Influência do lastro líquido e da pressão interna dos pneus na relação cinemática de um trator.

Abstract

A major source of power and work in rural areas is the agricultural tractor. The proper use and tires, both its constructive type and its internal pressure are factors that significantly affect their performance, and other factors such as ballasting and forward speed change their traction capacity. This study aims to evaluate the kinematics relationship of a 4x2 tractor equipped with front wheel assist (FWA), varying the internal pressure of the tires on three conditions (24 psi, 18 psi and 12 psi) and the amount of liquid ballast in three levels (75%, 50% and 25% of the internal volume of the tire filled with water). The tests were performed on the asphalt track in order to standardize all tests. Once collected and analyzed, the following results were found: the internal pressure and ballast distribution exerted significant influence on the cinematic relationship, showing downward trend when the internal pressure and ballast were also diminished. The interaction between these two factors also significantly alter the kinematics relationship, presenting the best condition for the situation of 75% of liquid ballast in the front and rear tires, with internal pressure of 18 psi, with a value of 1.0018, and the worst condition setting up 50% of liquid ballast in the front and rear tires and internal pressure of 12 psi, with a value of 0.9924.