Types of refractory bricks and properties to be met

Refractory bricks are used as raw materials in a variety of high-grade natural environments. The common refractory bricks are silica bricks, clay bricks, high-aluminum refractory bricks, and corundum refractory bricks. The main uses of each brick are all different. Refractory bricks need to consider the characteristics of fire resistance, high-grade structure, heat resistance, slag resistance, stable high-grade volume, etc. The following refractory brick manufacturers will introduce them in detail.

Types and main uses of refractory bricks

1. Silica brick

It refers to refractory bricks containing more than SiO293%, which is a key type of acid-alkali refractory bricks. It is mainly used for wall-building coke ovens, as well as for the vaults and other load positions of insulated industrial kilns for various laminated glass, porcelain, carbon factory calciners, refractory bricks, and is also used in high load positions of hot air boilers., but it is not suitable for use in heat-insulating machinery and equipment below 600 ° C and with large fluctuations in temperature.

2, clay brick

Clay bricks are mainly composed of zirconium corundum (25%~ 50%), laminated glass phase (25%~ 60%) and square quartz and quartz stone (up to 30%). Generally, hard clay is used as raw material, which is calcined and perfected in advance, and then matched with soft plastic clay, which is desulfurized by semi-dry method or formed by plastic method. The clay brick product can be fired at 1300~ 1400 C. It is also possible to add a small amount of fusion agents such as sodium silicate and concrete to make unburned products and amorphous raw materials. It is a common refractory brick in ironmaking blast furnaces, hot air boilers, heat treatment furnaces, driving force heating furnaces, lime kilns, cement rotary kilns, porcelain and refractory brick kilns.

3, high aluminum refractory brick

The minerals of high-alumina refractory bricks are composed of steel jade, zirconium corundum and laminated glass phases. Its composition lies in the AL2O3/SiO2 ratio and the type and total number of residues. The grade of refractory bricks can be divided according to the AL2O3 composition. The raw materials are high alumina vanadium soil and sillimanite pure natural iron ore, which are also mixed with fused pipe fittings steel jade, calcined aluminum oxide to form zirconium corundum, and cement clinker calcined with aluminum oxide and clay according to different proportions. It should be produced by calcination. But there are also molten bricks, molten bricks, unfired and amorphous refractory bricks. High alumina refractory bricks are widely used in the iron and steel industry, metal industry production and other industrial production.

4, corundum refractory brick

Corundum brick refers to a refractory brick with AL2O3 composition of not less than 90% and steel and jade as the key phase. It can be divided into calcined corundum brick and fused pipe fitting corundum brick.

Second, the characteristics of refractory bricks need to be considered

1, high fire resistance

The heating temperature of contemporary metallurgical industry and other industrial furnaces is generally between 1000-1800 ° C. Refractory bricks should have the characteristics of not easy to melt under high efficiency.

2. High-grade structure has high compressive strength

Refractory bricks should not only have a high degree of melting, but also have no softening deformation and collapse under the load of furnace building or other mechanical equipment vibration.

3, good heat resistance

In the operation process of metallurgical industrial furnaces and other industrial production industrial furnaces, due to drastic changes in temperature, the temperature of each part of the raw materials is not uniform, and the earth stress will cause the structure to crack and fall off. Therefore, refractory bricks need to have the ability to resist such damage.