CORROSIVE DETERIORATION OF ASSEMBLY COMPONENTS IN AN ELECTRICAL TRANSMISSION TOWER

Abstract

The objective of this work was to characterize the corrosive deterioration of the galvanized
components of assembly of the structure of an electrical power transmission tower. For this, a visual
inspection accompanied by a metallographic analysis, thickness measurement of the galvanized,
morphological analysis by scanning electron microscopy (SEM) with chemical microanalysis
by dispersive energy (EDX) was carried out. The results obtained show that the metal components evaluated have two clearly differentiable zones in terms of surface tonality: a clear and a dark zone, which indicates the presence of a preferential corrosive deterioration of the coating. The microanalysis by EDX carried out in these zones shows that the damage by corrosion and the consequent loss of thickness of the zinc protective coating of the evaluated components is associated with the presence of atmospheric pollutants. It is concluded that the capacity of protection against corrosion of the galvanized remaining in function of the aggressiveness of the environment to which they are exposed by the proximity of an industrial zone, is one of the main causes of the deterioration.

Keywords: Galvanized, transmission towers, corrosion, contaminants, industrial atmosphere.

References

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