Refractory brick is a type of brick that is produced from porcelain and refractory soils and has a dense and delicate molecular structure. And the method of production of this type of brick is that first it grinds the stones and then it turns into soft soil and after 3 days of baking in the oven, it is made at a temperature above 1500 degrees Celsius. As the name implies, this brick with its high thermal resistance is widely used in furnaces and pans and industrial insulation. Of course, the usual type is also used today in the brick facades of buildings.
Refractory brick is also a type of building material that is commonly used for facades of buildings and structures. Due to the new style of construction, refractory bricks are used as the facade of the building. The raw materials for making refractory bricks are refractory clay and in general this type of clay is found in the country's mines because it has a high quality. Refractory bricks have different sizes, the most common size of which is 31 * 7 - 26 * 5/5.
Refractory brick ingredients
The base materials of refractory bricks are very special mineral minerals and mineral shells that are refractory. That is, they have a high temperature resistance. The raw materials for the production of refractory bricks are called refractory materials, which are usually ceramic and other metal materials that can be stable at high temperatures. Refractory materials must be able to maintain the desired physical and chemical properties at high temperatures and operating conditions. There are different types of refractory bricks, depending on the type of material used in their composition, they can withstand a wide range. Until the 1960s, carbon and refractory soil were used to cover kilns, but today, they are used in the interior lining of kilns by making various types of refractory bricks.
Types of refractory bricks
These bricks have different types, which are mentioned below:
Silica brick
Bricks that are made of siliceous soil are called silica bricks. Of course, siliceous soils are also called cortisite, whose constituents include very large amounts of silicon oxide, and the rest are calcium oxide, titanium oxide and iron oxide, which use pure quartz to make this compound. This type of refractory bricks is used for the inner lining of steel furnaces. Even silica refractory bricks are used in the production of glass, ceramics as well as coke ovens, because these types of bricks have a high thermal conductivity in impermeability to gases.
Silica bricks are baked at a temperature of 1420 to 1480 ° C with a controlled firing curve. These bricks will have 4 to 5% linear expansion during their firing, which is caused by the phase change of raw materials during firing.
Special refractory bricks
As the name implies, this type of brick has a high degree of resistance to heat and is generally stronger than ordinary bricks. In making refractory bricks, a kind of porcelain or ceramic and refractory clay are used. Refractory bricks are denser than clay bricks and their firing temperature is about 1500 degrees Celsius. These bricks are a type of refractory bricks that are made of intermediate metals and have special applications in industry.
Special types of refractory bricks are: Chromium oxide refractory brick - Corundum
This type of special refractory brick contains 5 to 10% of chromium oxide one and two, which is mixed with 90 to 95% of aluminum oxide and 5 to 10% of chromium oxide. This type of refractory brick is resistant to alkaline materials and as mentioned earlier, this special refractory brick is used for the inner coating of metal melting furnaces. Its main application is in steel blast furnaces!
Zirconium refractory brick
This special refractory brick uses a combination of natural zirconium sulfate, a small amount of alumina and quartz. Zirconium refractory bricks are used in the construction of furnaces that require very high heat. Zirconium or Zr2O metal has a very high resistance to heat and for this reason it is used in aluminum smelting furnaces, molten glass tank furnaces, nuclear reactors, metal smelting plants and in general in steel and metal smelting industries.
Chrome oxide refractory brick
This special refractory brick is widely used in the glass industry. In making this type of refractory brick, 90 to 95% of chromium oxide or Cr2O3 is used and this brick has a high heat resistance, so it is mostly used in aluminum smelting furnace and molten glass furnace. This type is used in the manufacture of glass paste kilns.
Aluminum brick
Special aluminum refractory bricks contain a large amount of aluminum or AL2O3 and are baked at a temperature of about 1750 ° C. This brick contains more than 70% alumina and this has increased its resistance to heat and alkalis. The inner covering of metal and iron smelting furnaces and large glassworks is used. This brick is also used in the construction of the inner wall of cement and glass furnaces.
Special alkali refractory bricks
Alkaline refractory bricks are made from a combination of silicon oxide and magnesium oxide. This special refractory brick is used to cover the inner wall of steel production furnaces, cement production furnaces, the upper wall of glass smelting furnaces and non-metallic industries.
Buyers should consider the following points to choose the best and most suitable refractory brick in the market:
The standard for water absorption in bricks is between 6 and 18 percent.
The convexity and concavity of refractory bricks should not be complicated.
Dimension tolerance (smallest size and largest standard size).
Soluble salts in bricks should not be more than 6%, while in refractory bricks less than