Via Nicola Persico, 9 - 23

Gioia del Colle (BA), Italy

Via Giosuè Carducci, 23

Cortenuova (BG), Italy

Hot dip galvanisation

HOT DIP GALVANISATION

Hot-dip galvanisation is the most effective treatment method for protecting ironwork from the aggression of atmospheric agents.

The grating panels, after the washing and pickling treatment that allows a deep cleaning of the metal, are immersed in a bath of liquid zinc. The zinc adheres to the steel, creating a coating of controlled thickness, in accordance with UNI EN ISO 1461 standard.

The freshly galvanised panels are left to cool and individually checked to remove small imperfections. In the days following galvanisation, due to the self-passivating characteristics of zinc, a layer of zinc oxide forms on the entire  surface, protecting the product for decades. Zinc, in fact, being a less noble metal than iron in chemical terms, offers cathodic protection, oxidising itself instead of the metal it covers.

The phases of hot-dip galvanisation:

– Surface cleaning of the product (removing traces of paint, adhesive, cement, etc.);
– Degreasing in an alkaline solution (elimination of oily residues);
– Pickling in hydrochloric acid HCl = 120/130 q/lt (elimination of all oxide layers present);
– Washing (elimination of all traces of acid);
– Fluxing in ZnCl2-NH4Cl solution;
– Drying in dryer;
– Immersion in molten zinc (440° – 460°)

Quality Control

Hot-dip galvanising is carried out in accordance with EN ISO 1461, or alternatively, in accordance with ASTM A 123; ASTM A 153. Hot-dip galvanised gratings are supplied with a Galvanisation Certificate.