392e6c6fbc74359add9 (MD5) / As exigências e a competitividade atual levam, cada vez mais, à busca por soluções mais baratas e eficazes, para qualquer segmento de mercado. Com isso, o ramo aeronáutico tem procurado por ferramentas que possibilitem o mais alto rendimento possível aliado à redução de custos. Este trabalho de furação em placas de titânio 6Al4V tem origem em função da comunalidade de uso deste material nas indústrias, por manter alta resistência mecânica e a altas temperaturas. As ferramentas escolhidas foram brocas de metal duro e brocas de aço rápido sinterizado objetivando um estudo comparativo entre estas, nas mais variadas condições de corte, desde a refrigeração em abundância com utilização de óleo solúvel, passando pela usinagem à seco e finalizando com o sistema da Mínima Quantidade de Lubrificação (MQL) com óleo de corte puro. Os parâmetros de corte adotados foram conforme literatura técnica, para brocas de metal duro, utilizou-se velocidade de corte de 28 m/min, avanço total de 72 m/min e rotação de 2123 RPM e para as brocas de aço rápido sinterizado, velocidade de corte de 11 m/min, avanço total de 29 mm/min e rotação de 876 RPM. Anterior ao inicio dos testes, foi aplicado a ferramenta de Análise do Modo e Efeito de Falha a fim de identificar e prevenir possíveis discrepâncias na execução do processo de furação. A usinagem ocorreu em passes de 8mm de profundidade com interrupção a cada 200mm a 250mm para recolhimento de amostra de cavaco e avaliação parcial dos diversos possíveis desgastes nas ferramentas. Os parâmetros iniciais de finalização de cada broca foram estabelecidos com desgaste de 0,1mm ou tolerância de furos finais acima de H12. Os testes foram repetidos para ambas as brocas sempre em condições idênticas a fim de permitir uma comparação de resultados entre as ferramentas, geração ... (Resumo completo, clicar acesso eletrônico abaixo) / The current requirements and the competitiveness lead, increasingly, to the search for cheaper and more effective solutions, to any segment of the market.Thus the aeronautics the aviation industry has been searching for tools that allow the highest possible income combined with the cost reduction.. This work of drilling in 6Al4V titanium plates originates due to the commonality of use of this material in industries, for maintaining high mechanical strength and high temperatures. The tools chosen were carbide drills and drills of sintered high speed steel aiming at a comparative study between these, in the most varied cutting conditions, since refrigeration in abundance with use of oil soluble, through dry machining and finishing with the system of Minimal Quantity of Lubrication with neat cutting oil. The cutting parameters were adopted as technical literature, for carbide drills, used cutting speed of 28 m/min, total advance of 72 m/min and 2123 RPM rotation and sintered high speed steel drills, cutting speed of 11 m/min, total advance of 29 mm/min and 876 RPM rotation. Prior to the start of the tests, was applied to the analysis tool mode and effect of failure in order to identify and prevent possible discrepancies in the execution of the drilling process. The machining occurred in 8 mm deep steps with interruption every 200 mm to 250 mm for chip sample and partial evaluation of the various possible wear on tools. The initial parameters of completion of each drill were set with 0,1mm wear or tolerance of final holes above H12. The tests were repeated for both drills always in identical terms in order to allow a comparison of results between the tools, chip generation and final diameter. The diameters were measured with standard pins every 20 holes where, even after intense damage, there was no pre-established dimensional limits variation i.e. ... (Complete Abstract click electronic access below)
87

Aspectos da furação do titânio 6Al4V com broca de aço rápido sinterizado e broca de metal duro /

Allegrini, Alex. January 2014 (has links)
Orientador: Marcos Valério Ribeiro / Banca: José Vitor Candido de Souza / Banca: Alessandro Roger Rodrigues / Resumo: As exigências e a competitividade atual levam, cada vez mais, à busca por soluções mais baratas e eficazes, para qualquer segmento de mercado. Com isso, o ramo aeronáutico tem procurado por ferramentas que possibilitem o mais alto rendimento possível aliado à redução de custos. Este trabalho de furação em placas de titânio 6Al4V tem origem em função da comunalidade de uso deste material nas indústrias, por manter alta resistência mecânica e a altas temperaturas. As ferramentas escolhidas foram brocas de metal duro e brocas de aço rápido sinterizado objetivando um estudo comparativo entre estas, nas mais variadas condições de corte, desde a refrigeração em abundância com utilização de óleo solúvel, passando pela usinagem à seco e finalizando com o sistema da Mínima Quantidade de Lubrificação (MQL) com óleo de corte puro. Os parâmetros de corte adotados foram conforme literatura técnica, para brocas de metal duro, utilizou-se velocidade de corte de 28 m/min, avanço total de 72 m/min e rotação de 2123 RPM e para as brocas de aço rápido sinterizado, velocidade de corte de 11 m/min, avanço total de 29 mm/min e rotação de 876 RPM. Anterior ao inicio dos testes, foi aplicado a ferramenta de Análise do Modo e Efeito de Falha a fim de identificar e prevenir possíveis discrepâncias na execução do processo de furação. A usinagem ocorreu em passes de 8mm de profundidade com interrupção a cada 200mm a 250mm para recolhimento de amostra de cavaco e avaliação parcial dos diversos possíveis desgastes nas ferramentas. Os parâmetros iniciais de finalização de cada broca foram estabelecidos com desgaste de 0,1mm ou tolerância de furos finais acima de H12. Os testes foram repetidos para ambas as brocas sempre em condições idênticas a fim de permitir uma comparação de resultados entre as ferramentas, geração ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The current requirements and the competitiveness lead, increasingly, to the search for cheaper and more effective solutions, to any segment of the market.Thus the aeronautics the aviation industry has been searching for tools that allow the highest possible income combined with the cost reduction.. This work of drilling in 6Al4V titanium plates originates due to the commonality of use of this material in industries, for maintaining high mechanical strength and high temperatures. The tools chosen were carbide drills and drills of sintered high speed steel aiming at a comparative study between these, in the most varied cutting conditions, since refrigeration in abundance with use of oil soluble, through dry machining and finishing with the system of Minimal Quantity of Lubrication with neat cutting oil. The cutting parameters were adopted as technical literature, for carbide drills, used cutting speed of 28 m/min, total advance of 72 m/min and 2123 RPM rotation and sintered high speed steel drills, cutting speed of 11 m/min, total advance of 29 mm/min and 876 RPM rotation. Prior to the start of the tests, was applied to the analysis tool mode and effect of failure in order to identify and prevent possible discrepancies in the execution of the drilling process. The machining occurred in 8 mm deep steps with interruption every 200 mm to 250 mm for chip sample and partial evaluation of the various possible wear on tools. The initial parameters of completion of each drill were set with 0,1mm wear or tolerance of final holes above H12. The tests were repeated for both drills always in identical terms in order to allow a comparison of results between the tools, chip generation and final diameter. The diameters were measured with standard pins every 20 holes where, even after intense damage, there was no pre-established dimensional limits variation i.e. ... (Complete Abstract click electronic access below) / Mestre
88

Analise radiografica da região de furca, apos a confecção e contaminação de trepanações experimentais em dentes de cães seladas com diferentes materiais

Rodrigues, Ronaldo Rogerio 13 December 2000 (has links)
Orientador: Fabricio Batista Teixeira / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-07-27T10:31:53Z (GMT). No. of bitstreams: 1 Rodrigues_RonaldoRogerio_M.pdf: 2173324 bytes, checksum: 4537dbe5cef51b274531cf00699f4749 (MD5) Previous issue date: 2000 / Resumo: O objetivo deste trabalho foi analisar radiograficamente a perda óssea na região de furca, em dentes de cães, intencionalmente perfurados e contaminados pela exposição ao meio oral, frente ao emprego de vários materiais seladores da cavidade de acesso coronário. Foram utilizados 6 cães adultos, pesando entre 9 e 15Kg, fêmeas e de raça indefinida. Perfurações foram produzidas na região de furca dos 2°, 3° e 4° pré-molares inferiores direitos e esquerdos, permanecendo expostas à cavidade oral por um período de 30 dias. Após este intervalo de tempo, tendo constatado a formação das lesões de furca através de radiografias periapicais, os dentes foram limpos e tratados de acordo com a divisão dos grupos experimentais. As perfurações dos 2°, 3° e 4° pré-molares foram preenchidas com sulfato de cálcio hemidratado e seladas com guta-percha, IRM e resina Z-100, respectivamente, sendo descontaminadas com c1orexidina gel a 2% somente os dentes do lado direito. Radiografias padronizadas foram realizadas no início do experimento, 3 O dias após a exposição das perfurações à cavidade oral e 180 dias após o emprego dos materiais seladores. As imagens foram transportadas para o computador e mensuradas as áreas de perda óssea utilizando o programa "ImageLab". Os resultados foram analisados estatisticamente e as imagens demonstraram menor perda de estrutura óssea quando as perfurações foram seladas com resina Z-100, ao serem comparadas com IRM e guta-percha, demonstrando menor perda óssea com a utilização da c1orexidina gel a 2% para a descontaminação / Abstract: The objective of this work was to analysis radiographically the bony loss in the furcation region, in dog's teeth, intentionally perforated and contaminated with oral fluids, about the employment of several sealer materiaIs. It was utilized 6 adult dogs, weighing from 9 to 15 kilograms, females and the indefmite race. Perforations were produced in the furcation's region from the 2°, 3°, and 4° inferior right and left premolars, and they stayed exposed to the oral cavity for a period of 30 days. Afterwards this interview of time, was found the formation of furcation' s lesions by periapical radiography, the teeth were cleaned and treated in accord to the experimental groups division. The perforation of the 2°, 3°, and 4° premolars were fulfilled with hemihydrated calcium sulfate and sealed with gutta-percha, IRM and Z-100 resin, respectively, and just the right side teeth's perforation were decontaminated with 2% gel chlorhexidine. Padronized radiographic were made in the beginning of the experiment, 30 days after the exposition of the perforations to the oral cavity and 180 days after the employment of the sealer materiaIs. The images were transported to the computer and the areas of the bony loss were measured utilizing the "ImageLab" programo The results were analyzed statically andthe images demonstrated minor loss of bony structure when the perforation were sealed with Z-100 resin, in comparation to IRM and gutta-percha, demonstrating minor bony loss with the utilization of 2% gel chlorhexidine for the decontamination / Mestrado / Endodontia / Mestre em Clínica Odontológica
89

Effects of Minimum Quantity Lubrication in Drilling 1018 Steel.

Shaikh, Vasim 12 1900 (has links)
A common goal for industrial manufacturers is to create a safer working environment and reduce production costs. One common method to achieve this goal is to drastically reduce cutting fluid use in machining. Recent advances in machining technologies have made it possible to perform machining with minimum-quantity lubrication (MQL). Drilling takes a key position in the realization of MQL machining. In this study the effects of using MQL in drilling AISI 1018 steel with HSS tools using a vegetable based lubricant were investigated. A full factorial experiment was conducted and regression models were generated for both surface finish and hole size. Lower surface roughness and higher tool life were observed in the lowest speed and feed rate combination.
90

The effects of variables and variable interactions on tin coated drill performance

Childs, James Joseph January 1983 (has links)
Today, drilling can be considered the most common of all metal cutting operations. Drilling can be accomplished on nearly all machines that can produce a relative rotation of the spindle, and/or the workpiece. These machines can include drill presses, lathes, milling machines and machining centers. Of the more than 1.70 million machine tools in the United States, that are located in plants employing more than twenty workers, more than half of these machines can, and probably are performing drilling functions. Drilling has been studied in numerous investigations with the objective of increasing drill performance. Severely lacking in this research has been the use of statistically designed experiments. Traditional experimental techniques in tooling have been conducted under a one variable at a time methodology. The twist drill, however, is one of the most complex metal cutting tools in existence today. Changing one variable at a time can lead to unwanted changes in other variables. With today's statistical techniques and computers, variables and variable interactions should be able to be adjusted and controlled. Because drilling is one of the leading metal cutting operations, an ever so slight increase in the level of drill performance could yield important benefits to manufacturing. Investigation into drill geometry and variable interaction may also lead to significant increases in drill performance. A quantitative analysis was performed to determine the effect of different independent variables on tool life for Titanium Nitride Coated tools. This was accomplished in two stages. In Stage 1, the variables lip height, helix angle, and margin width were tested one at a time for their effect on tool life. In Stage 2, the variable lip height from Stage 1 and the independent variables, speed and feed, were tested for their effect on tool life in a three variable, two level factorial treatment design. Secondary measurements were also taken in Stage 2 on acceleration, torque and face wear. Stage 1 showed that tighter tolerances on lip height could improve tool life. The 39 degree helix angle was more of a detriment than an aid, to increase tool life. The lowest level of margin width had lower tool life than either of the other two levels. In stage 2 feed and lip height had a significant effect on tool life at the 90% confidence level. Speed did not have an effect on tool life. No variable in Stage 2 had an significant effect on acceleration at either the 95% or 90% confidence level. At the low level of the feed, acceleration readings seemed applicable in determining pending tool failure. The largest values of crater width on the face were associated with the low values of feed. No true distinction can be made with torque, between any of the combinations of levels tested. This research has attempted to further quantify some of the variables and variable interactions associated with drilling for Titanium Nitride Coated tools. / M.S.

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