Technology of cold galvanizing: zinc enamel

Types of metal galvanizing

There are several ways to bond zinc and steel to obtain a corrosion-resistant material:

• hot;
• is galvanic( it is also electrochemical or electrolytic);
• thermodiffusion;
• cold( coloring);
• gas-thermal( spraying).

The first three options are feasible only in the scale of large-scale production, they require serious industrial capacity, energy consumption and waste treatment incompatible with domestic use. In addition, all these methods have limitations on the size of the product. Steel after this galvanizing falls on the construction market in its final form.

The gas-thermal method is used for galvanizing large metal structures that can not be coated with an anti-corrosive compound industrially because of their size. The coating turns out to be scaly, porous and requires additional processing with paint and varnish compositions, but after such a combination the metal structure will last about 30 years.

The cold method of galvanizing is the only method available at home and is not limited in the size of the workpiece. At the same time in many respects it is not inferior to the industrial galvanizing of steel.

Enamel zinc-containing for metal

Application of primer or enamel with zinc content is cold galvanizing. In the composition of dried enamel, the content of atomized zinc reaches 89-93%( the higher the zinc content, the more reliable the corrosion protection of the finished product).

Cold galvanizing technology has its advantages with respect to all other ways: the

• can be hand-made;
• is suitable for machining large or fixed metal structures;
• can independently adjust the thickness of the protective layer and zinc saturation;
• , if used correctly, is several times longer than the hot dip galvanizing service;
• has a decorative function.

However, this method of anti-corrosion treatment and minuses:

• low resistance to mechanical damage;
• high toxicity of the formulation during application;
• impossibility of self-elimination of damages( for hot-dip galvanizing, for example, any inaccuracies in the application are self-destructed due to the formation of zinc oxide).

Weighing pros and cons in the case of cold galvanizing technology, more and more people decide to try this method of steel processing with their own hands.

How is zinc-coated anti-corrosion enamel applied?

The technology is quite simple and can be implemented successfully the first time. To do this, it is sufficient to follow the instructions prepared by the specialists:

1. Metalware should be cleaned of dust, old coating and corrosion, without using acids. Do not use hard abrasives and brushes to avoid damaging the layer of early galvanizing. Excellent washing with water under high pressure.
   

   Note! Galvanized steel can also exhibit corrosion in the form of a whitish coating or yellowing of the metal.

2. The surface is degreased in a standard way using a solvent.
3. Be sure to shake the primer or paint before use.
4. Apply alternately 2-3 thin layers of enamel, each following starting only after the previous one has dried completely.

Note! It is important to apply the layers as evenly as possible so that the galvanizing as a result has the same thickness over the entire surface without gaps.

After complete drying of the last layer, you get a high quality zinc coating and a decorative look of the metal structure.

Note! Apply cold galvanizing on the structure better and faster with a spray gun, although a roller or brush is also suitable.

Zinc enamel: proven

The building materials market is not deficient in priming or enamel zinc compositions. The most common among them are:

• primer enamels and primers ZINOL, ZINOL-SV, ZINOTAN, ZVEZ, ZVOZ-MO, TsINEP, ZINOTHERM, TSINMASTIC, SBE-111 "UNIPOL" AM, VL-023, VL-02, GF-021;
• coating material POLITON-UR, POLITON-UR( UV), POLITON-AK.

Choose among them is not difficult, guided by their own requirements and the price of materials.