1. Fireproof glass for construction is divided into composite fireproof glass (FFB) and single fireproof glass (DFB) according to structure.

Composite fireproof glass: it is a special glass composed of two or more layers of glass, or one layer of glass and organic materials, and meets the requirements of corresponding fire resistance rating. Monolithic fireproof glass: it is a special glass composed of single-layer glass and meets the corresponding fire resistance rating requirements.

According to the structural type, fireproof glass can be divided into: fireproof laminated glass, thin coated fireproof glass, single fireproof glass and fireproof wired glass. The fireproof laminated glass can be divided into composite fireproof glass and pouring fireproof glass according to the production process characteristics.

2. Skill requirements for fireproof glass

The fire-resistant function of fire-proof glass for construction is obtained by embedding the fire-proof glass directly in the wall hole or combined with the structure, and then embedded in the wall hole to make components according to gbl2513. It includes the determination of fire-resistant integrity, fire-resistant and heat insulation and thermal radiation intensity. The temperature of the thermal insulation surface is used as the criterion.

According to gb15763 1-2009 according to the rules of fire-proof glass for construction, fire-proof glass for construction is divided into class A (fire-proof glass satisfying the requirements of fire integrity and fire insulation) and class C (fire-proof glass satisfying the requirements of fire integrity). According to the fire resistance rating, the three types of fireproof glass can be divided into grade I (≥ 90min), grade II (≥ 60min), grade III (≥ 45min) and grade IV (≥ 30min). Fire resistance integrity -- refers to the flame on the back fire surface of the test piece and continues to burn for 10s or more; During the experiment, when the flame or gas of the test piece appears from the holes and other gaps, carry out the ignition test of the cotton pad. If the cotton pad is ignited, it indicates that the test piece has lost its integrity (if the test piece collapses during the experiment, it also indicates that the test piece has lost its integrity).

Fire resistance and thermal insulation -- refers to the temperature rise of single point at the temperature measuring point on the back fire surface of the test piece of 180 ℃ and uniform temperature rise of 140 ℃.

Thermal radiation intensity refers to the critical radiant heat illuminance of 0.42w/cm2 at 3M away from the back fire surface of the test piece, and the critical radiant heat illuminance of 3.35w/cm2 at an interval equal to 1.2 times of its smaller scale (length or width).

3 composition and operation principle of fireproof glass

Composite fireproof glass (or fireproof laminated glass) is made by bonding and compounding two or more single-layer flat glass with intumescent flame retardant cement; The pouring type fireproof glass is made of two or more pieces of single-layer flat glass, which are sealed with frame strips, and then filled with fireproof liquid through the pouring port, cemented and sealed; At room temperature and in the early stage of fire attack, the composite fireproof glass has the same light transmission function and decoration function as the general flat glass; After the fire broke out, with the extension and expansion of the fire, the fire temperature increased, and the composite fireproof glass fireproof interlayer expanded and foamed after heating to form a very thick fireproof insulation layer, which has the effect of fireproof insulation and fireproof separation [2]. However, the composite fireproof glass generally has some problems, such as small bubbles, poor cold resistance and poor light transmittance, which affect its use effect [3].

Thin coated fireproof glass is sprayed with fireproof transparent liquid on the surface of single-layer or multi-layer flat glass substrate, and then made into fireproof glass after drying and curing. When the thin coated fireproof glass is exposed to fire, the fireproof maintenance layer is heated and expanded to form a dense fireproof maintenance layer to maintain the substrate glass and prevent the extension of fire.

According to the structure, fireproof wired glass is divided into wired glass and fireproof wired laminated glass. Wire glass is a kind of glass produced by calendering. When the liquid glass is formed between the calendering rollers, the preheated metal wire or metal mesh is pressed into the glass plate to make the wired glass. Fireproof wire sandwich glass is made by placing metal mesh in the sandwich in the production process of composite fireproof glass. When the wire glass is subjected to external force or breaks in the fire, the glass fragments can still be fixed on the wire or net without falling, which can prevent the flame from penetrating and hinder the extension of the fire. The major defect of the wire glass is the poor heat insulation function. The temperature of the back fire surface is as high as 400 ~ 500 ℃ for more than ten minutes after the fire. Fireproof laminated glass has the advantages of both wired glass and fireproof laminated glass, and some have a long-term prospect of popularization and application. However, the wire glass produced in China is opaque, which can not achieve the light transmission and decoration effect of glass, which affects its popularization and use.

Single piece fireproof glass is to use physical and chemical methods to treat the general glass, modify its appearance, improve the thermal stress function of the glass, and then ensure that it will not crack under the impact of flame or high temperature, so as to prevent the flame from penetrating the fireproof glass and convey the intention of fire. Because of the light weight, transparency and decoration of single fireproof glass, it is used in more and more buildings. However, a single piece of fireproof glass cannot block the thermal radiation of the flame, and can only be tested by class C fireproof glass. This must be considered when it is used as a fireproof partition. Surface treatment method of monolithic fireproof glass

4.1 external stress of fireproof glass

Belby layer and residual stress; After solid data processing, drastic changes in arrangement structure may occur in the surface layer of several microns to more than ten microns. For example, during metal grinding, because the surface is uneven, the contact is actually a point, and its temperature can be much higher than the uniform temperature of the surface. Because the effect time is short, the temperature in this area cools down rapidly after friction, and the atoms have no time to return to the equilibrium position, resulting in a degree of lattice distortion. This distortion changes with depth. In the outer layer, about 5 ~ 10nm, it can form an amorphous state, which is composed of metal and its oxide, that is, belby layer. The belby layer improves the apparent strength of the data. After the surface processing, the berby layer composed of the surface layer of the data has a great residual stress, the data is heated unevenly, the expansion coefficient of each part is different, and the thermal stress will occur in the data when the temperature changes. When the data is loaded, the effect of internal stress and external stress occurs together. If the internal stress is the opposite of the external stress, then this effect will be offset by the external stress. In addition, the compressive stress on the surface of tempered glass can further tighten the small cracks that cause the source of glass cracking, and also improve the mechanical strength of tempered glass.

Article source: fireproof glass http://www.ba-glass.com/