HOT-DIP GALVANIZING /

SIGILLO VERDE®

SIGILLO VERDE® hot-dip galvanizing is a metallurgical treatment that protects against rust. It is a technological evolution of traditional hot-dip galvanizing carried out according to the new international standards and increasing requirements of environmental sustainability.

USEFUL VESSEL DIMENSIONS: 13.000 x 2.000 x 3.200mm

No maintenance

Hot-dip galvanizing SIGILLO VERDE® requires no maintenance, operates from the first day to the last day without additional overhead

High resistance

SIGILLO VERDE® hot-dip galvanizing is an actual alloy between steel and zinc. This results in a very tough surface that is difficult to scratch. It is highly resistant to scrapes and abrasions. It can be handled without special care and precautions.

Active protection

Where it is scratched, and the steel has been revealed, the cathode effect is activated which limits the formation of rust in the scratched area alone.

Internal and external protection

The process creates a steel-zinc alloy layer on both the outer surfaces and inner surfaces (example: a tube).

None structural alteration

The class 1 zinc coating, according to EU regulation EN 24286, and where allowed, makes it possible to avoid the radiographic testing of welding seams and product components as provided by EN 1090.

What is it for

SIGILLO VERDE® hot dip galvanizing allows you to:

Protect steel from rust, or what we commonly call iron
Eliminate the typical maintenance against rust on metal products protected with paint
Preserve the structural characteristics of the metal elements
Safeguard the sturdiness of the weld seams
Preserve the environment and non-renewable resources
Declaration of Conformity according to the UNI EN 10204 standard for every lot

Where you can use it

SIGILLO VERDE® hot-dip galvanizing can be performed on all manufactured products made of carbon steel with maximum dimensions of 13,000x2,000x3,200mm 7.000 kg max.
SIGILLO VERDE® hot-dip galvanizing is an anticorrosive system that can be used in all environments: natural, urban, industrial areas and even in aggressive environments.
By definition, hot-dip galvanizing is a metal casting corrosion protection treatment with no aesthetic value, other than its natural conformation and transformation over time.
View some application examples in the "Projects" section.

What does it consist of

SIGILLO VERDE® hot-dip galvanizing is performed according to European UNI EN ISO 1461 standard or, on request, according to other international standards such as the American ASTM. After a series of immersions in the preparation baths, the metal parts are submerged in a tank containing molten zinc at 450°C.
The zinc combines with the carbon present on the surface of the article forming a surface alloy with a thickness which can vary from 50 to 150 microns.

Sustainability

SIGILLO VERDE® hot-dip galvanizing is performed in a Class 1 zinc bath according to EU standard EN 24286, the only one that allows us to preserve all the mechanical characteristics of steel and weld seams otherwise to be verified, as required, according to EU Standard EN 1090. The SIGILLO VERDE® hot-dip galvanizing is performed on an EMAS signed plant and has the Environmental Product Declaration EPD.

What is the life expectancy of the zinc coating

"The zinc coating provides corrosion protection by sacrificing itself instead of the" iron" and, thanks to its oxidation times, significantly higher than those of iron, it guarantees protection for several years. The hot-dip galvanizing method has different life expectancies depending on the environment in which it operates. To determine the life expectancy, it is therefore necessary to identify the Category of Environmental Corrosion.

Short video sulle fasi del trattamento

Description of the main treatment phases

The paragraphs below provide a short description of the main treatment phases:

PREPARATION: the materials are hung using iron wire and/or chains/equipment to "frames" to allow handling throughout the entire production process.
DEGREASING: removal of oil and grease from the surfaces of the manufactured elements by immersion in an acidic degreasing solution, with the addition of surfactants.
PICKLING: elimination of the iron oxides and ferrous rolling mill residues, by immersion in solutions composed of Hydrochloric Acid (HCl) and Water (H20).
WASHING: elimination of acid residues, left by previous phases, by immersion and rinsing in water.
FLUSHING: immersion of the elements in an aqueous solution of "double salt" consisting of Zinc Chloride and Ammonium Chloride (ZnCl2-2NH4Cl).
PREHEATING: the elements are heated in a drying oven at about 100-120°C so as to dry the flushing salts and reduce the thermal shock when it is immersed in the galvanising bath.
GALVANISING: immersion in a bath of molten zinc (min. Zn 98.5%) at a controlled temperature of 440-450°C.
COOLING: Natural air cooling at room temperature.
REMOVAL AND CONTROL: removal of the material from the frames, quality control and finally packaging and finishing.

SIGILLO VERDE®