High-rise steel structure buildings are increasing day by day, especially some super high-rise buildings, which use steel structure materials more widely. Steel structure is a structure composed of steel materials, which is one of the main building structure types. Steel itself has super thermal conductivity, and its tensile strength is closely related to the heating temperature. Therefore, the prevention of fire resistance of steel itself is a problem that must be paid attention to in steel structure engineering, and the fire protection of major bearing components in steel structure building is the most important one.

One of the main means of fire protection for steel structures is to spray fire retardant coatings on the surface of structures. At present, there are four main fire-proof coatings: ultra-thin steel structure fire-proof coatings, thin steel structure fire-proof coatings, thick steel structure fire-proof coatings, mineral cotton building fire-proof and heat-proof coatings. At present, like some steel structures such as factories, factories and storehouses, thin fire retardant coatings are commonly used.

Thin-coated fire-retardant coating for steel structure refers to coating thickness greater than 3 mm, less than or equal to 7 mm, which has certain decorative effect. This kind of fire-retardant coatings for steel structures usually use suitable water-borne polymers as binders. It is required that the selected water-borne polymers have good adhesion, durability and water resistance to the steel substrates. Their general fire resistance limit is less than 2 hours, and spraying construction is usually used.

The basic treatment should be carried out before the construction of thin fire retardant coatings. That is to clean the surface of the steel structure to be sprayed and check the integrity of the steel structure. When spraying, dirty liquid pollution should be prevented, and the relative humidity of air should not be too high, the air should be circulated, and when there is dew on the surface of components or rainy days, it should not be operated.

In selecting and purchasing materials, we should pay attention to whether the product quality meets the requirements of relevant standards, check the name of paint varieties, technical performance, production batch number, storage period and use instructions. Fire retardant coatings should be matched with surface coatings, and non-corrosive steel should be used as bottom coatings. Generally, after finishing the spraying of the bottom layer, the second spraying should be done more than 24 hours later. The spraying machine is recommended for the bottom layer and the main layer, while manual painting is recommended for repairing and small area construction. Rolling painting can be used for construction.

When spraying, the spraying gun should be perpendicular to the surface of the sprayed steel component, the spraying distance is 6-10mm, and keep at 0.4-0.6MP. The running speed of the spraying gun should be stable, and it can not stay in the same place for a long time, so as to avoid the accumulation and flow of paint. When spraying, it is necessary to ensure that the supply of coatings is timely and that no material breakage or shortage occurs. After spraying, the machine should be cleaned in time to facilitate the next use.

After spraying, it is necessary to ensure that the fixed-line effect of the coating is good, and the bonding should be firm, and the phenomena such as pulverization, hollowing and falling off should not occur. It is necessary to ensure that there are no obvious depressions at the joints and corners of the steel structure, and that there are no slurries or cracks on the surface of the coating.

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Above is the construction procedure and precautions of the thin fire retardant coating for steel structure introduced by Tuhuite. If you have other questions and suggestions, please leave a message for inquiry.