1. Factors affecting the coating quality of steel structure engineering coatings include: derusting quality, film thickness, coating matching, ambient temperature, environmental humidity and many other aspects. Construction and inspection personnel shall strictly follow the acceptance specification GB50205. And pay attention to the quality control of the following links.
2. The surface of the rust-removed steel is easily oxidized when exposed to air. The first primer should be completed within 6 hours after cleaning.
3. Steel surface derusting quality before steel structure engineering is the key factor determining the anti-corrosion effect and service life of the paint film. The quality control requirements for various descaling levels specified in GB8923 must be strictly implemented.
4. Two kinds of harsh working environments are extremely harmful. 1) If the relative humidity is too high and the temperature of the steel component is too low, the surface of the steel will be dew condensation, which will seriously affect the adhesion of the coating on the metal surface. 2) The ambient temperature is too high, the solvent evaporates quickly, causing the drying of the paint film inside and outside is not synchronized, wrinkles, blistering, small holes, and the surface of the coating is not smooth. Therefore, the working environment should be carried out in dry weather (relative humidity below 85%) and outdoor temperature in 5~30. Construction is strictly prohibited under the scorching sun, rainy days, and wet weather. (chlorinated rubber paint can be applied at low temperatures)
5. Only the coating with good process matching can ensure that there is no phenomenon of biting bottom, falling off, foaming and wrinkling between the paint layer and the layer.
6. The paint should be applied evenly. No defects such as leakage coating, sag, exposed bottom or wrinkled skin are allowed.
7. Before the paint film is not dried, protective measures should be taken to prevent rain and man-made damage.
8. The total thickness of the dry paint film must reach the minimum thickness required by the design, and the outdoor should be greater than 150μm, and the indoor should be greater than 125μm. The thickness of the paint film should be measured at any time using a film thickness gauge. The surface roughness of the sandblasted steel is large, and attention should be paid to increasing the thickness of the primer so that the peak portion is completely covered.
9. The coating interval per coating is strictly in accordance with the coating instructions to prevent the new coating from softening the coated coating.
10. In the hole and the concave joint, use a paint brush to spin vertically.
11. The surface of the weld should be thoroughly treated, and the residue of welding slag and splash should be removed. The protruding part of the weld surface should be completely covered.
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