Evaluation of the Effect of Co and Co2 Gases Generation on Short-Circuit Metal Transfer in the Mig/Mag Welding Process

Abstract

Several works have shown the influence of parameters and shielding gases on the generation of fumes in MIG/MAG welding, but little has been shown on the emission of toxic and asphyxiating gases. This work aims to evaluate the effect of shielding gas composition on gas emission levels in MIG/MAG welding, using pure CO2 and mixtures of Argon with CO2, maintaining the same average current. It was found that the values of CO2 generation in the data acquired in tests with 100%CO2 shielding gas varied with limits above those allowed by NR-15 and OSHA. The data referring to the generation of CO2 during tests with Ar+25%CO2 did not exceed these limits. For CO generation, tests with a voltage of 19V did not exceed the limits of NR-15 and OSHA, for both shielding gases, with the exception of voltages of 21V and 23V.