Firstly, ultra-thin fire-resistant coatings have become a hotspot in the research and production of fire-resistant coatings for steel structures in China. Ultra-thin fire-resistant coatings are commonly used solvent-based fire-resistant coatings for steel structures. Compared to traditional fire-resistant coatings for steel structures, ultra-thin fire-resistant coatings for steel structures exhibit superior decorative properties. The thinner coating layer significantly reduces the application workload in engineering projects, thereby lowering the overall cost of the project. It is a product widely promoted in the market.

 However, in steel structure fire protection engineering, the one-sided pursuit of thinner and thinner coatings, as well as the unilateral promotion and publicity of ultra-thin coatings, is extremely detrimental to providing reliable safety guarantees for buildings. The performance of ultra-thin fire-resistant coatings for steel structures primarily depends on the physicochemical reactions of the organic components in the formula. Any factors that affect the carbonization and expansion properties of the coating will impact its ultimate flame retardancy. After long-term application, it is difficult to ensure that the fire-resistant lifespan of the components can last for more than 2 hours.

Secondly, designers often simply point out the use of fire-resistant coatings for the protection of steel structures without specifying which type of fire-resistant coating has been carefully selected for the steel structure. During construction, factors such as price and aesthetics are simply considered, leading to improper selection of flame-retardant coatings.

 Thirdly, environmental selection and essential architectural requirements are often overlooked. When fire-resistant coatings are exposed to sunlight and rain, the steel structure at the top of high-rise buildings is covered with transparent panels, and the environmental conditions are even more demanding. Therefore, outdoor steel structure fire-resistant coatings should be S-type fire-resistant coatings. Fourthly, utilizing technical performance to meet the indoor requirements of outdoor coatings.

 (1) Non-intumescent fire-resistant coating refers to non-intumescent Yulinsheng fire-resistant coating, which inherently possesses flame retardancy or non-flammability. It forms an inorganic enamel-like protective layer in the fire-extinguishing gas released by flames or high temperatures, thereby isolating the air and achieving fire prevention purposes. Non-intumescent fire-resistant coatings can be divided into two categories based on their film-forming materials: inorganic coatings and organic coatings.

 Inorganic non-intumescent coatings use inorganic salts such as sodium silicate, silica sol, and cement as film-forming materials (mixtures) and are mixed with inorganic pigments such as mica, asbestos, and borides. Sometimes organic polymer lotions are added to improve the coating performance. Steel structure fire-resistant coatings are mainly used for building fire protection or temporary fire protection.

 Organic non-intumescent fire-resistant coatings are known as anti-adhesion coatings. They typically utilize halogen-containing film-forming materials. Halogen-containing resins exhibit flame retardancy and self-extinguishing properties. Their effectiveness follows the order of iodine > bromine > chlorine > fluorine. If halogen-containing film-forming materials are not used, retarders containing phosphorus or halogens must be added. Antimony oxide is incorporated into the formulation to enhance toughness. In addition to antimony oxide, other additives include aluminum hydroxide, asbestos, mica powder, phosphates, oxides, glass powder, borates, etc. Pigments not only serve as flame retardants but also constitute the primary substances that form a protective glaze layer during combustion.

 The fire-resistant coating is thicker because the protective layer formed by non-intumescent fire-resistant coating during the M-type combustion process is thinner, resulting in poorer thermal insulation performance. This type of fire-resistant coating can only resist instantaneous high temperatures and flames.

(2) Fire-resistant Coating: Intumescent fire-resistant coatings can expand and char at high temperatures, forming a uniform and dense honeycomb-like or sponge-like carbon foam layer, with a thickness several dozen or even several hundred times thicker than the original film. It not only has good oxygen-blocking effects but also excellent thermal insulation effects. In addition to forming non-flexible foam, chemical and physical changes, such as the decomposition and melting of components in the coating, can absorb heat energy from the scene or from common flame retardants. The non-flammable gases decomposed by the coating are dilute harmful gases such as ammonia and water. These effects make intumescent fire-resistant coatings impervious to small fires. Large fires can prevent the spread of flames and reduce the speed of flame propagation. It is a truly effective fire-resistant coating. Jiangxi Youlinsheng Fire-resistant Coating