Otávio Dias da Costa Machado

Análise comparativa do peso específico dos tratores agrícolas fabricados no Brasil e seus efeitos sobre a seleção e uso

The aptitude and performance of the agricultural tractors on field conditions have been influenced by the tractor weight. This parameter has varied mainly according to the manufacturers, generating a demand of comparative information. The objective of this research was to analyze the weight of Brazilian agricultural tractors, aiding in the selection and in its appropriate use. The present research included 103 models of commercial tractors of the brands Massey Ferguson, Agrale, New Holland, John Deere, Ursus and Valtra. Tractor weight and weight/power relationship, separately in different brands, traction type and power groups, were analyzed. The data were analyzed through the t test (Student). Significant differences were observed for the brands and power groups when the weight/power relationship was considered. The parameter weight has differed also for the traction type. Besides, the weight/power relationship without ballast weight has decreased with the increase of power. Therefore, Brazilian agricultural wheeled tractors are heterogeneous regarding weight and weight/power, what influences their economic performance. These parameters must be considered during the use and choice of a tractor.

Índice de mecanização de propriedades orizícolas no Rio Grande do Sul, Brasil

Characterized as activity of high economic expression in Rio Grande do Sul, the rice production is practiced in an intense way, above all in the applied mechanization. Tends as objective to diagnose the mechanization level (kW/ha), in function of the agricultural area used with rice (AARR) and of the total agricultural area (AAGT), a sample of 87 properties, that its amoung their activities develop the rice production, was analyzed. For the representation of the scale of the properties in the studied index, they were applied 8 strata in function of the area agricultural total of the same ones, being considered for the available potency the agricultural tractors in activity and the declared productive areas. The differentiated participation of the area of cultivation of rice in the different strata carted in expressive differences of the mechanization index, when analyzed the area of rice and the total agricultural area. The bedding was shown efficient in the determination of the variation of the mechanization index along the studied strata, just happening significant difference between the strata 3 (31 a 45 ha) and 4 (46 a 90 ha) and the strata 6 (131 a 180 ha) and 7 (181 a 400 ha), when related the index studied to the area of rice, being represented by intervals of class indeed differentiated for the other averages.