To provide technical support for sand control decision-making, it is necessary to predict the production condition at which sand production occurs. Sanding onset prediction involves simulating the stress state on the surface of an oil/gas producing cavity (e.g. borehole, perforation tunnel) and applying appropriate sand production criterion to predict the fluid pressure or pressure gradient at which sand production occurs. In this work, we present numerical and analytical poroelastoplastic stress models describing stress around producing cavity and verify those models against each other. Using those models, we evaluate the stress state on the cavity surface and derive sanding onset prediction models in terms of fluid pressure or pressure gradient based on the given sand production criterion. We then run field case studies and validate the sanding onset prediction models. Rock strength criterion plays important roles in sanding onset prediction. We investigate how the sanding onset prediction results vary with the selection of one or another rock strength criterion. In this work, we present four commonly used rock strength criteria in sanding onset prediction and wellbore stability studies: Mohr-Coulomb, Hoek-Brown, Drucker-Prager, and Modified Lade criteria. In each of the criterion, there are two or more parameters involved. In the literature, a two-step procedure is applied to determine the parameters in the rock strength criterion. First, the Mohr-Coulomb parameters like cohesion So and internal friction angle ff are regressed from the laboratory test data. Then, the parameters in other criteria are calculated using the regressed Mohr-Coulomb parameters. We propose that the best way to evaluate the parameters in a specific rock strength criterion is to perform direct regression of the laboratory test data using that criterion. Using this methodology, we demonstrate that the effect of various rock strength criteria on sanding onset prediction is less dramatic than using the commonly used method. With this methodology, the uncertainties of the effect of rock strength criterion on sanding onset prediction are also reduced.

Made available in DSpace on 2014-06-11T19:27:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-06-02Bitstream added on 2014-06-13T19:34:57Z : No. of bitstreams: 1 santiago_lff_me_guara_prot.pdf: 4253626 bytes, checksum: 2350418ac83b8b3472defb96b99e6028 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / No presente trabalho é válido o processo de lixamento da matéria de Pinus elliottii. O objetivo principal do estudo foi entender a influência e interação dos fatores de entrada (granulometria de lixa, velocidade de corte e pressão) sobre as variáveis de saída (taxa de remoção de material, temperatura, rugosidade, potência consumida, força de lixamento, emissão acústica e integridade superficial no processo de lixamento plano da madeira Pinus elliottii, processado paralelo às fibras. O lixamento foi realizado em uma lixadeira plana com sistema de monitoramento e aquisição de dados. Utilizou-se um delineamento de blocos completamente aleatorizados para a realização do experimento. Foram ulitizados quatro tipos de granulometrais de lixa, três velocidades de corte e três pressões, com seis repetições para cada combinação totalizando 216 tratamentos. Os resultados foram analizados através de uma análise de variância (ANOVA) com nével de significância de 5%. para taxa de remoção de material foi observado que a granulometria de lixa, pressão e velocidade influenciaram significativamente. Com relação à temperatura, somente a granulometria de lixa teve uma influência significativa no aquecimento do sistema. Para o acabamento superficial, apenas a granulometria de lixa influenciou significativamente na rugosidade. O consumo de potência foi influenciado pela velocidade de corte e pressão. Para a força de lixamento, a granulometria de lixa e a pressão influenciaram significativamente. Na emissão acústica somente a granulometri de lixa influenciou significativamente no sinal captado. Para a análise de imagens foram observados diferenças no acabamento conforme se aumenta a granulometria da liza. Não foi observada nenhuma interação significativa entre os fatores velocidade de corte e pressão para todas as variáveis de saída estudadas / This study refers to about sanding process of Pinus elliottii wood following the direction of grain. The first aim of this work is trying to undersand the influence of the following factors: belt speed, pressure and grit size on the output parameters of material remove rate, temperature, roughness, image, analysis, cutting force, power consumption and acoustic emisson. It was used a sanding belt with a data acquisition system to record the output variables. For the experiment it was used a randomized block design. The level of factors consider in the experiment it were four size of grit, three levels of pressure and three levels of belt speed. The experiment total treatments of belt speed, pressure and grit size (3 x 3 x 4=36 ) was run with six replicates for a total 216 expeiments. The results of output parameters were analyzed through the analysis of variance (ANOVA) with level of significance 5%. All the factors were significant to material remove rate. Only grit sizes were significant to the differnt levels temperature. The same behavior it was observed to the roughness where only grits size were significant. Differently the power consumption was not significant to the grits size but it was significant to the levels of pressure and belt speed. It was observed that grits sizes and pressure caused significant influence on cutting force. Only grits size significant to the acoustic emission. It was observe on analysis of image that the coarse grit produces a rougher surface than the smooth grit and anatomical elements showed up more when smooth grit was used. It could not found any interaction between the factors to all outputs parameters

Orientador: Manoel Cleber de Sampaio Alves / Coorientador: Marcos Tadeu Tiburcio Gonçalves / Banca: Marcos Valério Ribeiro / Banca: Eduardo Carlos Bianchi / Resumo: No presente trabalho é válido o processo de lixamento da matéria de Pinus elliottii. O objetivo principal do estudo foi entender a influência e interação dos fatores de entrada (granulometria de lixa, velocidade de corte e pressão) sobre as variáveis de saída (taxa de remoção de material, temperatura, rugosidade, potência consumida, força de lixamento, emissão acústica e integridade superficial no processo de lixamento plano da madeira Pinus elliottii, processado paralelo às fibras. O lixamento foi realizado em uma lixadeira plana com sistema de monitoramento e aquisição de dados. Utilizou-se um delineamento de blocos completamente aleatorizados para a realização do experimento. Foram ulitizados quatro tipos de granulometrais de lixa, três velocidades de corte e três pressões, com seis repetições para cada combinação totalizando 216 tratamentos. Os resultados foram analizados através de uma análise de variância (ANOVA) com nével de significância de 5%. para taxa de remoção de material foi observado que a granulometria de lixa, pressão e velocidade influenciaram significativamente. Com relação à temperatura, somente a granulometria de lixa teve uma influência significativa no aquecimento do sistema. Para o acabamento superficial, apenas a granulometria de lixa influenciou significativamente na rugosidade. O consumo de potência foi influenciado pela velocidade de corte e pressão. Para a força de lixamento, a granulometria de lixa e a pressão influenciaram significativamente. Na emissão acústica somente a granulometri de lixa influenciou significativamente no sinal captado. Para a análise de imagens foram observados diferenças no acabamento conforme se aumenta a granulometria da liza. Não foi observada nenhuma interação significativa entre os fatores velocidade de corte e pressão para todas as variáveis de saída estudadas / Abstract: This study refers to about sanding process of Pinus elliottii wood following the direction of grain. The first aim of this work is trying to undersand the influence of the following factors: belt speed, pressure and grit size on the output parameters of material remove rate, temperature, roughness, image, analysis, cutting force, power consumption and acoustic emisson. It was used a sanding belt with a data acquisition system to record the output variables. For the experiment it was used a randomized block design. The level of factors consider in the experiment it were four size of grit, three levels of pressure and three levels of belt speed. The experiment total treatments of belt speed, pressure and grit size (3 x 3 x 4=36 ) was run with six replicates for a total 216 expeiments. The results of output parameters were analyzed through the analysis of variance (ANOVA) with level of significance 5%. All the factors were significant to material remove rate. Only grit sizes were significant to the differnt levels temperature. The same behavior it was observed to the roughness where only grits size were significant. Differently the power consumption was not significant to the grits size but it was significant to the levels of pressure and belt speed. It was observed that grits sizes and pressure caused significant influence on cutting force. Only grits size significant to the acoustic emission. It was observe on analysis of image that the coarse grit produces a rougher surface than the smooth grit and anatomical elements showed up more when smooth grit was used. It could not found any interaction between the factors to all outputs parameters / Mestre

No description available.

The growing interest in the industrialization of construction process; promotes opportunities for automation. Automation brings improvement in quality and productivity, while reducing worker’s exposure to hazardous work environments. The integration of robotics in interior finishing works, such as sanding and painting of drywalls is a relatively new concept. Progressing to a stage where fully autonomous robots are used for interior finishing works requires intermediate steps; namely surface profiling. This thesis describes a theoretical concept of shadow profilometery to profile the surface of an installed drywall. A shadow was cast over the area under consideration, and the shadow profile was captured as a 2D image by a camera. Digital image processing techniques were utilized for identifying regions that deviate from a flat surface. The methodology discussed in this research, was tested on a virtual system, and the results were found to be encouraging. / Construction Engineering and Management

The types of wood identified from tree -ring specimens of 78 archaeological sites in the area of Flagstaff, Arizona were analyzed for changes through time. The sites span a period from Basketmaker III through Pueblo III times. Most of the specimens are from constructional materials. The wood identifications were also compared with the tree types growing on the sites today (1960). The analyses show that there is a great uniformity of types of wood used and the relative percentages of the various woods throughout the time span. This uniformity exists regardless of the location of the site geographically, or in relation to the modern tree distribution. Only the sites constructed during Pueblo I times are different. This group is restricted to the present ponderosa pine limits, and they did not yield a single specimen of either juniper or oak, both of which are found in all the other time divisions. Douglas fir, ponderosa pine, piñon pine and Populus sp. occur in relatively consistent percentages throughout the time span, despite the change in dwelling type from pithouses to pueblos. Since the Indians used trees other than those closest at hand for building purposes, they had to haul large quantities of wood from the areas where the trees grew. Distances to the nearest places where the wood types can be found today are as much as 15 miles from the sites. Some strong motivation must have inspired so great an expenditure of effort, but the reason is not apparent.

Submitted by Sueli Souza Leite null (leitess@bol.com.br) on 2016-04-12T20:03:45Z No. of bitstreams: 1 1000.pdf: 2835888 bytes, checksum: 43aa2f9aeb4c2f1b54f42d927c0da040 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-04-15T14:06:36Z (GMT) No. of bitstreams: 1 leite_ss_me_bauru.pdf: 2835888 bytes, checksum: 43aa2f9aeb4c2f1b54f42d927c0da040 (MD5) / Made available in DSpace on 2016-04-15T14:06:36Z (GMT). No. of bitstreams: 1 leite_ss_me_bauru.pdf: 2835888 bytes, checksum: 43aa2f9aeb4c2f1b54f42d927c0da040 (MD5) Previous issue date: 2016-02-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O lixamento da madeira envolve inúmeras variáveis as quais influenciam na qualidade superficial da peça produzida, tornando-se por isso, um processo complexo. Atua de forma imprescindível nas indústrias, principalmente fabricantes de móveis, painéis, molduras, esquadrias e dentre outras. Entretanto, é tratado de forma empírica, prejudicando a qualidade do produto e elevando os custos de produção, visto que é, um dos processamentos mais caros na indústria de madeira. Sabido disto, este trabalho, teve por objetivo combinar um conjunto de fatores para padronizar o processo de lixamento. Para isto, seguiu o planejamento experimental de Taguchi, método baseado em conceitos estatísticos, responsável por diagnosticar o conjunto de fatores que propiciam o alcance da qualidade do produto final. A experimentação realizou-se em relação a uma matriz ortogonal L8, criando assim, oito condições diferentes de lixamento, repetindo-as três vezes cada, totalizando em 24 ensaios. Variou os níveis dos seguintes fatores: granulometria, grão abrasivo, sentido do lixamento e espécie da madeira, com o intuito de analisar o comportamento dos parâmetros: emissão sonora, potência, rugosidade, taxa de remoção e temperatura no decorrer do processo. Por meio da análise de variância (ANOVA), concluiu-se que o comportamento dos parâmetros foram influênciados pelos fatores estipulados, os quais interferiram na qualidade superficial da madeira. / The sanding of wood involves numerous variables which influence the surface quality of the produced piece, becoming therefore a complex process. It is a crucial process in industries, particularly manufacturers such as furniture, panels, moldings, frames and others. However, the process is trated empirically, decreasing the product quality and increasing production costs, since it is one of the most expensive processes in the wood industry. According to this, this paper, aimed to standardize a set of factors to achieve the best surface finish of the wood. For this, the following experimental design Taguchi method based on statistical concepts, responsible for diagnosing the set of factors that promote the achievement of the quality of the final product. The experiment was performed in relation to a matrix L8 orthogonal matrix, creating eight different conditions sanding, repeating three times each, totaling in 24 trials. Varied levels of the following factors: particle size, abrasive grain, sense of sanding and timber species, in order to analyze the parameters of behavior, noise emission, power, roughness, temperature and removal rate in the process. Through analysis of variance (ANOVA), it was concluded that the behavior parameters were influenced by prescribed factors which interfere in the surface quality of the wood.

Resumo: O processo de lixamento da madeira é uma prática comum para preparar sua superfície para o revestimento. A qualidade superficial da madeira é diretamente relacionada ao revestimento, aderência, custos de pós processamento e aparência estética do produto. Vários parâmetros influenciam no acabamento superficial da madeira como: espécie de madeira, processo de usinagem e granulometria da lixa. Nesta tese foram coletados dados de rugosidade superficial de amostras das espécies Eucalyptus grandis e Eucalyptus citriodora usinadas em torno tubular em três velocidades de avanço (10, 14 e 18m/min.) e lixadas em lixadeira de cinta vertical dupla por quatro jogos de lixas abrasivas de alumínio zirconado. Estes jogos foram compostos com lixas de granulometrias 80, 100 e 120 (80-100, 80-120, 100-120 e U80-120), sendo a primeira lixa para desbaste e a segunda para acabamento. Concluiu-se que para os três conjuntos de lixas novas empregadas, o conjunto de lixas de granulometrias 80 e 120, para desbaste e acabamento, respectivamente, foi aquele que apresentou o melhor desempenho quanto ao acabamento superficial para as duas espécies. O emprego de lixas usadas não demonstrou perda significativa de rendimento se comparadas às demais combinações de lixas novas. O conjunto de lixas 80-120 apresenta, numa razão proporcional, uma variação de 4% no valor de "Ra" para cada 4 m/min aumentado na velocidade de avanço do torneamento das amostras. Pode-se afirmar que, em condições ótimas de lixamento, em média, a cada 0,1mm/rot de aumento no avanço por dente no torneamento, tem-se o aumento de 1% em "Ra". / Abstract: The process of sanding the wood is a common practice to prepare the surface for coating. The surface quality of wood is directly related to the coating, adhesion, costs of post-processing and aesthetic appearance of the product. Several parameters influence the surface finish of the wood as wood species, machining process and particle size of sandpaper. In this thesis the analysis was based on data collected in surface roughness of samples of species Eucalyptus grandis and Eucalyptus citriodora machined in tubiform lathe three feed rate (10, 14 and 18m/min.) and sanded in double vertical belt sander by and four sets of abrasive zirconia aluminium. These sets were composed with grain sizes 80,100 and 120 mesh (80-100, 80-120, 100-120 e U80- 120), the first sandpaper for roughing and second for finishing. It was concluded that for the three new sets of sandpaper used, the combination of grit sizes of 80 and 120, for roughing and finishing, respectively, presented the best performance on the surface finishing for both species. The use of worn sandpaper showed no significant loss of income compared to the other combinations of new sandpaper. The set of sandpaper 80-120 provides, in proportion to a variation of 4% in the value of "Ra" for each 4 m/min increased the feed rate speed of the turning of the samples. Thus, can be conclude that, under optimal conditions of sanding, on average, every 0.1 mm/rev increased in feed per tooth, increases of 1% in "Ra". / Orientador: Marcos Valério Ribeiro / Coorientador: Marcos Tadeu Tiburcio Gonçalves / Banca: Manoel Cleber de Sampaio Alves / Banca: Edson Cocchieri Botelho / Banca: Ivaldo de Domenico Valarelli / Banca: Francisco Antonio Rocco Lahr / Doutor

This master's thesis is engaged in development of new sanding units for a specific type of rail vehicle. Sanding in rail transport is application of most commonly silica sand into wheel-rail contact. Thanks to its reliability it is still the most widely used method for removing contaminants and improving adhesion in that contact. Sanding devices were developed in cooperation with corporation, which deals with production of rail transport equipment, among other things. The most important part of sanding device is sand dispenser. Dispensers were experimentally developed at the test station in the cooperating corporation. Dispensers were tested for utilization conditions on the locomotive of the train and conditions for trams and light rail vehicles. Furthermore, sand boxes have been designed for specific type of rail vehicle and new type of sand discharge tube, which directs sand directly into wheel-rail contact was designed too.

Cranes are used to lift and move large objects in a wide variety of applications at constructions sites, shipping ports, and manufacturing facilities, etc. If the load to be moved is too long or heavy for a single crane, then two, or more, cranes must work in cooperation to move the payload. In a factory setting this can be accomplished using two trolleys running along the same bridge forming a dual hoist crane. Using two hoists not only increases lifting capacity, it also improves stability of the payload over traditional single hoist configurations. This research takes advantage of that increased stability and explores a novel application for dual hoist cranes: suspending a robot arm from the two trolleys. This increases the workspace of the robot to the entirety of the space covered by the crane, opening up numerous applications not possible with a stationary robot. In order to better understand and characterize the dynamics of the system, a numerical model was developed and tested against a physical system to confirm its validity. A vision system has the potential to greatly increase the usefulness of a robotic system such as the one presented in previous paragraph. The Asus Xtion was used in this work due to its versatility and low cost. An evaluation of this sensor was performed. Various tests were conducted to determine its accuracy in a range of scenarios. It was found that crane oscillations degraded the quality of data returned. This is effect is especially detrimental if the crane is moved to a specified point and sensing begins immediately. The data collection process could be delayed until the residual oscillations subside, however the time penalty incurred by waiting is large because the oscillations are lightly damped and have a long period. To address this issue a control method called input shaping was introduced to reduce the residual oscillations thereby increasing the quality of the sensor data. Finally, two promising uses of the robot arm dual-hoist crane system were introduced: painting and sandblasting. The efficiency of a factory equipped with this system can be increased at relatively low cost by automating manual tasks such as these.