How To Select Anti-Corrosion Processes For Substation Steel Structures

The anti-corrosion treatment of substation steel structures should be selected based on environmental conditions, material properties, and the required corrosion protection lifespan. It should combine the characteristics of technologies such as hot-dip galvanizing, anti-corrosion paint coatings, cold zinc spraying, and metallic coatings. Specific approaches are as follows:

1. Hot-Dip Galvanizing Technology:

Steel components that have undergone rust removal are immersed in molten zinc at high temperatures, forming a zinc coating on the surface to prevent corrosion. The corrosion protection lifespan is proportional to the thickness of the zinc layer. This method is suitable for outdoor steel structures exposed to severe atmospheric corrosion and where maintenance is difficult, such as transmission towers and communication towers.

Advantages: Excellent corrosion resistance, long service life, minimal maintenance required.

Disadvantages: After extended use, zinc salts may form on the surface, causing discoloration.

2. Anti-Corrosion Paint Coating Technology:

During the processing and use of steel structures, paint coatings are applied to slow down corrosion. The system includes pre-coating primers, rust-proof primers, intermediate coats, and topcoats.

Pre-Coating Primer: Provides temporary protection during workshop processing before applying rust-proof primer, after treatments such as sandblasting or phosphating.

Rust-Proof Primer: Must have good adhesion to the substrate; appropriate primers should be selected based on substrate type. Epoxy primers generally offer better corrosion resistance.

Intermediate Coat: Applied between primer and topcoat, provides good filling capacity, helps repair and enhance the base surface, and improves overall coating quality.

Topcoat: Requires excellent weather resistance, corrosion resistance in operational environments, and decorative appearance. High requirements are placed on color, gloss, aging resistance, chemical resistance, scratch resistance, and surface leveling.

3. Cold Zinc Spraying Technology:

This method forms a zinc metallic protective film (zinc shield) on the surface of steel components through spraying, offering both cathodic protection (sacrificial anode) and barrier protection.

Advantages: Energy-saving, environmentally friendly, easy to apply and maintain, low life-cycle cost. It aligns well with the "resource-efficient and environment-friendly" design concept of substations and suits the characteristics of substation engineering.

Application: With recent technological advancements, cold zinc spraying, widely used abroad, has been increasingly adopted in domestic power engineering projects.

4. Metallic Coating Technology:

Involves coatings of zinc and its alloys, as well as aluminum and its alloys. Traditional processes include thermal spraying and hot-dip methods, while cold zinc spraying has gained adoption in recent years.