What rust prevention methods are used for cold-rolled coils?

2025-09-15 10:12:53

To enhance corrosion resistance and extend service life, cold-rolled coils typically undergo the following rust prevention treatments: Oil coating: Applying a thin layer of rust-inhibiting oil to form a protective film; Passivation: Chemically forming a dense oxide layer on the surface (e.g., chromate passivation); Galvanising (hot-dip or electro-galvanising): Depositing a zinc layer to protect the substrate through sacrificial anodic action; Colour coating: Applying a decorative and protective coating to the surface; Film lamination: Covering with a plastic film to prevent scratches and moisture exposure during transport and storage. The cost and effectiveness vary across these rust prevention methods, necessitating selection based on the usage environment and storage duration. For instance, oil coating may suffice for short-term storage, while galvanising or colour coating is recommended for long-term outdoor applications.