Eficiência energética de um trator agrícola 4x2 TDA em pista de concreto em função do desgaste dos pneus e da velocidade de deslocamento

Abstract

The agricultural expansion is increasing and the agricultural tractor is the main source of power used in the conduction of the crops. Agricultural tires are among the main components of agricultural machinery, having great importance in operating costs. Seeking to know the effectiveness of agricultural tires in the mechanized operation, this study was carried out with the objective of evaluating the energy efficiency of a 4x2 FWD tractor in the function of the displacement speed, using new and worn tires on a concrete runway. The work was conducted in the experimental area of the Agricultural Accident Investigation Laboratory – LIMA, belonging to the Federal University of Ceará, on a concrete floor, using a tractor 4x2 FWD Valtra BM120 with power 88.26 kW (120 cv), without any type of liquid or solid ballast, in train system for the tests, the track and the tractor followed the OECD-Code 2 standards. We used two sets of tires, new and worn. Evaluated the hourly consumption (CH) and specific (EC) of fuel, power (PB) and income on the drawbar (RB), traction coefficient (TC) and slipping. The data were acquired with the aid of sensors installed throughout the tractor and stored in a datalloger. The design was a completely randomized design (DIC), in a 5x2 factorial scheme, with five displacement speeds (1,11; 1,39; 1,67; 2,36 e 2,78 m.s-1) and two types of tire sets (new and worn) with five replicates, followed by analysis of variance and test of means. There was significant interaction for hourly and specific consumption, being that the wear of the tire did not interfere in the CH and the EC, for the different displacement speeds, CH did not differ statistically. The speed of 2.36 m.s-1 obtained the lowest CE. PB, RB and TC increased with increasing forward speed, being the speed of 2.87 m.s-1 and the new tire, which obtained the highest values. The slipping increased with increasing speeds being those which were within acceptable limits were 2.36 and 2.78 m.s-1. Worn tires have slipping below the recommended one, being within range. Only the set of new tires. It is concluded that the new tire sets are more recommended to be used, adopting the higher displacement speeds, preferentially those of 2.36 and 2.78 m.s-1.