The first coat of paint should be applied to the sandblasted steel within 4 hours. If Youlinsheng Fireproof Coating Manufacturer uses ET-98 inorganic phosphate long-lasting zinc-rich coating as the primer, generally, oil and rust removal are sufficient. Sandblasting and shot blasting are not necessary. Instead, steel wire brushes, polishing machines, or steel sandpaper can be used for treatment. Painting can be carried out even with minor rust present.

    In case of welded parts, painting cannot be carried out within 72 hours after candle welding.

    For fire-resistant coatings applied to galvanized surfaces, the galvanized layer must be cleaned of dust, oil, and other impurities using a light sweeping sandblasting method, followed by the application of 70-H epoxy iron oxide red anticorrosive paint.

    Environmental conditions for fire-resistant coatings:

    The environment for applying fire-resistant coatings has a significant impact on the quality of the paint film. To ensure the quality of the coating, the following requirements for the coating environment are proposed:

 (1) Open-air operations should not be conducted under direct sunlight or in rainy, foggy, or snowy weather conditions; construction should not be carried out when the relative humidity exceeds 85%; the temperature of the base material must be at least 3 degrees Celsius above the dew point before construction can proceed. ET-98 inorganic phosphate long-lasting zinc-rich coating is unaffected.

(2) Construction should not be carried out when there is direct sunlight in summer and the substrate temperature is above 60 degrees. When the temperature in winter is not below -5 degrees, 70-H epoxy iron oxide red anticorrosive paint, H06-3 epoxy micaceous iron oxide anti-rust paint, and ZHL51-2 super thick paste epoxy asphalt anti-rust paint should not be applied outdoors.

(3) Construction cannot be carried out when dust is flying during the painting process and the drying time of the paint film. ET-98 inorganic phosphate long-lasting zinc-rich coating is not affected, as it can achieve surface dryness in 3 minutes.

     1) For indoor exposed, lightweight roofs and those with decorative requirements, when the fire resistance limit is specified as 1.5 hours or above, fire-resistant coatings should be selected.

    2) Indoor concealed areas, high-rise buildings, and multi-story factories. When the specified fire resistance limit is above 1.51 hours, thick-coating fire-resistant paint should be used.

    3) For outdoor use, fire-resistant paint suitable for outdoor applications should be selected.

    4) The fire-resistant coating used for protection should be asbestos-free and benzene solvent-free. After drying, it should not emit irritating odors and should not corrode steel. Its performance must be maintained during the predetermined functional period of use.

    5) Fire-resistant coating manufacturers for Youlinsheng must have fire resistance test reports and physicochemical property test reports issued by national testing institutions. They must also have production licenses issued by fire supervision authorities. Only then can they be selected. The quality of the selected fire-resistant coating should comply with relevant national standards. It should have a certificate of conformity from the manufacturer, and should be accompanied by the coating name, technical performance, manufacturing batch number, storage period, and instructions for use.

    6) When selecting fire-resistant coatings, the following points should be noted.

    Do not use decorative fire-resistant coatings, as they are flame-retardant coatings designed to protect combustible substrates such as wood structures. A thin coating film cannot achieve the purpose of enhancing the fire resistance limit.

    ② Thin-applied expansion fire-resistant coatings should not be used to protect structures above 21 stories. The limited fire resistance of thin-applied expansion fire-resistant coatings is determined by their raw materials and fire-resistant principles. These coatings contain many organic components, and the coating layer undergoes physical and chemical changes at high temperatures, forming a carbonaceous bubble film that serves as a heat insulator. However, the strength of the expansion bubble film is limited, making it prone to cracking and peeling. The carbonaceous material gradually ashes at high temperatures of 1000℃. For structures requiring a fire resistance limit of more than 2 hours, other coatings must be selected

Use thick-applied fire-resistant and heat-insulating coatings.

    ③ Indoor fire-resistant coatings must not be directly applied for spraying protection outdoors without being improved and effective waterproof measures taken. The outdoor environmental conditions are much harsher than those indoors. It is completely exposed to sunlight and the atmosphere, subject to sunshine, rain, wind, and snow cover. Outdoor fire-resistant coatings that are water-resistant, freeze-thaw resistant, aging-resistant, and able to withstand chemical corrosion such as acid, alkali, and salt must be selected for spraying protection in the open air.

    ④ Under normal circumstances, outdoor fire-resistant coatings should not be chosen for indoor fire protection. To ensure the excellent performance of outdoor fire-resistant coatings, strict requirements are placed on their raw materials, and some special materials need to be applied. Therefore, their price is much higher than that of indoor fire-resistant coatings. However, for semi-outdoor or certain humid environments, outdoor fire-resistant coatings are suitable for protection.

    ⑤ Thick-applied fire-resistant coatings are primarily composed of inorganic materials. The coating is stable and ages slowly. As long as the coating does not peel off, its fire-resistant performance is guaranteed. Considering durability and fire resistance, it is advisable to choose thick-applied fire-resistant coatings. Jiangxi Youlinsheng Fire-resistant Coating Manufacturer