Avaliação de campos magnéticos emitidos pelos processos eletrodo revestido e TIG

Abstract

Welding arc processes are widely used in metal industry in a wide range of applications. These processes employ high current levels that reach hundreds of amperes and generate magnetic fields, whose harmful effects on human health are not yet fully proven. Even though, bureaus connected to occupational health formulated guidelines that limit exposure of the worker to such fields. Moreover, studies show that, depending on current levels and how the welding is performed, these reference levels may be exceeded in some cases. Therefore, the objective of this work is to carry out weldments by using the covered-electrode and TIG processes, since they are mostly performed manually, to evaluate the influence of variables such as welding current, arc length, shielding gas, material and coating on magnetic-field values and compare them to the threshold limits established by the latest directives of the ICNIRP. The results showed that the magnetic field is higher as the higher the welding current and the lower the greater the height of the arc. The electrode coating influences the value of the magnetic field to be associated with arc stability. The shielding gas influences the magnetic field by modifying the arc format. Finally, the magnetic field is influenced by the magnetic permeability of the base material.