Knowledge about fire and flame retardant

Knowledge about fire retardant

Types

There are many types of fire retardant coatings, but according to the use objects of the fire retardant coatings and the coating thickness of the fire retardant coatings , Generally divided into decorative coatings and steel structure fireproof coatings.
Finish-type fire-retardant coatings are generally used as protective materials for combustible substrates, and have certain decorative and fire-resistant properties. They are divided into two categories: water-based and solvent-based. The steel structure fireproof coating is mainly used as a protective material for non-combustible components. This kind of fireproof coating has a relatively thick coating, low density and low thermal conductivity, so it has excellent heat insulation performance and is divided into organic fireproof coatings. and inorganic fire retardant coatings.

Quality assessment

Since fire retardant coatings are used to retard the spread of fire, what kind of quality fire retardant coatings are good? What are the evaluation criteria? According to the current point of view, domestic fire retardant coatings are divided into one, two and three grades. Of course, the first grade has the best performance. The quality of fire retardant coatings is actually mainly determined by the fire resistance and physical and chemical properties of fire retardant coatings. The fire resistance includes four indicators, such as flame resistance time, flame spread ratio, weight loss and carbonization volume, which can be obtained from the large plate burning method, tunnel burning method and small chamber burning method respectively according to national standards. The physical and chemical properties mainly include solid content, viscosity, flexibility, impact strength, adhesion, drying time and water resistance. Its technical indicators are obtained after testing according to national standards.

Fire resistance

Does the thicker the fire retardant coating, the better its fire resistance? Generally speaking That being said, for non-intumescent fire retardant coatings, it relies on its own flame retardancy and incombustibility to prevent the spread of flames. Therefore, the thicker the coating, the thicker a glaze formed at high temperature, and the thermal insulation effect of the fire retardant coating will be improved. For intumescent fire retardant coatings, the thicker the coating is, the thicker the foam layer will be, and the foam layer that forms oxygen isolation and heat insulation will be thicker. Increase, and organic free radicals, the effect of interrupting the chain reaction is also good. Therefore, in terms of improving fire resistance, the thicker the coating, the better.

Burn in case of fire

Why do some fire retardant coatings also burn in case of fire? To explain this problem, let's first look at the composition of fire retardant coatings, such as base materials, dispersion media, flame retardants, solvents, etc. The fire retardant coating before construction burns in case of fire. In fact, the flammable liquid solvent in the fire retardant coating is burning, while the base material and flame retardant of the fire retardant coating will not burn. Because solvent-based fire retardant coatings use organic solvents as solvents, such as No. 200 solvent gasoline, n-butanol, acetone, cyclohexanone, toluene, etc., once these fire retardant coatings leak from the barrel, it is easy to cause fire. The fire retardant coating applied to the building components can only play the role of fire resistance and heat insulation after the solvent has evaporated.

Fire resistance

Is it effective to improve the fire resistance of building components by treating with fire retardant coatings? With the development of flame retardant science in China, advanced, High-quality fire-retardant coatings came into being, and the effect is obvious from the perspective of normal application.

Classification

Finishing fire retardant coating; wood fire retardant coating; steel structure fire retardant coating, concrete structure fire retardant coating, tunnel fire retardant coating, cable fire retardant coating .
Fireproof coating is composed of coating components such as binder (ie film-forming substance), pigment, common coating additives, fireproofing additives and dispersing medium. Except for fire retardant additives, other coating components have the same functions in coatings as in ordinary coatings, but some have special requirements in terms of performance and dosage.