The thesis deals with the breeding of cattle, especially the issue of distribution of feed, which is technologically solved in many variants. The second part is devoted to the selection of two mixing wagons of different constructions, their characteristics and description of the method of handling the feeds. The monitored data was then evaluated and processed into tables and graphs. Finally, the two different mixed feed wagons were compared and evaluated in terms of accuracy of loading and economy.

Orientador: Paulo Roberto Mei / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-16T10:24:52Z (GMT). No. of bitstreams: 1 VillasBoas_RenatoLyra_M.pdf: 13424471 bytes, checksum: c7a6d60275922ab9255b8f8e74fd29e1 (MD5) Previous issue date: 2010 / Resumo: Neste trabalho foi desenvolvido um aço microligado com 0,7% de carbono para fabricação de rodas ferroviárias. Tomou-se como base um aço classe C da norma AAR M-107 e adicionou-se nióbio e molibdênio. A pesquisa foi realizada em duas etapas distintas. A primeira etapa estudou-se o efeito da adição de nióbio e molibdênio no aço com 0,7% de carbono antes e após a deformação por laminação, simulando o forjamento real das rodas ferroviárias produzidas na MWL Brasil. Com os dados disponíveis passou-se à segunda etapa da pesquisa onde foram fabricadas e ensaiadas rodas ferroviárias na MWL Brasil usando um aço com composição química semelhante à utilizada na primeira etapa para observar o efeito do nióbio e molibdênio nas mesmas. Os aços foram austenitizados a 1250 °C para solubilização do nióbio na austenita e deformados a partir de 1200 °C. Na primeira etapa o aço foi laminado em 4 passes sofrendo uma deformação total na espessura de 67% e resfriado ao ar. Na segunda etapa, o aço foi forjado pelo processo de fabricação usado pela MWL Brasil. Após o tratamento térmico, foram realizados ensaios de dureza da perlita, tração, impacto, tenacidade à fratura, além de microscopia ótica e medida do tamanho de grão austenítico. Observou-se aumento no limite de escoamento (8,5%), ductilidade (15%), energia de impacto (29%), tenacidade à fratura (33%) e temperabilidade pela microadição de nióbio e molibdênio, mostrando que esses elementos podem melhorar o desempenho das rodas ferroviárias atualmente produzidas. / Abstract: In this work it was developed a microalloyed steel with 0.7% carbon to manufacture railway wheels. It was taken as basis a steel class C of standard AAR M-107 and added niobium and molybdenum. The research was conducted in two stages. The first step was studied the effect of the addition of niobium and molybdenum on 0.7% C steel before and after deformation by rolling, simulating the actual forging of railroad wheels process in MWL Brasil. With the available data the second stage of the research was conducted, manufacturing and testing railway wheels in MWL Brasil, using a steel with similar chemical composition to that was used in the first step to observe the effect of niobium and molybdenum in them. The steels were austenitized at 1250 °C for niobium solubilization in austenite and deformed from 1200 °C. In the first stage, the steels were rolled at 4 passes undergoing a total deformation of 67% in thickness and aircooled. In the second step, the steels were forged by MWL Brasil manufacturing process. After heat treatment, tests on pearlite hardness, tensile, impact, fracture toughness were performed. Microstructure was observed by optical microscopy and the austenite grain size was measured. It was observed an increasing on the yield strength (8,5%), ductility (15%), impact energy (29%), fracture toughness (33%) and hardenability by niobium and molybdenum microalloying, showing that these elements can improve the performance of railway wheels nowadays produced by MWL Brasil. / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica

This thesis deals with an approach to monitor the integrity and composition of cargo wagons withthe help of Wireless Sensor Network (WSN). The WSN is to be fully automated that does notneed any human intervention for gathering information about the composition and integrity ofcargo trains, which are the most necessary factors for Cargo Logistics. The nodes are deployed inevery wagon along with the master node in the main locomotive. The master node in thelocomotive gets the information from the slave nodes placed in the cargo wagons in successivesessions. If there are any unexpected changes in the composition of the wagon, theacknowledgments to the locomotive will be terminated. This approach mainly focuses ondesigning energy-efficient as well as cost-efficient WSN. The designed WSN can accommodateto changes, which are caused by external conditions. The designed approach is also scalable. TheWSN is designed with the usage of Zigbee mesh protocol with Arduino Microcontroller as thebrain of the system that is validated and verified in the indoor, imitating the railway environment.

The link suspension is the most prevailing suspension system for freight wagons in central and western Europe. The system design is simple and has existed for more than 100 years. However, still its characteristics are not fully understood. This thesis emphasizes freight wagon dynamics and comprises three parts: In the first part a review of freight wagon running gear is made. The different suspension systems are described and their advantages and disadvantages are discussed. The review covers the running gear standardized by UIC and the conventional so-called three-piece bogie. Additionally five improved three-piece bogies and twelve novel running gear designs are presented. The second part focuses on the lateral force-displacement characteristics in the link suspension. Results from stationary measurements on freight wagons and laboratory tests of the link suspension characteristics are presented. To improve understanding of the various mechanisms and phenomena in link suspension systems a simulation model is developed. Link suspension systems have strongly nonlinear characteristics including a hysteresis loop. The loop exhibits usually three characteristic sections with different tangential stiffnesses. The actual contact geometry of the links and end bearings has a significant influence on the characteristics. By wear in ordinary service - as well as by geometric tolerances on new components - the contact geometry may deviate considerably from nominal geometry. Further, it seems that elastic deformation in the contact surfaces has considerable effects on the suspension characteristics, in particular on the initial rolling stiffness for small displacements. Also, flexibilities in links and end bearings influence the characteristics. It is also observed that new components after a short period of dynamic testing can exhibit a very low amount of energy dissipation, a phenomenon that is also indicated in some stationary measurements on wagons. To summarize the second part, it appears that the link suspension characteristics are very sensitive to several factors being hard to control in the real world of freight wagon operations. The various stiffnesses and hysteresis loops have a considerable variation and may have a strong influence on the ride qualities of vehicles. As long as the characteristics can not be controlled within closer limits than found in this study, there is a strong need for sensitivity analysis to be made, both in predictive multibody simulations of vehicle dynamics, as well as in verification and acceptance tests. In the third part a study on the possibility to improve ride qualities of freight wagons with link suspensions is presented. Parametric studies with multibody dynamic simulations on freight wagons equipped with link-suspension bogies are performed. The effect of supplementary friction and hydraulic damping is investigated under various running conditions: speed, loading, tangent and curved track, wheel-rail contact geometry, track gauge and track irregularities. Substantial improvements of the lateral running behaviour of wagons with link suspension bogies can be achieved - both at ordinary speeds and at increased speeds - by using a proper combination of supplementary hydraulic dampers. Speeds up to 160 km/h could be realistic.

This thesis deals with analysis of constructional solution of large-loading wagons used nowadays. In the first part of this thesis is my own construction design of large-loading wagon, furthermore there is a design of screw conveyor. In the following part stress strain analysis of the chassis of large-loading wagon was made using the finite element method. On the basis of these results were suggested modifications of the chassis. Finally the stress strain analysis of the adapted chassis was made. Attachments of the thesis include deformation results of the chassis and design documentation of the large-loading wagon. This thesis was created in cooperation with ZDT spol. s.r.o. Nové Veselí.

The diploma thesis entitled The effect of individual components of mixed feed rations in the mixer feeder wagon (without a cutter) on the accuracy of loading is divided into two separate parts. In the first (theoretical) part, the issue of livestock together with preparation and distribution of feed with the mixing feeder wagons are analyzed. The second (practical) part of my work is focused on specific selection of a mixing feeder truck, diet components characteristic and way of their loading including evaluation of their loading accuracy. The main objective of the thesis is to specify evaluation of loading accuracy of each component in the mixed feed rations of a mixing feeder wagon in the selected agricultural companies that specialize in milk and meat production.

The diploma thesis deals with the accuracy of loading individual components of mixed feed dose into a self-propelled mixing feed wagon using a milling cutter. The theoretical part of the thesis defines the mixed feed used for cattle breeding, then the selected world leading producers of self-propelled mixing feed wagons are listed and finally the current technological trends and innovations in this field. The practical part is firstly focused on selecting a particular company equipped with a self-propelled mixing wagon with a programmable weight calculator and a computer program. Secondly, the characteristics of feed rations and the average dairy production of dairy groups in the selected holding is mentioned. The main aim is to compare the ratio of the actually loaded weights with the required weights in the individual feed ration components for the groups of production dairy cows.

The theoretical part features an overview of the historical development of dairy cows feeding and introduces currently used trends in feeding. This part also outlines basic technologies in the production of roughage and describes modern feed distribution machinery. The practical part evaluates the accuracy of loading of individual components and the total weight of a feed ration loaded into a vertical suspension mixer feeder wagon by a front-end loader tractor. The observation was carried out at Mr. Kadlec's family farm in Velký Bor near Netolice and lasted four months. During this period, the actual weight of loaded components (grass-clover haylage, maize silage, grains meal) was being monitored daily. The evaluation came to a conclusion that grass-clover haylage stored in bales is loaded with a greater accuracy than maize silage stored in a clamp silo.

Orientador: Itamar Ferreira / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-20T17:14:11Z (GMT). No. of bitstreams: 1 Queiroz_SymeReginaSouza_D.pdf: 5101982 bytes, checksum: 1143c4b43c52ed713ed719367ce07ead (MD5) Previous issue date: 2012 / Resumo: A tendência mundial das estradas de ferro é utilizar carga elevada por vagão no transporte de produtos e alta velocidade no setor de passageiros. Em ambas as situações, as rodas ferroviárias são muito solicitadas mecanicamente e, em função disso, as propriedades mecânicas dessas rodas devem ser rigorosamente controladas, tendo em vista que as principais causas de acidentes envolvendo trincas nas rodas, ou a retirada da roda antes do final de sua vida, estão direta ou indiretamente associadas a baixos níveis de resistência mecânica, resistência à fadiga e tenacidade à fratura. O conhecimento do comportamento mecânico das rodas ferroviárias com base nas suas propriedades mecânicas é imprescindível para o projeto de rodas ferroviárias e para o aprimoramento de seu processo de fabricação. Este trabalho tem como objetivo caracterizar e analisar a microestrutura, as propriedades mecânicas e os micromecanismos de fratura de cinco rodas ferroviárias, duas fundidas e três forjadas, a partir de corpos-de-prova usinados dos aros e discos dessas rodas. As propriedades mecânicas analisadas são as básicas (limite de escoamento, limite de resistência à tração, alongamento específico até à fratura, redução de área, dureza e energia de impacto Charpy), a resistência à fadiga e a tenacidade à fratura, de corpos-de-prova usinados das rodas ferroviárias. Além das microestruturas e das propriedades mecânicas, foram também caracterizados e analisados os micromecanismos de fratura dos corpos-de-prova dos ensaios de fadiga e impacto, por meio de microscopia eletrônica de varredura. Os resultados dos ensaios indicam, em relação aos limites de escoamento e de resistência à tração, que não houve diferenças significativas entre as rodas fundidas e forjadas analisadas. Quanto à dureza (HRC), ductilidade (alongamento específico e redução de área) e tenacidade à fratura, as rodas forjadas apresentaram valores superiores. Em relação à resistência à fadiga, uma propriedade importante no caso de rodas ferroviárias, os corpos-de-prova usinados das rodas forjadas apresentaram melhores resultados em relação às rodas fundidas. Pode-se também concluir que, tanto para as propriedades mecânicas básicas e nobres como também para os micromecanismos de fratura, os resultados obtidos são compatíveis aos encontrados na literatura especializada, validando e comprovando que a metodologia de análise pode ser utilizada para melhorar os projetos e os processos de fabricação de rodas ferroviárias de aço fundidas e forjadas / Abstract: The word wide tendency of railroads is to use high load per wagon in cargo transport and high-speed in passenger sector. In both situations, the railway wheels are very mechanically requered, and as a result, the mechanical properties of these wheels should be controlled strictly in order that the main causes of accidents involving wheels cracks, or withdrawal of the wheel before end of its life, are directly or indirectly associated with low levels of strength, fatigue resistance and fracture toughness. Knowledge of the mechanical behavior of railway wheels based on their mechanical properties is essential for the design of railway wheels and the improvement of its manufacturing process. This work aims to characterize and analyze the microstructure, mechanical properties and fracture micromechanisms of five railway wheels, two cast and three forged, from the machined specimens of the rim and web of these wheels. The analyzed mechanical properties are the basics (yield strength, tensile strength, elongation, reduction in area, hardness and Charpy impact energy) the fatigue resistance and the fracture toughness, from the specimens machined of railway wheels. In addition to the microstructures and mechanical properties were characterized and analyzed the micromechanisms of fracture of the specimens of fatigue and impact tests, using scanning electron microscopy. The test results indicate, with respect to the yield strength and tensile strength, there were no significant differences between cast and forged wheels analyzed. The hardness (HRC), ductility (elongation and reduction in area) and fracture toughness of the forged wheels showed higher values. Regarding resistance to fatigue, an important property in the case of railway wheels, the forged wheels machined specimens shown better results compared to cast wheels. One can also conclude that, for both the basic and noble mechanical properties as well as for the micromechanisms of fracture, the results are compatible with those found in the literature, validating and verifying that the method of analysis can be used to improve the castings and forgings steel railway wheels and manufacturing processes and projects / Doutorado / Materiais e Processos de Fabricação / Doutora em Engenharia Mecânica

The subject of this work is the proposal of a technological process to create a train car bumper using volume thermoforming. The S235JR (11375) steel has been chosen as the main material. The work contains technological calculations, blueprint documentation of the mold, of the tool and a proposal of the set of machines for the production line. The capacity of such production line has been calculated to be 12460 pieces per year. Economical-technological evaluation of the production is also included.