Finishing, materials and treatments
The chain does not undergo surface treatments after the production process.
It is the most price-effective solution for uses that do not require protection against corrosion.
The raw chain is generally sold in continuous length for customers that re-employ the product in various industrial works or marina building.
The chain is treated in sifters and vibrators with the addition of natural materials that confer a shiny aspect and an extremely smooth surface, through constant motion contact.
The process does not ensure protection from rust, but improves the product’s aesthetics.
The electro galvanizing treatment ensures resistance from atmospheric agents.
It is carried out in continuous length or barrel, according to the semi-finished product that is supplied with even deposit, also in the contact points of chain links.
In particular, the treatment carried out by qualified and certified suppliers, complies with UNI EN ISO 2081 standard and generally undergoes a light blue passivation process.
In conclusion, various passivation processes can be requested, as those of tropical type.
Hot deep galvanizing
Hot deep galvanizing consists in immersing steel objects in a bath of molten zinc, kept at an average temperature of 450 °C, that plates the steel with a thin and resistant zinc layer.
Thanks to the pre-treatment in a bath of molten salts of zinc chloride and ammonium chloride, the steel binds to the zinc, conferring a much higher resistance to corrosion compared to electro galvanizing, also due to the greater mechanical resistance of the protective layer that is also effective against salt and galvanic currents.
Pursuant to UNI EN ISO 1461 standard, the process consists of the following phases:
1) degreasing and pickling, using surface-active agents and hydrochloric acid;
2) fluxing by immersion in ammonium chloride and zinc chloride solution;
3) galvanization through immersion, after pre-heating at 100°C, in molten zinc vat at 450°C, for the time required for the steel to reach the same temperature of the zinc;
4) cooling in air or water, followed by a potential passivation treatment.
Two different processes can be implemented to paint metal.
Painting with thermo-hardening electrostatic powders is a coating process with organic film carried out for decorative purposes and to protect against corrosion and aggressive agents.
Micaceous painting applies an anti-corrosive enamel to the steel, consisting of resins, iron oxide and special water-repellent pigments. The exterior aspect is antiqued, ideal for applications in urban furnishing.
The process foresees inputting the product inside a preparation tunnel in steel, then in an automatic painting booth and subsequent finishing in a drying furnace.
The products in stainless steel ensure utmost resistance against oxidation.
We use two types of steel: AISI 304L for protection against atmospheric agents and AISI 316L also suitable in acid, galvanic and salty environments.
The production process of stainless steel chains ends with polishing which confers a shiny aspect to the finished product.