Galvanising

Galvanising metals

Galvanisation is a process which slows down rusting and improves the technical performance of metallic objects, usually in steel, but which can also be copper, brass or cast-iron.

Objects undergoing galvanisation are treated with a covering of zinc to protect them from galvanic corrosion and limiting the formation of electrolytic micro-celles with anodic action.

The galvanisation protects the object because the zinc – being a less noble metal than iron in terms of corrosive environments – is eroded first, thus impeding the corrosion of the iron material, up until on the surface of the object zinc metal is revealed.

Galv.Ar offers services of static galvanic coating and barrel galvanic plant.

  • with regard to static galvanic coating, the elements to be coated are attached to plastified frames, which are hung from bars. The bars are then moved onto a bridge conveyor to carry out the cycle. The frames are used to pass current through the pieces.
  • the barrel galvanic plant is particularly suitable for very small metallic pieces and, in this case, the pieces are loaded into equipment which is plastic-coated and which comprises a prism with a hexagoal base (the barrel). This is then made to rotate around its own axis.

 

The plating is normally followed by a passivation phase involving chemical treatments and which take their name from the aesthetic result which they produce: Blue, Yellow or Black passivation. Cleanliness, durability and resistance to atmospheric and chemical agents are just some of the many advantages offered by galvanic zinc coating. Over the years, Galv.Ar has acquired vast experience in galvanic zinc coating, working to high standards of efficiency and guaranteeing the excellent quality of the end product whilst respecting all the environmental protection legislation. The strong links and collaboration which Galv.Ar has established with many companies in the area, and the substantial repeat business which the company enjoys underline the quality and reliability of the service offered.

Materials which can be treated: Copper, Brass, Steel.

Characteristics of the Static Galvanisation Plant:

  • Automatic plant with alkaline solution
  • Maximum dimensions treatable: 6,000 x 1,400 x 650 mm
  • Thicknesses applied: depending on request or specification, generally from 8 to 12 microns
  • Saline Mist Resistance: from a minimum of 48 hours to a maximum of 300 hours
  • Resistance to low temperatures: as low as -65°C
  • Resistance to dry heat: approximately 200°C

The surface appearance of material after zinc coating, may be semi-polished or gloss depending on the material used. The colour of the coating varies according to the type of passivation requested: Blue or Yellow. All the solutions are free of hexavalent chromium (cr6), as required by the ROHS directive.