ADDITION OF FUEL GASES TO CONVENTIONAL PROTECTION ATMOSPHERES IN THE MIG-MAG PROCESS

摘要

The present invention consists of gaseous formulations containing conventional protective gases and combustible (reducing) gases for welding carbon steels by the mig-mag process. This technology is intended for application in the metal fabrication industries. The protective gaseous formulations, object of the present patent, were developed from the main conventional mixtures currently in use by the industry, consisting of argon (air) and carbon dioxide (co2) gases such as: air + 12% co2; air + 25% CO2 and pure CO2. To these were added proportions of combustible or reducing gases (hydrogen, propylene, acetylene, natural gas, propane, butane, among others). The percentage of fuel gases mentioned above in conventional mixtures (air + 12% co2; air + 25% co2 and pure co2) may vary from 0.5 to 6.0%. In these mixtures, air gas has a protective effect and is inert; CO2 has an oxidizing and protective effect; while fuel gas has protective and reducing effect.