Anti-corrosion coating construction process for steel structures？

1. Strictly implement standards and specifications (1) "Code for Acceptance of Construction Quality of Steel Structure Engineering" GB50205-2001; (2) "Surface Treatment of Steel Materials Before Coating - Visual Assessment of Surface Cleanliness Part 1" GB/T 8923.1-2011.

2. Process flow: base surface cleaning → base coating → intermediate coating → topcoat coating.

3. Base surface cleaning

(1) Before coating, check whether the steel structure fabrication and installation have been accepted. Before painting, remove rust, weld spatter, oil stains, dust, etc. from the parts to be coated.

(2) To ensure the quality of the coating, an automatic shot blasting machine is used for rust removal. This rust removal method uses the pressure of a compressor to continuously impact the surface of the steel structure with steel shots to clean up rust, oil stains, and other debris on the surface of the steel, revealing the original color of the metal steel. This method is a highly efficient, thorough, and advanced rust removal process.

4. Primer coating

(1) Mix the anti-rust paint, control the viscosity, consistency, and dilution of the paint, and stir it thoroughly during mixing to make the paint color and viscosity consistent.

(2) When spraying the layer of primer, the brushing direction should be consistent and the joints should be neat.

(3) When spraying the primer, the principle of frequent movement and short intervals should be adopted to prevent excessive spraying and dripping.

(4) After the coat is dry, spray the second coat. The second coat should be sprayed in a direction perpendicular to the coat. This will make the paint film thickness uniform.

Intermediate coat coating

After the primer is sprayed, spray the intermediate coat. The coating material should be in accordance with the design requirements and should not be changed at will. The brushing method and direction are the same as the primer coating.

Topcoat coating

(1) The topcoat material should meet the design requirements and attention should be paid to the compatibility of the properties of the base and top coats.

(2) Topcoat preparation: Choose a topcoat of the same color and mix it with appropriate thinner. Stir the topcoat thoroughly before use to keep the color uniform. Its working viscosity and consistency should ensure that it does not drip or show brush marks during painting.

(4) The topcoat should be stirred continuously during the painting process. The brushing method is the same as the primer coating.

Coating inspection and acceptance

(1) Post-painting treatment inspection: the coating color should be consistent, bright, and shiny, without wrinkles or bumps. (2) During and after surface coating construction, protect the painted work to prevent flying dust and other debris.

(3) Determination of coating film thickness: Use an angle-point coating film thickness gauge to measure the coating film thickness. The coating film thickness gauge generally measures the thickness at three points and takes the average value.

5. Environmental requirements

The ambient temperature should be in accordance with the product manual of the coating. When there is no requirement in the product manual, the ambient temperature should be between 5 and 38°C, and the relative humidity should not be greater than 85%. During coating, there should be no condensation or moisture on the surface of the component. It should be protected from rain within 4 hours after coating.

6. To prevent accidental coating, the parts prohibited from coating by design requirements or steel structure construction process requirements must be shielded before coating.

7. After coating, the components should be temporarily enclosed and isolated to prevent trampling and damage to the coating. They should not come into contact with acidic liquids to prevent biting of the coating. When transporting, they should be prevented from being bumped or dragged to damage the coating.