The rinsing phase is a very important step, which must be carried out before the subsequent galvanizing step. In fact, rinsing is necessary to remove any residues of chemicals and oils deposited in the previous cleaning steps.
It is important that the galvanized product comes to the uncontaminated galvanizing phase: on the contrary, if this did not happen, the subsequent treatments and the final result would be compromised, with any defects in uniformity of the protective film and less resistance over time.
The metal pieces that need to be galvanized later, go through a drying oven whose task is to preheat the articles themselves in order to reduce the thermal shock at the galvanic bath.
In the cooling phase, the artifacts are extracted from the galvanic bath and the excess material is drained. It is a very critical phase because it is important to avoid the formation of drips which would compromise the final result.
Metal pieces, though no longer immersed in the galvanizing bath, are still at high temperatures and the chemical process continues. To stop the process being processed, the artefacts are cooled with a mixture of air and water.
The passivation treatment causes the outer layer of the protective film, the one in contact with atmospheres, to react much more slowly in contact with air and other natural elements.
The treatment is needed to avoid the so-called “white rust” that would form and compromise the aesthetics of building-architectural constructions, for example. It is to be specified, however, that this “white rust” does not absolutely affirm the strength and effectiveness of the underlying protective film.
With the passivation process, galvanizing treatment can be considered complete.