As operações de usinagem compreendem uma parcela significativa do universo da manufatura sendo que atualmente algumas tendências bem definidas, como a usinagem de peças já endurecidas, vêm ganhando espaço no campo da fabricação de moldes e matrizes, em especial, mas também na indústria automotiva e de construção de máquinas. O torneamento e o fresamento de materiais, nesta difícil condição de usinagem, já estão estabelecidos na indústria. Assim, a conversão do processo de produção atual de materiais em estado mole para endurecido só será possível com todas as operações de usinagem incluídas. Devido a isso, a demanda por furação e roscamento de peças endurecidas está em constante crescimento. Essas operações apresentam dificuldades muito maiores do que as de torneamento e fresamento, daí a importância de ferramentas especificamente projetadas para elas. Dessa forma, este trabalho teve como objetivo estudar o processo de desgaste sofrido pelas ferramentas durante a furação e roscamento de aços AISI D2 e AISI H13 com a utilização de diferentes velocidades de corte. As forças de corte e o torque também serão medidos durante o processo para avaliar seus comportamentos com o aumento da velocidade. Com os resultados obtidos verificou-se que na furação e roscamento de aços endurecidos de baixa usinabilidade, como no caso do aço AISI D2, o desgaste da ferramenta é muito acentuado, podendo tornar o processo inviável economicamente caso não sejam empregadas velocidades de corte extremamente reduzidas. De uma forma geral, a furação e o roscamento do AISI H13 pode ser viável, pois o número de furos/roscas obtidos dentro dos critérios especificados mostrou-se muito superior ao esperado. Os principais mecanismos de desgastes que atuaram nos machos de corte durante o processo de roscamento de ambos os aços (AISI D2 e AISI H13) foram abrasão nas superfícies de folga e adesão nas superfícies de saída de forma acentuada nos três primeiros filetes. / The cutting processes compose a huge part of the manufacturing universe and, nowadays, some well-defined trends, like cutting hardened materials, are increasing not only in die molding production but also in automotive and machine industries. The turning and milling processes of materials, in this difficult condition of cutting, are already applied in the mechanical industries. Therefore, the total conversion of the present production process of regular materials into hardened ones can only be reached when all the cutting processes are included. Because of that, the demands of drilling and tapping hardened materials have increased constantly. These operations require tools specifically designed for them, because they have proven themselves to be much more difficult than the turning and milling processes. In that way, this work aimed to study the wear process of drills and taps used to machining the AISI D2 and AISI H13 hardened steels with different cutting speeds. The cutting forces and the torque generated were also acquired during the cutting process to evaluate its behavior with the speed increase. After analyzing the results, a very aggressive tool wear was confirmed in the drilling and tapping process of hardened steels with bad machinability, like the AISI D2 steel, and this can make the process economically unfeasible if an extremely reduced cutting speed is not used. Generally, the drilling and tapping process of the AISI H13 can become economically viable, because the number of holes/threads achieved in accordance with the specified criteria was superior to the expected ones. In the cutting process of both materials (AISI D2 and H13), the main wear mechanism observed on the taps were abrasion, on the clearance surface, and adhesion, on the rake surface. This was severe for the first three threads of the tap.

Orientador: Alexandre Campane Vidal / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências / Made available in DSpace on 2018-08-25T17:39:31Z (GMT). No. of bitstreams: 1 CorreaNeto_Darcy_M.pdf: 10780036 bytes, checksum: a9e1aeacd891517e00b449caddbeb578 (MD5) Previous issue date: 2014 / Resumo: A exposição de um poço horizontal à formações geológicas perfuradas ocorre de forma diferente a exposição de um poço vertical à mesma formação. O poço horizontal atravessa as camadas geológicas de forma sub-paralelas, expondo estas camadas com uma extensão maior do que os poços verticais, que as atravessam de forma sub-perpendicular, formando exposições abruptas. Essa diferença de exposição afeta os perfis volumétricos, os perfis que compõe uma média dos 360º do poço, considerando um corte perpendicular a direção longitudinal do poço de forma diferente em relação aos perfis azimutais. Devido a esta diferença na exposição, é importante considerar métodos diferentes para a estimativa de Net Pay entre poços verticais e horizontais. Assim sendo, o objetivo deste trabalho foi o de utilizar perfis de densidade azimutais para diferenciar as estimativas de Net Pay. Para a consecução dos objetivos deste trabalho, foram feitos dois estudos. O primeiro deles consiste na utilização de perfis azimutais de densidade para gerar diferentes cálculos do Net Pay. Um segundo estudo compreendeu a análise de diferentes algoritmos de aumento de contraste de imagem, para auxiliar na identificação das feições geológicas, auxiliando na análise de Net Pay. Os perfis utilizados para a realização deste trabalho são de um poço produtor de óleo perfurado em um turbidito da costa leste brasileira. Neste poço, foi possível identificar algumas feições geológicas, como arenitos e folhelhos (camadas), cimentação carbonática e falha geológica. Como resultado do cálculo de Net Pay dos diferentes perfis de densidade analisados neste trabalho, foi possível identificar uma diferença de até 10,72% de Net Pay no mesmo poço. O Net Pay final das curvas de densidade volumétrica, densidade up, densidade down, conjunto da densidade up ou down e imagem obtiveram os seguintes resultados respectivamente: 88,42%, 91,44%, 89,86%, 96,62% e 99,14%. Quanto aos algoritmos de aumento de contraste, foram aplicados 14 algoritmos do domínio do espaço, possibilitando uma melhor visualização de contatos geológicos, falhas e camadas geológicas. Entre todos os algoritmos utilizados, os que apresentaram melhores resultados em imagem de densidade foram os algoritmos de derivada de 2ª ordem, corte dos níveis de cinza e histograma normalizado. Conclui-se portanto, que cada feição geológica encontrada ao longo do poço afeta os perfis azimutais e a imagem de densidade de forma diferente, portanto, a utilização dos diferentes perfis e dos algoritmos de aumento de contraste de imagem podem deflagar quais curvas de densidade devem ser utilizadas em determinadas profundidades do poço para obter o Net Pay mais preciso / Abstract: Drilled geological formation exposure are different considering horizontal and vertical wells. A horizontal well passes throught geological beds almost parallel, resulting in a wider exposure of the formation along the well path, while vertical wells passes through the same formation perpendicularly, resulting in abrupt contact between beds. This difference in exposure affects the volumetric well logs, logs that are composed by the average of the 360º of the well, considering a perpendicular cut of the longitudinal direction of the well. Due to this difference in exposure, it is important to consider difernet methos of estimation of Net Pay regarding vertical and horizontal wells. The objective os this work is to use azimuthal density logs to make diferent Net Pay estimations. To achieve the objectives of this project, two studies were made. The first study consists of the use of azimuthal density logs to generate diferent Net Pay estimations. The second, consists of the analysis of different image contrast enhancement algorithms to help on the identification of geological features, supporting the Net Pay analysis. The logs used on this work are from an oil productive well drilled in turbidites of the brazilian east coast. In this well, it was possible to identify a few geological features, such as sandstone and shale (beds), carbonate ciment and geological faults. As a result of the Net Pay calcualtion of the diferent density logs, it was possible to identify a difference of up to 10.72% Net Pay in the same well. The final Net Pay estimated from the volumetric density, up density, down density, up or down density and density image was respectively: 88.42%, 91.44%, 89.86%, 96.62% e 99.14%. Regarding the image contrast enhancement algorithms, 14 diferent algorithms from the space domain were applied to the selected density image, allowing a better visualization of several geological features, such as geological contacts, beds and faults. The algorithms that presented the best results in this image were the 2nd order derivative, gray level slicing and normalized histogram. Conclusions of this project are that each geological feature located at the well, affects the azimuthal and image logs in different ways, so, the use of different logs and image contrast enhancement algorithms can identify which density curves should be used in different depths of the well in order to obtain the most accurate Net Pay / Mestrado / Reservatórios e Gestão / Mestre em Ciências e Engenharia de Petróleo

Orientadores: José Ricardo Pelaquim Mendes, Kazuo Miura / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências / Made available in DSpace on 2018-08-19T05:58:26Z (GMT). No. of bitstreams: 1 Ifekaibeya_WalterNkemjika_M.pdf: 2900574 bytes, checksum: e8d362a13403f80acfb2bf870662e5fd (MD5) Previous issue date: 2011 / Resumo: Na área de petróleo & gás, devido aos altos custos das sondas utilizados nas atividades de perfuração no mar, o aumento da velocidade de execução das operações torna-se imprescindível. A necessidade de se reduzir esses altos custos tem feito com que empresas de perfuração busquem métodos que permitam alcançar o objetivo almejado. Uma dessas formas é o aumento da taxa de penetração (ROP) da broca. Contudo, segundo pesquisas, os efeitos obtidos através dessa prática nem sempre tem resultado na redução dos custos operacionais. Embora pertinente essa constatação, não foram desenvolvidos estudos que pudessem dizer a real influência da taxa de penetração da broca sobre os custos de construção de poços. Essa deficiência motivou o desenvolvimento desta dissertação, que possui como objetivo estudar a influência da taxa de penetração da broca sobre os custos de construção de poços utilizando informações obtidas através da análise da análise de Boletins Diário de Perfuração, dados de mudlogging, entre outros. Para facilitar a avaliação desenvolveu-se um novo parâmetro de análise baseado no tradicional e difundido custo métrico da broca / Abstract: In the field of oil and gas, due to the high costs of rigs used in drilling activities, increasing the speed of operations execution becomes essential. The need to reduce these costs has made drilling companies seek methods to achieve the desired objective. One of those ways is to increase the rate of penetration (ROP) of the bit. However, according to surveys, the outcomes achieved through this practice have not always result in lower operating costs. Although relevant, studies that could tell the real influence of bit's penetration on the costs of well construction were not developed. This deficiency has motivated the development of this dissertation, which has as objective to study the influence of penetration rates on the well construction costs by using information obtained from daily drilling reports analysis, mudlogging data, among others. To facilitate the evaluation influence of bit's penetration on the costs of well construction has developed a new parameter of analysis based on the traditional and popular cost per foot / Mestrado / Explotação / Mestre em Engenharia Mecânica

Masters of Science / Understanding the hydrogeology of fractured or crystalline rocks is complicated because of complex structure and a porosity that is almost exclusively secondary. These types of geologies exhibit strong heterogeneities and irregularities contrasted in hydraulic properties, spacing and flow direction within fractured rock aquifers. Therefore it is important to develop a conceptual model based on site specific data such as the hydraulic roles between groundwater and nearby hillslope/surface water bodies in order to understand its movement within the environment. Therefore this study intends to develop a hydrogeological conceptual model associated with the dominant groundwater flow processes at a 3rd order scale within the Kruger National Park (KNP).

The present master thesis deals with the application of workshop programming and advanced CAD / CAM technology to the design and production of differential holder and eccentric of Formula Student car. The first part characterizes and describes the technology of milling, drilling and boring. There is also a selection of material to be machined, including the characteristics of aluminium and its alloys. The following section describes the construction of differential holder and eccentric in the parametric program Autodesk Inventor and creation of CNC programs using the workshop programming and CAM of PowerMILL system. The conclusion section refers to the production of both components in the training centre BOSCH DIESEL s.r.o in Jihlava. The thesis is concluded with a technical-economic evaluation and analysis of both proposed production variants.

This Master’s thesis deals with non-contact methods of surface temperature with machining metal materials. This work contains summary of basic terms and description of thermodynamics laws. Furthermore, the work present criteria for selection suitable measuring equipment. In the second part of this work is described experiment focused on drilling technology and measurement dependence of temperature on different cutting speed for different drilling approaches. At the end are presented the results.

This document deals with the development of drilling tools by means of CAD and CAE technologies. At first, a brief overview of various design procedures of 3D drill models is presented, possibilities of measurement of force and moment loading during drilling are mentioned, a chip formation mechanism is briefly described and then a list of commonly used explicit (mesh) finite element methods used for cutting simulations is presented. A meshless SPH method have been selected for this work. Although it is able to handle the large deformations easily, it has been used for cutting simulations very rarely and only an orthogonal cutting simulations related information can be found in scientific databases. It has been demonstrated on the orthogonal cutting simulation of A2024-T351 alloy that was also the starting point for SPH simulation of drilling. The following is a decription of the design, simulation and prototyping of new drilling tools - drills with three and two cutting edges and an internal chip channel. This document is focused in detail on the variant with two cutting edges for which SPH drilling simulation has also been performed. Some drawbacks related to more precise chip simulation demands have been revealed, especially a rapid increase in number of SPH elements followed with prolongation of a computational time. Information related to the design of the drilling head with two cutting edges were then used to create the patent application.

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / This study aims to propose a new alternative to optimize drilling and blasting processes from the mathematical and geological viewpoint using simulation software. The main objective is to design a systematic model of steps that can generate a simulation through JkSimBlast. This simulation must represent the best alternative for the design of drilling mesh and explosive selection to be implemented in the field. To achieve this goal, a seven-step process diagram was proposed, including geology, design aspects (burden and spacing across the areas of influence algorithm), analysis of physical parameters such as detonation rate, drill-mesh design, explosives selection and fragmentation analysis, simulation tests that could represent the field designs, and selection of the most optimal simulation. For the collection of parameters in the field, we have used MicroTrap Software and WipFrag, which have allowed the design of a mesh according to the needs of the rocky massif. The most optimal simulation was implemented at Caravelí Mining Company-Estrella Unit and had a positive impact on the optimization of drilling and blasting, as the costs of these processes were reduced by 14.6%. Specifically, the costs of explosives were reduced by 2.6% and the costs of drilling steels by 10.4%. The performance of the loading machine advance/shot increased by 13.2% and 15.6%, respectively. Copyright 2019.

Boliden’s Garpenberg mine produces Zn-Pb-Ag(Cu-Au) using a sublevel stoping with pastefill mining method. The orebody is strongly affected by the existence of weakness zones mainly consisting of Talc Schist and Phlogopite Schist which affect the design, planning and production of the stope. To mine the ore two drifts, one below and one above the ore section, are excavated typically at a distance of 25 meters. Afterwards parallell longhole drilling is done for the primary stopes and drilling in a fan pattern is done for secondary stopes by automated remotely controlled SIMBA drills. Those drill rigs are equipped with sensors that record drilling parameters during drilling, so called Measurements While Drilling. The drilling parameters that are recorded are depth, time, penetration rate, percussive pressure, feed pressure, dampening pressure, rotation pressure and flush pressure at selected intervals. This thesis aims to identify the mentioned weakness zones using the existing MWD data. First of all, this thesis contains six chapters. The first is a detailed introduction to the problem. The second chapter describes the geology, the mining method used in Garpenberg and also includes a brief section on how SIMBA drills work. The third chapter consists of the MWD theory, literature review and the methodology used to come up with the solution of the stated problem. In the fourth chapter is described how a successful method was developed using 3D models created from MWD data and geologic maps to identify the weakness zones and classify the rock based on four filters created. The fifth chapter is a detailed discussion of the results and findings of this thesis. Finally, the sixth chapter is the conclusion.

Using greenhouse pot techniques, 32 drilling mud components were tested to see if, at a high rate of addition, they reduced plant growth. Green beans and sweet corn were the test plants. The excellent black, silt loam, slightly acidic, uncultivated Dagor soil (Cumulic Haploxeroll) was used for most tests. Rates used were considered to be abnormal level (high rate) and usual (low rate) amounts that might be added in commonly used drilling muds. Drilling mud components that caused no observable or statistically significant reductions of plant yield are the following: Super Visbestos, (Asbestos), asphalt, Ben-Ex (a vinyl acetate and maleic anhydride copolymer), bentonite, Cypan (sodium polyacrylate), DME (ethoxylated nonyl phenol), Super Lube Flow (gilsonite), paraformaldehyde, Separan-AP- 273 (Dow-made, Shell-supplied polymer), sodium acid pyrophosphate, and sodium carboxymethyl cellulose. Drilling mud components that barely caused a statistical significant (5 percent level) reduction in yield for only one of the two plant species when added to the soil only and, therefore, is of questionable hazard to plant growth are the following: Barite (BaSO4), Desco (modified tannin), Drillaid 412 (a filming amine), Drillaid 405 (diesel oil replacement), Kelzan-XC (a xanthan gum), Pipe dope, Lingo (lignite), Soltex (sulfonated asphalt?), and Witconnate 1840 (sulfonated tall oil). Drilling mud components causing significant reduction in plant growth mostly at only the high addition rates to soil-mud mixtures are the following: Desco (modified tannin?), Dextrid (a non-fermenting starch), pregelatinized starch, Q-Broxin (an iron chromelignosulfonate), Gendril Thik (guar gum), and Kwik-Seal. The most severe reductions in plant growth were caused by the following materials: Sodium hydroxide at the high rate (which was used in the soil-mud mixture with calcium lignosulfonate and with lignite), diesel oil and potassium chloride at both rates. The latter salt completely inhibited plant germination. Probable causes for plant growth reductions, photographic and visual records, and a discussion of the results is presented in some detail.