Estudo da aplicação de revestimento duro por soldagem com arames tubulares quanto à resistência ao desgaste de facas picadoras de cana-de-açúcar

Abstract

The brazilian alcohol and sugar industrie were presented the large growth in the last years. However, the maintenance of industries presented high cost because the wear of equipments.This work aims to study hardfacings application by Flux Cored Arc Welding on wear resistance to the sugar-cane choping knives. It also seeks verify wether the Rubber Wheel Test is effective or not to simulate the wear that occurs with this tool type. Three tubular wires FeCrC alloy were used, the which ones differ to each other by the different contents of C, Cr, Si and Mn. Besides ones differ to each other by the addition of Nb in second and Ti and Mo in the third. One shielded electrode of recognized efficiency was used for comparison with the tubular wires performance. Metal transfer modes was study to select a parameters set with the tubular wires in the short-circuit region by use the same welding current. Samples were made for the wear evaluation in laboratory with Rubber Wheel Test. Afterwards, they were fabricate sugar-cane choping knives, hardfacing welded with same weldings parameters and set up in choping equipment of an alcohol distillery. The wear evaluation were done by weight loss. The contend Nb wire presented the biggest wear resistance in laboratory and due to the crack presence and to fracture of the hardfacing, presented the minor wear resistance in industrie. The FeCrC wire and the contend Ti and Mo wire presented similar wear resistance with the worse performance in laboratory and the best performance in industrie. Compared to the shielded electrode, only the contend Nb wire presented similar performance in laboratory and the FeCrC wire and the wire with adition of Ti and Mo, presented similar performance in industrie. The industrie wear test was less severe who in laboratory and the Rubber Wheel Test wasn't effective to represent the sugarcane choping knives wear, because not simulating the impact occurrence.