Rust Prevention Treatment for Container Houses

Rust prevention treatment for container houses requires a comprehensive approach that considers material properties, coating processes, and regular maintenance. The core methods include selecting weather-resistant steel, implementing a professional anti-corrosion coating system, and conducting regular upkeep.

I. Material Selection and Pre-treatment

Container houses are primarily constructed using weather-resistant steel, which offers superior rust resistance compared to ordinary steel. However, prolonged exposure to humid or salt-laden environments can still lead to rusting. If the base material is carbon steel, strict pre-treatment is necessary:

• Rust Removal: Employ sandblasting or shot blasting to achieve Sa2.5 grade (near-white metal), thoroughly eliminating oxide scale, welding slag, and rust. Ensure a surface roughness of 40-75μm to enhance coating adhesion.
• Degreasing: Use alkaline degreasing agents to remove oil, cutting fluids, and other impurities, preventing coating peeling.
• Rust-Preventive Primer: Hot-dip galvanized steel requires phosphating or nano-conversion treatment; carbon steel substrates should be coated with epoxy zinc-rich primer to provide cathodic protection and prevent substrate rusting.

II. Professional Anti-Corrosion Coating System

Coating is the core aspect of rust prevention and requires selecting appropriate配套 (matching) coatings based on the environment:

• Coating Types:
  • Single-Component Acrylic Paint: Easy to apply without a curing agent, it dries quickly at room temperature (surface dry ≤30 minutes, hard dry ≤6 hours). It offers strong weather resistance, withstanding salt spray, UV rays, and temperature fluctuations (-30℃~70℃), with a protective lifespan of 8-10 years.
  • Water-Based Metal Paint: Using water as a diluent, it is environmentally friendly and pollution-free, drying rapidly, and suitable for container refurbishment. A single application provides long-term rust prevention.
  • Fluorocarbon or Polyurethane Topcoat: Used in highly corrosive environments (such as coastal areas), it offers excellent weather resistance. The total paint film thickness must meet standards, with further thickening required in C5 environments.
• Coating Structure:
  • Primer: Epoxy zinc-rich primer for cathodic protection.
  • Intermediate Coat: Epoxy intermediate coat to increase paint film thickness and seal minor defects.
  • Topcoat: Fluorocarbon or polyurethane topcoat to resist UV rays, rain, and salt spray.

III. Construction Process and Quality Control

• Construction Methods: Support airless spraying, rolling, and brushing, suitable for complex structures (such as welds and corners).
• Environmental Control: Maintain appropriate temperature and humidity during spraying, avoiding dust to prevent paint film sagging and pinholes.
• Thickness Control: Use a film thickness gauge for spot checks. Insufficient paint film thickness leads to rusting, while excessive thickness can cause cracking.
• Weld Treatment: After welding, grind the welds and apply primer to prevent them from becoming corrosion entry points.

IV. Regular Maintenance and Upkeep

• Periodic Inspection: Inspect the coating every 2-3 years, promptly removing rust and applying touch-up paint if rusting is detected.
• Moisture Prevention: Use moisture-proof and thermal insulation cotton indoors to prevent moisture accumulation.
• Sealing Treatment: Seal gaps in the exterior walls to prevent the ingress of humid air.