Demanda de tração e energética de uma semeadora adubadora com variação de profundidade da haste sulcadora em solo argiloso

Abstract

The objective of this work was to analyze the power demand of a fertilizer sowing machine operating in no-till on clay soil in the city of Sinop-MT. The depth of the furrow rods for fertilizer deposition (12 to 20 cm) and the working speed (5 and 7 km h-1) were varied. Six repetitions were performed with four depths and one without stem (seed only), thus obtaining 60 experimental units. The main response variables evaluated were traction force, power required in the engine and fuel consumption. The power demand with the highest observed value was through the torque method, where 16.3 hp was obtained per sowing unit with rods 20 cm deep and operating at 7 km h-1 . When analyzing the power demand without the stems (seed only), there was a drop to 6.8 hp per unit at the same speed. From an energetic point of view, it is more efficient to operate at the highest speed used (7 km h-1 ). Using only seed, the operational consumption was 6.1 L ha-1 . Using the rods at 20 cm and 7 km h-1 , 10.9 L ha- 1, 323 g kWh-1 of specific consumption and 2.61 kWh L-1 of specific energy were obtained. The greatest energy demand was operating at 5 km h-1 at a depth of 20 cm, where operational consumption of 12.6 L ha-1 was obtained. The recommended power range for dimensioning in clayey soils with a flat topography is 0.73 to 0.81 hp cm-1 of the stem depth. For speeds greater than 7 km h-1 , it is recommended to consider in the predictive calculations, specific traction force between 18.5 and 20 kgf cm-1 of stem depth for each seeding unit.