Via Nicola Persico, 9 - 23

Gioia del Colle (BA), Italy

Via Giosuè Carducci, 23

Cortenuova (BG), Italy

Galvanisation and Painting

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.

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°)

POLyESTER powder coating

Grating fences are painted using a polyester powder applied on the metal at high temperature. Polyester powder, has the characteristic of being a thermosetting material: it is made of  selected polyester resins that after application has excellent characteristics of resistance to atmospheric agents and ultraviolet radiation, thus guaranteeing colour stability and durability in outdoor environments.

Polyester powder gives the fence an aesthetically pleasing appearance and the uniformity of the colour chosen by the customer from a wide range of variations.

POWDER COATING PROCESS

 

Polyester powder coating is applied on the grating that has been previously galvanised
 
  • Acid etching (to remove white zinc oxides)
  • Rinsing with deionised water
  • Alkaline degreasing (perfect cleaning of the entire surface)
  • Deionised water rinse
  • Activation (preparation of the surface for subsequent treatment)
  • Fluorine-phosphating with zinc salts (fixes a microcrystalline layer on the metal surface that improves adhesion and prevents flaking of the coating)
  • Rinsing with deionised water
  • Passivation (removes all traces of chemically unfixed salt)
  • Drying at 140°degrees Celsius
  • Electrostatic application of thermosetting polyester powder
  • Polymerisation in oven at 200° degrees Celsius

RAL COLOR CHART

EMMEGI spa fences are available in a wide range of colours