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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.
11

Traktoriaus ir priekabos su varančiaisiais ratais kinematinio suderinamumo tyrimas / Kinematic compatibility of tractors and trailers with all weel drive system

Patašius, Irmantas 28 May 2012 (has links)
Darbo tikslas: ištirti transporto priemonės sudarytos iš traktoriaus ir priekabos su varančiaisiais ratais kinematinį suderinamumą, dinaminius bei ekonominius rodiklius ir nustatyti racionalios eksploatacijos sąlygas. Darbe nagrinėjami transporto priemonės sudarytos iš traktoriaus ir priekabos su varančiaisiais ratais kinematinis suderinamumas, dinaminiai bei ekonominiai rodikliai, esant išjungtiems priekabos varantiesiems tiltams bei įjungtiems vienam ir dviem priekabos varantiesiems tiltams. Nustatyta, kad transporto priemonei, važiuojant suartu lauku, kurio drėgnis 5 cm gylyje - 19,8 %, kietis - 0.85 MPa, o kietis 15 cm gylyje - 1,08 MPa, racionalu įjungti tik vieną priekabos varantįjį tiltą (kartu su traktoriaus užpakaliniu varančiuoju tiltu). Čia vieno priekabos varančiojo tilto įjungimas duoda teigiamus rezultatus važiuojant tiek su 4500 kg kroviniu, tiek ir be krovinio. Važiuojant vėžėmis per suarta dirvą be krovinio yra racionalu abu priekabos varančiuosius tiltus išjungti, o vežant krovinį įjungti vieną priekabos varantįjį tiltą. / Work aim: To investigate a vehicle consisting of a tractor-trailer-wheel drive with the compatibility of kinematic, dynamic and economic indicators and the rational exploitation conditions. The work deals with a vehicle consisting of a tractor and trailer with wheel drive . Kinematic compatibility, dynamic and economic indicators ,when the trailer driwing axles is off and on. It was found that a motor vehicle while driving convergence field, the moisture content at a depth of 5 cm - 19.8%, hardness - 0.85 MPa, and hardness at a depth of 15 cm - 1.08 MPa, it is reasonable to activate only one trailer driving axle the drive (with drive to the rear axle). This single drive axle trailers activation produce positive results in driving the 4500 kg load or without load. Going through the tracks plowed soil without load is reasonable to both drive axles off the trailer and cargo transport trailers for the drive to activate a axle.
12

As influências do eixo de desenvolvimento da rodovia Washington Luiz na estruturação econômica do município de Itápolis/SP /

Bordo, Adilson Aparecido. January 2006 (has links)
Orientador: Eliseu Savério Sposito / Banca: Marcos Kazuo Matushima / Banca: Paulo Fernando Cirino Mourão / Resumo: Os eixos de desenvolvimento referem-se às grandes vias de circulação de pessoas, mercadorias, bens, serviços e informações, balizados por uma rede de centros urbanos, e que estimulam a localização das atividades industriais. No Estado de São Paulo, os eixos de desenvolvimento podem ser visualizados ao longo de importantes rodovias que fazem a ligação da metrópole paulista com o interior e que funcionaram como canais para a desconcentração urbano-industrial que se iniciou na década de 1970 e se intensificou na década de 1980. O eixo da rodovia Washington Luiz (trecho Araraquara São José do Rio Preto), duplicado no início da década de 1990, somente nos últimos anos passa a atuar como um dos fatores de localização industrial para o município de Itápolis na atração de algumas indústrias desconcentradas de outras regiões. No entanto, a maioria das indústrias de Itápolis é de capital local (70,37% das indústrias pesquisadas). Os principais ramos industriais observados na pesquisa foram as agroindústrias e as confecções. São indústrias classificadas como tradicionais ou de trabalho intensivo e estão ligadas aos antigos fatores de localização industrial, como a proximidade das matériasprimas e a disponibilidade de mão-de-obra. A economia de Itápolis é baseada fundamentalmente na agropecuária. O município possui o maior PIB agrícola do Brasil e foi responsável por 0,6% de toda a produção agrícola brasileira em 2002. Em 2003, a participação de Itápolis no valor adicionado da agricultura estadual foi de 1,8%. A citricultura é responsável pela geração de 80% do ICMS. O dinamismo da agricultura constitui-se em um importante atrativo para a atividade industrial, seja...(Resumo completo, clicar no acesso eletrônico abaixo) / Abstract: Development axles refer to big circulation routes of people, goods, services and information marked out by a network of urban centers, which foster industrial activities location. In the State of São Paulo, these development axles can be seen along important freeways that connect the capital with the country and they worked as channels for urban-industrial concentration changes, which began in the 70's and became stronger in the 80's. The axle of Washington Luiz freeway (between the cities of Araraquara and São José do Rio Preto), which was doubled at the beginning of the 90's, has only contributed to attract some industries from other areas to the district of Itápolis in the last few years. However, most of the industries in the town were born with local investment (70.37% of the ones researched). The main industrial branches observed were agriculture-industry and clothes. They can be considered traditional or intensive work and are linked to old factors of industrial location, such as being close to raw materials and work force availability. Itápolis economy is essentially based in agriculture. The district has the highest agricultural GDP of Brazil, being responsible for 0.6% of the Brazilian agricultural production in 2002. In 2003, its participation in the state agriculture was 1.8%. The citrus culture is responsible for producing 80% of ICMS (Brazilian tax over goods and services movement). A dynamic agriculture fully attracts industrial activity in the...(Complete abstract, click eletronic address below) / Mestre
13

Análise da paisagem no entorno dos eixos viários: o exemplo do Rodoanel Mario Covas na RMSP / Landscape analysis over the road axles proximities: the example of Mario Covas Expressway on RMSP

Larissa Lucciane Volpe 23 November 2009 (has links)
A construção de uma rodovia pode interferir na dinâmica urbana, transformando a paisagem em seu entorno, e isto pode ocorrer devido a diversos fatores como instalações de empreendimentos, novas ocupações residenciais, mudanças na dinâmica e na fisionomia das áreas já ocupadas. Neste trabalho, o objetivo do estudo da paisagem urbana ao longo de um eixo viário, que tem como função interligar outras rodovias, é analisar de que forma ocorrem as alterações na paisagem urbana e sua abrangência. O estudo das transformações da paisagem urbana no entorno do eixo viário Rodoanel trecho oeste nos bairros de Perus e Jaraguá na cidade de São Paulo foi trabalhada por meio de levantamento de dados de diversas fontes e utilização de geotecnologias. As geotecnologias unidas às informações provenientes de documentos e trabalhos de campo, auxiliaram na organização, gerenciamento e quantificação dos dados. Os resultados obtidos foram organizados nos mapas temáticos de área construída, área verde densa, gramínea e árvores esparsas, área de solo exposto e galpões. Estes mapas temáticos permitiram uma caracterização de um cenário no entorno do trecho oeste do Rodoanel Mario Covas nos bairros Perus e Jaraguá, com as alterações ocorridas desde o ano de 1994 até 2002, isto é, uma análise temporal. Para alcançar estes resultados foi trabalhado em ambiente SIG dois tipos de classificação digital, a analógica e a automática, sendo o método analógico realizado na imagem IKONOS e também nas fotografias aéreas; e o método automático realizado apenas na imagem de alta resolução IKONOS. Foram comparados os dois métodos e observado que a classificação analógica foi mais adequada para a realização da análise multitemporal por ter sido realizada da mesma forma nas duas fontes, nas fotos aéreas de 1994 e na imagem IKONOS de 2002; e também permitiu uma melhor visualização nos mapas temáticos por considerar áreas maiores que a classificação automática. Com a análise temporal foi possível concluir que, do ano de 1994 ao ano de 2002, a área verde densa aumentou, a área de gramínea e árvores esparsas diminuiu, a área de solo exposto diminuiu, a área construída aumentou e a área de galpões de 1984 a 2002 também aumentou. As imagens aéreas de 1994 e 2002 também foram comparadas com os trabalhos de campo realizados nos anos de 2006, 2007, 2008 e 2009, onde foi possível observar as transformações ocorridas neste período. Nesta análise, os resultados foram divididos em alterações positivas, neutras e negativas, como sugere relatório desenvolvido pela empresa responsável pela construção do trecho oeste do Rodoanel Mario Covas, e de acordo com as observações realizadas em campo e no âmbito bibliográfico. Concluiu-se aproximadamente 48% de alterações consideradas negativas, 41% positivas e 12% neutras na área de estudo. / The construction of a highway may interfere on the urban dynamics and transform the landscape in its surroundings and this might occur due to several factors as installations of new undertakings, new residential constructions, changes on the dynamics and appearance in already occupied areas. In this work, the objective in the study of the urban landscape on the surroundings of a expressway axle, that have the function to link other highways, is to analyze in which way the landscape changes occur and its range. The transformations study of the urban landscape on the surroundings of the Mario Covas Expressway, east part, on the districts of Perus and Jaraguá, was developed through the gathering of data from several sources and the use of geotechnologies. The geotechnologies united to the data from documents and field works, aided the organization, managing and quantification of the data. The results obtained were organized on thematic maps of the built area, dense green area, grass and sparse trees, exposed soil and warehouses. These thematic maps allowed a characterization of the surroundings scenario of the East part of the Mario Covas Expressway on the São Paulo districts of Perus an Jaraguá, with a temporal analysis of the changes that took place from the year of 1994 through 2002. To reach these results two types of digital classification were worked over a GIS environment: the analogic and the automatic, being the analogical method constructed over the IKONOS imagery and also over aerial photographs; and the automatic method constructed exclusively over the IKONOS high resolution imagery. The two methods were compared and observed that the analogic classification was more suited to the multitemporal analysis due to the use of the same methods on both sources, on 1994 aerial imagery and 2002 high resolution imagery; and also allowed a better visualization on the thematic maps for considering larger regions than the automatic classification. With the multitemporal analysis was possible to conclude that, from 1994 through 2002 year, the dense green area increased, the grass and sparse tree area decreased, the exposed soil area decreased, the constructed area increased and warehouses area, from 1984 to 2002 also increased. The aerial images from 1994 and 2002 also were compared with the field work developed on 2006, 2007, 2008 and 2009, where was possible to observe the transformations that took place throughout this period. In this analysis, the results was divided in positive, neutral and negative alterations, as suggests report developed by the responsible company for the construction of the East part of the Mario Covas Expressway and according to the observations carried out on the field and over the bibliography extent. The conclusion is that approximately 48% of the transformations are considered negative, 41% positive and 12% neutral over the study area.
14

Odpružení přední hnané nápravy traktoru lehké řady / The springing of front driving axle in lightweight type tractor

Vodrada, Tomáš January 2013 (has links)
The topic of this thesis is springing of front driving axle design in Zetor tractor of series Proxima including FEM analysis. The thesis also deals with study of currently used suspended front axles produced by word known manufacturers.
15

Investigations on the efficiency of truck axles and their hypoid gear set : A thermo-mechanical model / Étude du rendement des ponts de camion et de leur couple conique : Un modèle thermomécanique

Fossier, Charlotte 14 March 2018 (has links)
Pour répondre au besoin des clients ainsi qu’aux réglementations gouvernementales, les constructeurs de camions doivent diminuer la consommation et les émissions de leurs véhicules. Une solution-clé est d’améliorer le rendement de la transmission du camion, dont le pont fait partie. Leur design n’a longtemps été optimisé qu’en fonction de critères de durabilité et de bruit. L’objectif de ce travail est donc de caractériser le rendement des ponts de camion. La dissipation de puissance au sein du pont est causée par l’engrènement, les roulements, les joints et le barbotage. Des méthodes permettent d’estimer globalement ces pertes de puissance, mais elles ne sont pas forcément adaptées aux ponts. En effet, l’élément principal du pont est un engrenage spiro-conique ou hypoïde et son importance est étudiée : sa forme influe sur le barbotage, tandis que sa géométrie de denture et sa cinématique gouvernent le frottement à l’engrènement. Il semble ainsi important d’évaluer le frottement de ces couples coniques par une approche locale et d’étudier l’influence des paramètres de denture. Cependant, les pertes de puissance dépendent de la température, via les propriétés de l’huile. Des expériences montrent un important écart de température entre les composants. Il faut donc considérer des températures locales plutôt qu’une température d’huile globale. Le rendement et la durabilité peuvent être impactés par des points chauds. La méthode des réseaux thermiques permet de modéliser les échanges thermiques du pont ainsi que la distribution de températures. Les tests classiques de rendement mesurent uniquement la perte globale et la température d’huile : rien ne permet de confirmer la répartition des pertes entre sources. Une campagne d’essais avec mesures de température est donc réalisée et valide le modèle pour le calcul des températures locales et pour l’estimation des pertes de chaque composant. Ce modèle peut alors être utilisé lors du design de futurs ponts. / To fulfil customer demands, but also government regulations, the truck industry must decrease the fuel consumption and emissions of its vehicles. A key development is to improve the efficiency of the powertrain, which includes the axle. Until recently, optimisation of axle design has mainly concerned durability and noise aspects. The aim of this study is then to characterise the efficiency of truck axles. As for most of the mechanical transmissions, power dissipation in axles is due to gear mesh, rolling element bearings, seals and oil churning. Formulae already exist to estimate these power losses at a global level, but they are not always adapted to axles. Indeed, the main component of axles is a spiral bevel or a hypoid gear set. The influence of these special gears on efficiency is investigated here: their shape drives oil churning losses, while their tooth geometry and their kinematics impact friction at gear mesh. Therefore, the meshing friction of the gear set is also evaluated thanks to a local approach. The influence of some gear parameters is studied. However, power losses are influenced by temperature through oil viscosity. As previous experiments underline non-negligible temperature difference between components, it is necessary to consider local temperatures instead of a global oil temperature. Efficiency but also durability can be impacted by local hot spots. The thermal network method is used to model the thermal exchanges inside and outside the axle and to calculate temperature distribution. Usual efficiency tests on axles measure only global power loss and oil temperature: no evidence allows to confirm a power loss breakdown. Thus, a test campaign with temperature measurements is done and validates the model on local temperature calculation but also on estimation of component power losses. The model can be used at design stage for future development of axles.
16

As influências do eixo de desenvolvimento da rodovia Washington Luiz na estruturação econômica do município de Itápolis/SP

Bordo, Adilson Aparecido [UNESP] 11 December 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-12-11Bitstream added on 2014-06-13T19:16:21Z : No. of bitstreams: 1 bordo_aa_me_prud.pdf: 2274588 bytes, checksum: e1175d5a0b4d8625ddf5307e742f634b (MD5) / Os eixos de desenvolvimento referem-se às grandes vias de circulação de pessoas, mercadorias, bens, serviços e informações, balizados por uma rede de centros urbanos, e que estimulam a localização das atividades industriais. No Estado de São Paulo, os eixos de desenvolvimento podem ser visualizados ao longo de importantes rodovias que fazem a ligação da metrópole paulista com o interior e que funcionaram como canais para a desconcentração urbano-industrial que se iniciou na década de 1970 e se intensificou na década de 1980. O eixo da rodovia Washington Luiz (trecho Araraquara São José do Rio Preto), duplicado no início da década de 1990, somente nos últimos anos passa a atuar como um dos fatores de localização industrial para o município de Itápolis na atração de algumas indústrias desconcentradas de outras regiões. No entanto, a maioria das indústrias de Itápolis é de capital local (70,37% das indústrias pesquisadas). Os principais ramos industriais observados na pesquisa foram as agroindústrias e as confecções. São indústrias classificadas como tradicionais ou de trabalho intensivo e estão ligadas aos antigos fatores de localização industrial, como a proximidade das matériasprimas e a disponibilidade de mão-de-obra. A economia de Itápolis é baseada fundamentalmente na agropecuária. O município possui o maior PIB agrícola do Brasil e foi responsável por 0,6% de toda a produção agrícola brasileira em 2002. Em 2003, a participação de Itápolis no valor adicionado da agricultura estadual foi de 1,8%. A citricultura é responsável pela geração de 80% do ICMS. O dinamismo da agricultura constitui-se em um importante atrativo para a atividade industrial, seja... / Development axles refer to big circulation routes of people, goods, services and information marked out by a network of urban centers, which foster industrial activities location. In the State of São Paulo, these development axles can be seen along important freeways that connect the capital with the country and they worked as channels for urban-industrial concentration changes, which began in the 70's and became stronger in the 80's. The axle of Washington Luiz freeway (between the cities of Araraquara and São José do Rio Preto), which was doubled at the beginning of the 90's, has only contributed to attract some industries from other areas to the district of Itápolis in the last few years. However, most of the industries in the town were born with local investment (70.37% of the ones researched). The main industrial branches observed were agriculture-industry and clothes. They can be considered traditional or intensive work and are linked to old factors of industrial location, such as being close to raw materials and work force availability. Itápolis economy is essentially based in agriculture. The district has the highest agricultural GDP of Brazil, being responsible for 0.6% of the Brazilian agricultural production in 2002. In 2003, its participation in the state agriculture was 1.8%. The citrus culture is responsible for producing 80% of ICMS (Brazilian tax over goods and services movement). A dynamic agriculture fully attracts industrial activity in the...(Complete abstract, click eletronic address below)
17

A problemÃtica do remanso dos eixos de macrodrenagem nas galerias urbanas: estudo de caso sobre a modelagem da cheia do Rio Poty no ano de 2009 em Teresina-PI / The problem of backwater of macro drainage shafts in urban galleries: study case on the modeling of the full Rio Poty in 2009 in Teresina, PI

Maria Josà Carvalho Silva 27 November 2014 (has links)
A cidade de Teresina, capital do estado do PiauÃ, à entrecortada pelos rios ParnaÃba e Poty, sendo o Ãltimo afluente ao primeiro, dentro da zona urbana de Teresina. O rio ParnaÃba controla uma bacia hidrogrÃfica de 237.000 km a montante de Teresina, enquanto que o rio Poty, controla uma bacia hidrogrÃfica de 51.400 kmÂ. A caracterÃstica hidrolÃgica principal das cheias nos rios ParnaÃba e Poty à que as enchentes do rio ParnaÃba sÃo passiveis de controle parcial a partir das comportas da Usina HidroelÃtrica (UHE) Boa EsperanÃa, ao passo que, tal controle inexiste para as cheias advindas da bacia do rio Poty. O presente estudo analisou a questÃo da interferÃncia das cheias do rio Poty com o sistema de microdrenagem formado pelas galerias urbanas transversais afluentes ao mesmo, constatando a possibilidade de afogamento e remanso do rio Poty sobre as galerias em determinadas condiÃÃes de cheias hidrolÃgicas. Foi analisado o caso da cheia do ano de 2009 no sistema de drenagem transversal ao rio Poty, que causou a inundaÃÃo de diversos bairros, em virtude do remanso decorrente da elevaÃÃo da cota do nÃvel d Ãgua do rio Poty acima da cota das geratrizes superiores das galerias transversais. Foi constatado que, em virtude das cotas de desague das galerias do bairro Primavera no rio Poty, as cheias deste rio com perÃodo de retorno bianual (TR = 2 anos), sÃo suficientes para promover o fluxo inverso no sistema de galerias e a inundaÃÃo de Ãreas urbanas conectadas. Conclui-se que hà necessidade de intervenÃÃes estruturais para solucionar este problema, a partir, ou do controle das cheias no rio Poty por meio de reservatÃrio de retenÃÃo, tal como a futura barragem Castelo do PiauÃ, ou a partir de emprego de bacias de detenÃÃo urbanas, comportas de marà e sistema de bombeamento das Ãguas pluviais das bacias interconectadas com o rio Poty. / The city of Teresina, Piauà state capital, is intersected by rivers ParnaÃba and Poty, the last tributary to the first, within the urban area of ​​Teresina. The ParnaÃba River controls a watershed of 237,000 square kilometers upstream of Teresina, while the river Poty, controls a watershed of 51,400 kmÂ. The main hydrological characteristic of floods in the ParnaÃba and Poty rivers is that ParnaÃba River floods are likely to partial control from the gates of Hydroelectric Power Plant (HPP) Good Hope, whereas such control does not exist to floods arising from the Poty River basin. This study examined the question interference flooding of Poty river with minor drainage system formed by affluent urban galleries cross the same, noting the possibility of drowning and backwater Poty river on the galleries certain conditions of hydrological floods. Analyzed the case of the full 2009 in the transverse drainage system to Poty River, which caused the flood diverse neighborhoods, because of backwater due to the increase of share of the Poty river water level d greater than the level of the upper generating lines of the galleries cross. It was found that, because of desague quotas of galleries Spring neighborhood in Poty river, the floods of the river with two-year return period (TR = 2 years), are sufficient to promote the reverse flow in the gallery system and the Flood connected urban areas. It is concluded that there is need for structural measures to solve this problem, from, or control of Poty river floods through the sump, as a future dam Castle of PiauÃ, or from use of urban detention basins, locks tide and pumping system of rainwater in interconnected basins with the Poty River.
18

Konstrukce čtyřkolky (ATV) s elektrickým pohonem / Design of all-terrain vehicle with electric drive

Kučera, Pavel January 2011 (has links)
This master's thesis describes the design of All-Terrain Vehicle (ATV) with electric drive. The design is focused on the main parts of the ATV, which are designed with modern trends ATVs. Location of electric drive and batteries in the frame of the ATV is solved for the sport version of the ATV. Steering geometry is designed using the program Adams. For models of main components are created stress analysis in Ansys Workbench. The input is 3D model, which is created in Pro/Engineer. The braking system and wheels are designed for movement and braking of the terrain.
19

Estudo de viabilidade técnica sobre o uso de ligas de alumínio na fabricação de eixos traseiros trativos para aplicação em veículos comerciais

Saito, Kyosuke Siqueira 15 February 2013 (has links)
Made available in DSpace on 2016-03-15T19:36:37Z (GMT). No. of bitstreams: 1 Kyosuke Siqueira Saito.pdf: 4273063 bytes, checksum: 72ef7d0c147daede5763573276e7efda (MD5) Previous issue date: 2013-02-15 / Universidade Presbiteriana Mackenzie / The development of new commercial vehicles have as one of its major goals increase the operational energetic efficiency or fuel consumption decrease. The vehicle´s mass reduction is one of the most direct ways to achieve this goal. The vehicle´s axles usually have its structure made of ferrous materials due to its high strength and low cost. Alternative materials with lower density and higher strength are continuosly researched and developed. Among these materials the aluminum compared with ferrous materials appears as an interesting alternative to replace ferrous alloys in some applications. The aluminum have its density significantly smaller than ferrous materials opening possibilities to significant mass reductions. In this study were performed an evaluation through the comparison of aluminum alloys and ferrous materials on different load conditions and were presented the replacement gains for each load situation. It was evaluated possibility to replace ferrous materials with aluminum alloys on commercial vehicles rear axle structures through finite element analysis as a step on a new product validation. The study results show that is possible to use the aluminum in commercial vehicle axles with mass reduction ranging from 1,1% to 61,0% without loss of structural properties. / O desenvolvimento de novos veículos comerciais tem como um de seus objetivos principais o aumento da eficiência energética operacional ou redução do consumo de combustível. A redução da massa dos veículos é uma das estratégias mais diretas para o alcance deste objetivo. Os eixos de veículos tradicionalmente têm sua estrutura feita de materiais ferrosos devido à sua alta resistência e baixo custo. Materiais alternativos de mais baixa densidade e alta resistência são pesquisados e desenvolvidos continuamente. Dentre esses materiais, o alumínio, comparado com materiais ferrosos tem-se mostrado uma alternativa interessante para a substituição de ligas ferrosas para algumas aplicações. O alumínio possui uma densidade muito inferior a dos ferrosos abrindo a possibilidade de ganhos significativos de massa. Neste estudo foi feito uma avaliação através da comparação entre ligas de alumínio e materiais ferrosos em diferentes condições de carregamento e apresentado os ganhos da substituição em cada condição de carregamento. Foi avaliada a possibilidade de substituir materiais ferrosos por ligas de alumínio na estrutura de eixos traseiros de veículos comerciais através de uma análise por elementos finitos como uma etapa da validação de um novo produto. Os resultados do estudo mostram que é possível usar o alumínio na estrutura de eixos de veículos comerciais com redução de massa variando de 1,1% a 61,0% sem perda de características estruturais.
20

Festigkeitsberechnung von Wellen und Achsen unter dem Einfluss von Größe, Kerbschärfe und Maximallast

Bretschneider, David 19 July 2023 (has links)
Wellen und Achsen im Bereich der Antriebstechnik erfahren in den überwiegenden Anwendungen zyklische Beanspruchungen. Folglich ist für die Festigkeitsberechnung im Nennspannungskonzept eine möglichst exakte Kenntnis der Bauteilwöhlerlinie von zentraler Bedeutung. Halbzeug-Größe, Spannungsformzahl und die statischen Maximallasten beeinflussen neben weiteren Faktoren die Charakteristik der Wöhlerlinie bzw. die Dauerfestigkeit. Im Zusammenhang mit der Weiterentwicklung der Norm DIN 743 gilt diesen Größen der Fokus. Die vorliegende Arbeit betrachtet die Abschätzung der Zug-Druck-Wechselfestigkeit basierend auf dem technologischen Größeneinflussfaktor sowie der Makrohärte und deren Übertragbarkeit auf große Bauteildimensionen. In dem Zusammenhang wird der technologische Größeneinflussfaktor für Durchmesser bis 700 mm anhand einer numerisch-analytischen Simulation ermittelt und zudem mit Härtemessungen validiert. Ferner wird auf Grundlage von Treppenstufenversuchen die Abschätzung der Zug-Druck-Wechselfestigkeit aus der Härte für große Halbzeugdimensionen betrachtet. Neben dem technologischen Größeneinflussfaktor abhängig von der Härtbarkeit liegen als Ergebnisse Zusammenhänge zur Abschätzung der Zug-Druck-Wechselfestigkeit aus der Härte für große Halbzeuge vor. Darüber hinaus wird mit experimentellen Untersuchungen die Wöhlerlinie im Zeitfestigkeitsbereich analysiert. Basierend darauf werden der Wöhlerexponent sowie die Knick-Schwingspielzahl zur Dauerdauerfestigkeit in Abhängigkeit von der Formzahl abgeleitet. Abschließend widmet sich die Arbeit den Auswirkungen von statischen Maximallasten auf die Dauerfestigkeit. Dazu werden die lokalen elastisch-plastischen Beanspruchungen infolge von Maximallasten mit dem Örtlichen Konzept erfasst und in Treppenstufenversuchen die Dauerfestigkeit mit zusätzlicher Maximallast betrachtet. Ausgehend davon wird ein Konzept zur Abschätzung der lokalen Beanspruchungen sowie der lokalen Dauerfestigkeit bei Berücksichtigung des Einflusses der Maximallasten vorgestellt. / Shafts and axles of drive systems are stressed by cyclic loads in most applications. Therefore, an accurate calculation of the S-N-curve is fundamental for the system’s strength assessment based on nominal stresses. Component size, the stress concentration factor, and static loads influence the behavior of the S-N-curve and the fatigue strength, among others. In the context of a further development of the standard DIN 743, the scope is these values. This thesis focuses on the estimation of the fatigue strength for tension/compression based on the technological size factor as well as the macro hardness and their transferability to larger component sizes. In this context the technological size factor is determined by a numeric-analytical simulation for diameters up to 700 mm and is also validated with hardness measurements. Furthermore, the estimation of the fatigue strength for larger component sizes based on the hardness is supported by fatigue tests. In addition to the technological size factor depending on the hardenability, the results are obtained by an estimation approach for large components between the fatigue strength for tension/compression and the hardness. In the next step, the S-N-curve is analyzed with experimental investigations for the finite life area. Based on this, the slope of the S-N-curve (“Woehler slope”) and the knee point for the endurance limit depending on the stress concentration factor are determined. Finally, the thesis deals with the impact of static loads on fatigue strength. For this purpose, the local elastic-plastic stress-strain behavior due to static loads is calculated with the strain life assessment (local concept) and the fatigue strength influenced by static loads is analyzed as well. Based on this, an approach for the estimation of local stress-strain behavior and for the fatigue strength considering the static loads are proposed.

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