Fireproof paint thickness requirements

GB14907-2002 "Fireproof Coatings for Steel Structures" stipulates that the thickness of fireproof coatings for thick steel structures is 7-45㎜. In the construction process of steel structure fire retardant paint, there is no clear regulation on the thickness of fire retardant paint, only the thickness required to reach the paint is proposed. Due to differences in the hazard levels of public buildings, important public buildings need to be strengthened and protected. Therefore, the choice of fire retardant coating thickness is very important. Under the premise of ensuring building safety, how to use fire retardant coatings efficiently and economically is very important. Is the thicker the fire retardant coating, the better the fire performance?
It is important to know that as the thickness of the fireproof coating increases, the temperature of the steel column surface continues to decrease, but the temperature decreases by a different degree. When the thickness of the fireproof coating is small, increasing the thickness of the fireproof coating can effectively reduce the temperature of the steel column surface. When the thickness reaches 25mm, as the thickness of the fireproof coating increases, the decrease in temperature of the surface of the steel column gradually decreases. Considering that the fire retardant coating is too thick, it is easy to fall off and crack due to various factors. At the same time, considering economic reasons, when the thickness of the fire retardant coating exceeds 25㎜, it is not appropriate to continue to increase the thickness of the fire retardant coating to increase the fire resistance of the steel structure. Appropriate use of other protection methods to achieve the best fire protection plan. Coating thickness gauge can be used to measure the fireproof coating thickness.
It can be seen that the protective effect of fire retardant coatings on steel structure buildings gradually decreases as the thickness of fire retardant coatings increases, and the fire retardant coatings are likely to fall off due to environmental factors afterwards, so it cannot mean that the steel structure buildings are realized by increasing the thickness of fire retardant coatings. Safety under fire. In addition, the thermal conductivity of the fire retardant coating has a greater influence on the temperature of the internal steel structure. For buildings with greater fire risk, it is advisable to use a fire retardant coating with a lower thermal conductivity instead of increasing the thickness of the fire retardant coating to achieve the fire resistance required by the building structure. limit.