Determinação dos parâmetros de soldagem mais adequados para união de tubos de parede fina pelo processo de eletrodo revestido

Abstract

This work refers to an empirical determination of best SMAW welding parameters for pipes made of SAE-AISI 4130 steel, with thin wall (1,25 mm) and 19,05 mm diameter to be used by the mini-baja team of Federal University of Uberlandia. All welding tests were made manually with the intention to demonstrate the advantages and limitations for a future application by students of the mini-baja team. It was concluded that the more suitable electrode would be the rutile electrode of the E308 type (for stainless steel), because it is easier to weld and it offers a better weld bead finishing. The welding current adjustment for the 2,5 mm electrode should be around 60 A. Thus, the more recommended process to be used during a competition would be the SMAW because the power source and electrodes are easy to be transported and due to the fact that it offers a better protection of the active zone against winds. The tests performed showed that a trained student can indeed perform a welding with acceptable quality by using rutile electrode of the E308 type of 2,5 mm diameter. It is recommended to use an inverter-type power source that provides direct current and not a welding transformer, since alternating current impairs process stability.