1. Chemical method: Use pickling paste or spray to help repassivate the rusted parts and form a chromium oxide film to restore their corrosion resistance. After pickling, it is very important to rinse properly with water in order to remove all contaminants and acid residues. After all the processing is complete, repolish with polishing equipment and seal with polishing wax. For minor rust spots, you can use a 1:1 mixture of gasoline and engine oil to wipe them away with a clean cloth.

2. Mechanical methods: Sandblasting, shot peening with glass or ceramic particles, burr removal, brushing, and polishing. Mechanical methods may be used to remove contaminants caused by previously removed, polished, or buried materials. All kinds of contaminants, especially foreign iron particles, can become sources of corrosion, particularly in humid environments. Therefore, mechanical cleaning of surfaces should ideally be performed under dry conditions. Mechanical methods can only clean the surface and cannot change the material's inherent corrosion resistance. Therefore, it is recommended to repolish with polishing equipment after mechanical cleaning and seal with polishing wax.

1. Treatment of water ingress into the whole piece: If the angle steel is waterlogged, it should be disassembled immediately and placed in a ventilated place to dry. If the rain exposure is short (within 1-2 days), closely monitor the surface for white rust and address it promptly.
2. Treatment of minor white rust: If minor white rust or spots appear on the surface, disassemble and let it dry until the white rust turns into powder, then wipe it off and cover it with hot-dip galvanized manual spray paint to avoid secondary moisture.
3. Treatment of severe white rust
If the white rust is severe, the white rust attached to the surface must be completely removed, and the surface should be re-sprayed with hot-dip galvanized spray paint to cover it. After drying, avoid getting it damp again.
4. Optimize the storage environment. During the rainy season, keep the storage environment ventilated and dry, and avoid direct contact with damp ground or soil. When storing outdoors, it is recommended to cover it with a rainproof cloth.

Cleaning methods for hot-dip galvanized steel strip generally include: alkaline washing, alkaline immersion, electrolytic cleaning, and hot water rinsing. These cleaning methods can control the total amount of residual oil and carbon on the surface of the galvanized steel strip to a very low level. Moreover, the surface of the galvanized steel strip is also ground during cleaning, which to a certain extent improves the adhesion of the steel strip surface. Therefore, cleaning hot-dip galvanized steel strip is essential.