Análise do desgaste de um motor de trator agrícola submetido a amaciamento em dinamômetro

Abstract

Agricultural mechanization is an important pillar of growth and prosperity in the primary sector in Brazil, as it maximizes production and field operation efficiency. To further maximize gains from the activity and reduce operational costs, the tools used, and maintenance and operation techniques are improved. The running-in of agricultural engines is crucial for better performance during the equipment's lifespan and is typically carried out in the field for approximately 100 machine-hours, or on dynamometers, which reduce this time to 10 machine-hours. Thus, this study aims to analyze the wear of an agricultural tractor engine subjected to running-in on a dynamometer, imposing controlled loads. It was proposed to analyze lubricating oil samples from an agricultural tractor model run-in on a dynamometer over the running-in period, with collections made at intervals of 0, 2, 4, 6, 8, and 10 machine-hours. The samples were subjected to plasma optical emission spectrometry to detect concentrations of Iron (Fe) from the cylinders, crankshaft, rings, pistons, and Copper (Cu) from bearings and bushes. Additionally, lubricating oil consumption was analyzed by weighing the oil, and the increase in engine power was analyzed through dynamometry. It was found that after the running-in period on the dynamometer, the iron concentration increased by 23.87%, and copper showed an increase of 36.19% from the control sample. Moreover, the power showed an increase of 13.95%, and the specific fuel consumption experienced a reduction of 9.8%. The results were compared with values established in the literature, and it was found that the concentrations of wear metals comply with the limits for the elements, eliminating the need for an oil change at the end of the break-in period for the tested tractor.