Influence of Extra Weight and Tire Pressure on Fuel Consumption at Normal Tractor Slippage

Tire pressure and wheel load are both easily managed parameters which play a significant role in tillage operations for limiting slip which involves energy loss. To a great extent, this aspect affects the fuel consumption and the time required for soil tillage. The study was focused on the tire pressure and extra weight variation effect on fuel consumption and work productivity for soil tillage at normal tractor wheels slippage (7-15%). The experimental research unit composed of an 82.3 kW 4WD tractor and a reversible 4-bodies plough is presented. Tests were carried out on a stubble loam, where slip of tractor driving wheels was < 15%, tractor front ballast mass was varied in the range from 0 to 520 kg and inflation pressure in the tires from 240 kPa to 100 kPa. Dependences of tractor performance indicators on ballast mass and tires inflation pressure are presented. When tractor tire slip varies in the range from 7 to 15 percent (which is normal slip in the soil), reducing the tires inflation pressure decreases the driving wheel slip and fuel consumption, while increases work productivity. Increasing the additional mass of the tractor (adding ballast weights) decreases the driving wheel slip, increases work productivity, but also increases fuel consumption and soil compaction.