Steel structure fabrication enterprises pursue both efficiency and long-term performance. As a professional manufacturer, we provide a detailed explanation of the standardized coating system centered on epoxy zinc-rich primer, helping your products shorten construction periods while achieving a corrosion protection service life of over 10 years.
In the steel structure manufacturing industry, Epoxy Zinc-Rich Primer is recognized as the "anchor" of heavy-duty anti-corrosion systems. It provides a dual defense line for steel substrates through cathodic protection by sacrificial anodes. But how can its maximum effectiveness be achieved?
1. The foundation of foundations: Sa2.5 grade sandblasting Epoxy zinc-rich primer has extremely high requirements for substrate preparation.
- Requirement: Sandblasting rust removal must be performed to Sa2.5 grade, giving the metal surface a slight "burr" texture.
- Reason: This can greatly increase the contact area, allowing the zinc powder to undergo an electrochemical reaction with the steel, eliminating the risk of paint peeling.
2. Core Parameters: Don't Blindly Pursue High Zinc Content
- Standard: It is not true that the higher the zinc content, the better. Excessive zinc powder will cause the paint film to be brittle and have reduced adhesion.
- Recommendation: For ordinary steel structures, domestic-standard epoxy zinc-rich primer with 60%-70% zinc content offers the best balance of cost-effectiveness and workability.
3. Quick Matching Process (Recommended Solution) To improve workshop turnover rate, we recommend the following matching:
- Primer: Epoxy zinc-rich primer (dry film 60-80 microns) —— provides cathodic protection.
- Middle coat: Epoxy micaceous iron oxide intermediate paint (dry film 100 microns) —— Increases film thickness and barrier properties.
- Topcoat: Polyurethane topcoat (dry film 60 microns) —— Protects the intermediate primer coat and provides decorative finish.
4. Construction Pitfall Avoidance Guide
- Mixing: Zinc powder has a high density and settles very easily. A pressure tank with a mixing function must be used throughout the spraying process.
- Recoat interval: After the epoxy zinc-rich primer is completed, it is recommended to apply the intermediate coat within 24 hours to prevent the formation of zinc salts on the surface that may affect adhesion.
Conclusion: Standardized steel structure painting is a label of a company's quality. Choose our factory-direct high-performance epoxy zinc-rich primer to make every piece of your steel structure product stand the test of time.