Utilização de gás de purga no processo de soldagem TIG em aço inoxidável austenítico ABNT 304

Abstract

The food industry requires a high level of safety against food contamination. Thus, machinery and equipment used for processing must not contain material that, in contact with food, releases substances that are not part of the process, which could harm the consumer’s health. To avoid some forms of contamination, the construction of machinery follows specific standards for choosing the material that will come into contact with food. One of the most suitable materials for this use is stainless steel, due to its characteristics, one of which is its resistance to corrosion. However, due to the welding process, stainless steel may present an oxidation layer, this due to welding with deficiente or inadequate shielding gas and with parameters not properly regulated. In order to find a solution to an identified demand, 12 TIG welding experiments were carried out on ABNT 304L stainless steel sheets, analyzing four conditions of purge gas flow. Thus, it was sought to evaluate the best protection condition with purge gas and to optimize parameters such as welding speed control. As a result, experiments with selected purge flow rates protected the root of the weld joint.