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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352

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    Mechanical harvesting of coffee in high slope
    (Universidade Federal Rural do Semi-Árido, 2016) Santinato, Felipe; Silva, Rrouverson Pereira da; Silva, Vantuir de Albuquerque; Silva, Carlos Diego da; Tavares, Tiago de Oliveira
    Brazilian coffee farming is carried out both on flat and steep lands. In flat areas, mechanized operations are intensive; however, in steep slope areas, certain mechanized operations cannot be performed, such as harvesting. Based on this, the industry has developed machinery to harvest coffee in areas with up to 30% slope. However, harvesters have their efficiency and operational performance influenced by land slope. Thus, this study aimed to evaluate the operational performance and harvesting efficiency of a steep-slope harvester under different situations, using different speed settings. The experiment was carried out in the county of Santo Antônio do Amparo, state of Minas Gerais, Brazil, using five coffee stands with 10, 15, 20, 25 and 30% slope. Evaluations were performed with a self-propelled harvester (Electron, TDI®, Araguari, MG, Brazil) at three rotation speeds (600, 800 and 1.000 rpm) and two ground speeds (800 and 1.000 m h-1). The results showed the lower speed (800 m h-1) was suitable for 10% slope areas since the amount of fallen coffee berries. For areas of 20% slope, harvesting time was 21.6% longer than in flatter areas. Downtime varied from 10.66 to 29.18% total harvest due to a higher number of maneuvers.
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    Performance of a special tractor as a function of ballasting and front-wheel drive in coffee harvesting
    (Editora UFLA, 2018-01) Tavares, Tiago de Oliveira; Borba, Matheus Anaan de Paula; Gallo, Luís Alexandre Michelli; Gírio, Lucas Augusto da Silva; Paixão, Carla Segatto Strini; Silva, Rouverson Pereira da
    One of the main concerns before agricultural mechanization is the fuel cost from an economic and environmental point of view. In some literature, it has been demonstrated that the adequacy of tractors is directly related to consumption, which may become a strategy to reduce it. However, the studies were performed with conventional tractors, without information on how the special coffee tractors behave to the adequacy. In this respect, the aim of the present study was to evaluate the hourly fuel consumption in six possible adjustments of a special tractor in the operation of mechanized coffee harvesting. A 4x2 FWD tractor was used, with 52.2 kW power and 2400 kg mass, with 40% to the front axle and 60% to the rear to pull a Master Café 2 coffee harvester with 2900 kg mass without load. The treatments consisted of three ballast configurations in the tractor whether or not using auxiliary front-wheel drive (FWD). The adopted mass-power ratios were: 48, 52 and 56 kg kW-1 ; obtained through the quantitative alteration of liquid and solid ballasts of the tractor, respecting the mass distribution between the axles recommended by the tractor manufacturer. The evaluations consisted of monitoring fuel consumption at regular hourly intervals, following the premises of statistical process control. It is concluded that the mass-power ratio of 56 kg kW-1 with driven FWD should be used in order to obtain lower slipping, lower average hourly fuel consumption and higher quality.
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    Qualidade do recolhimento mecanizado do café
    (Editora UFLA, 2015-10) Tavares, Tiago de Oliveira; Santinato, Felipe; Silva, Rouverson Pereira da; Voltarelli, Murilo Aparecido; Paixão, Carla Segatto Strini; Santinato, Roberto
    O recolhimento do café de varrição é essencial para reduzir as perdas que ocorreram de forma natural ou devido à colheita. Objetivou-se avaliar a qualidade operacional de um conjunto mecanizado de recolhimento de café, utilizando o controle estatístico de processo. A avaliação da qualidade operacional foi materializada em grade amostral de 27 pontos, espaçados em 10 m na fileira do cafeeiro. A operação foi realizada em lavoura com carga pendente de 90,0 sacas de café ben. ha -1 , sendo 15,3 sacas de café ben. ha -1 , presentes no solo. Utilizou-se como tratamentos três rotações da TDP (444, 540 e 630 rpm), casualizadas estatisticamente, com nove repetições. Avaliou-se a composição do material inicial presente no solo, a quantidade de café remanescente após a operação da recolhedora, a eficiência de recolhimento e a eficiência de separação do café e detritos no interior da máquina. Concluiu-se que a quantidade de material a ser recolhido pode apresentar alta variabilidade na distribuição. A quantidade de café presente neste material apresenta alta variabilidade, interferindo na capacidade de recolhimento e separação da máquina. O incremento na rotação da TDP da recolhedora não eleva a eficiência de recolhimento, mas melhora a eficiência de separação do café no interior da máquina.