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Article Summary |
To protect metal buildings from rust, a good anti-corrosion primer is essential. Minghua Steel Structure's article will explain the importance of anti-corrosion primers.
When metal buildings in everyday use are exposed to corrosion for an extended length of time, the roof and walls of the steel structure workshop will undergo immediate and visible modifications. Corrosion can degrade the look of steel components, as well as the structure's load-bearing function. Serious corrosion of the steel structure roof will also appear to be a water leak. As a result, corrosion protection for steel structures is critical, particularly in steel structure pharmaceutical workshops, steel structure food warehouses, and steel poultry farms.
First of all, steel structure anti-corrosion must be based on the use of the environment, to determine the type of anti-corrosion coating. An indoor general corrosive environment may not require weather resistance with a strong top coat. Epoxy paint cannot be used on outside surface layers. Anti-corrosion, long service life without alkyd paint. The need for good corrosion resistance requires the use of a variety of anti-corrosion technologies.
Epoxy universal primer is the mainstream product on the market today. Some manufacturers also call it Epoxy Multi-Purpose Primer. It is a kind of primer designed for smooth non-ferrous metal surfaces (including galvanized surfaces), and the adhesion of this paint is reinforced to ensure its adhesion strength.
The anti-corrosive properties of epoxy universal primers are mainly reflected in the following three aspects:
① Shielding effect
Metal surface coating paint film, the metal surface, and the environment apart, preventing water, oxygen, and ions through the coating to reach the steel surface, play a shielding effect. Prevent metal and water, air, and other corrosive substances in contact and corrosion. Of course, as long as the paint has this function.
② Passivation and corrosion inhibition of pigments
The pigment is an important part of the coating. Antirust pigments act with the metal surfaces to passivate or generate protective substances to improve the protective effect of the coating. The antirust primer is often used in the large activity of antirust pigments, they have a certain passivation effect on the metal. When trace water passes through the paint film, a small amount of dissolved pigment will passivate the metal. The corrosion inhibition can make up for the lack of shielding effect. In turn, the shielding effect can prevent the loss of corrosion-inhibiting ions, so that the corrosion inhibition is stable and long-lasting.
Such coatings are water-based acrylic primer, water-based epoxy primer, and inorganic zinc-rich primer.
Common colors: medium gray, dark gray, iron red.
③ Cathodic protection
In the paint coating, if there are more active metal powders (metals with lower electrode potentials) than steel, they can form cathodic protection of sacrificial anode on steel, similar to galvanization. This protective effect is achieved by adding metal powders that are more active than steel, such as zinc or aluminum powders, etc., to the paint coating, and these active metal powders can form an electrochemical protection with the steel to protect it from corrosion. Zinc-rich coatings are typical of this type of functional coatings: epoxy zinc-rich primer, inorganic zinc-rich primer, water-based zinc-rich primer, zinc plus primer, etc., which have become more popular in recent years.
If you have questions about steel structures and prefabricated steel buildings, visit Minghua Steel Structure to consult our articles.
