In fact, the choice of anticorrosive primer for steel structure engineering needs to consider five main factors, such as the surface treatment of steel structure, the environment in which it is located, the type of top paint that needs to be matched, the temperature of use, and some special corrosion conditions. Don't say don't know, the details are as follows:

1. Surface treatment of steel structure

Different types of paint have different requirements for the treatment of steel structure substrates. There are strict requirements and zinc-rich primers that are sandblasted to Sa2.5 or higher, and there are epoxy iron red and red that can remove rust. Dan anti-corrosion, etc., as well as rust-containing anti-corrosion paint that can be slightly rust-painted. At the same time, the pretreatment of the steel structure surface is divided into galvanized steel structure, chemical treatment steel structure, ordinary carbon steel steel and so on. The steel structure primer must be treated to a certain standard on the surface of the steel structure to have good adhesion, thereby ensuring the anti-corrosion effect. Different types of steel structure primers have different requirements for the indicated treatment, and according to the anti-corrosion requirements, corrosion Depending on the environment, the surface treatment level also changes. The requirements of the primer coating for the rust removal grade of the steel surface shall meet the requirements of the following table. The surface of steel with rust grade of D should be sprayed or projected to remove rust.

2. Whether there are special corrosion factors.

Strong acid, strong alkali, solvent oil, salt spray, etc. must be protected from the primer. In addition, water and humid environments are severely corroded, and high-performance anticorrosive primers are also required, such as epoxy zinc-rich primer, inorganic zinc-rich primer, etc.

3. The use temperature of steel structure equipment

Most paints can only be used at room temperature. If you need to use it in a high temperature environment, you must choose high temperature resistant anticorrosive paint, such as inorganic zinc-rich primer and *silicone high temperature resistant paint.

4. The top paint used for steel structure anticorrosion

The compatibility of anti-corrosion paint and topcoat should be fully considered to avoid coating problems caused by non-matching. For example, although alkyd anticorrosive paint is easy to apply, it cannot be used with two-component high-performance anticorrosive topcoat, and epoxy zinc-rich primer cannot be used with alkyd enamel.

5. The environment where the steel structure is located

Before choosing an anti-corrosion paint, you should fully consider the corrosion factors of the use environment of the steel structure. If the corrosion is slight, you can use ordinary anti-corrosion paint. For seaside, chemical plants, bridges, etc., if the corrosion is serious, or for important steel structures, high-performance anti-corrosion bottom should be used. paint.

Painting the surface with special anti-corrosion paint is still the main method of anti-corrosion of steel structure engineering and grid frame. Anticorrosive paint can be divided into primer, middle coat and top coat according to its protective function. Each layer of paint has its own characteristics, and each layer has its own responsibility. Several layers are combined to form a composite coating, which improves the anticorrosion performance and prolongs the service life.