Q: Compared with sandblasting, how much less durable is rust-inhibitive treatment?
A: Rust-inhibitive treatment (St2/St3) is maintenance-grade; its long-term durability is usually lower than that of a sandblasting (Sa2.5) + zinc-rich heavy anti-corrosion system. The specific gap depends on the environmental grade and design service life, and cannot be generalized, but it is an industry consensus that rust-inhibitive treatment should not replace sandblasting in main heavy anti-corrosion specifications.
Q: What are the consequences of incomplete degreasing?
A: Oil stains form an isolation layer between the metal and the coating, causing severely reduced adhesion and localized large-area peeling, and the subsequent conversion liquid cannot contact the rust layer either. Degreasing must be the first step and cannot be omitted.
Further Reading
- Rust Converter Principles and Application: The complete mechanism and process of conversion-type pretreatment in rust-inhibitive coating.
- Rust Stabilizer Field Application: Stabilization-type pretreatment and key field application points.
- Steel Structure Anti-Corrosion Engineering Specification: Design boundaries for when rust-inhibitive treatment must be abandoned and sandblasting heavy anti-corrosion resumed.
- Neutral Salt Spray Test NSS Evaluation: Reading Methods per GB/T 1771, ISO 9227 and ASTM B117
- Anti-Corrosion Paint Salt Spray Resistance Test: DIN EN ISO 9227 and GB/T 1771