How to choose the Right Refractory Bricks Material?

What are Refractory Bricks?

Refractory bricks are used in constructions that require high heat resistance, such as furnaces, kilns, and fireplaces. These bricks are capable of withstanding extreme temperatures without melting or deforming, making them essential for heat-intensive applications. Refractory bricks are typically made from materials like silica, alumina, and fireclay.

Their ability to maintain structural integrity at high temperatures is coupled with their low thermal conductivity, which helps in retaining heat within structures. This makes refractory bricks an integral component of energy-efficient heating systems in industrial applications.

Refractory bricks come in various colors, such as yellow, grey, red, and orange. They are widely used in construction due to their strength, long life span, durability, low maintenance, and timeless colors that won’t fade or change. They are composed of %60-96 silica; %2- 36 alumina; and %2-5 lime, alkalis, magnesia, and iron oxide.
Making firebricks is molding clay and then firing it in incredibly hot ovens, leaving us with solid, fireproof bricks that can withstand extreme pressure and conditions. Due to their low thermal conductivity (energy-efficient), these bricks are usually used in lining furnaces, kilns, fireboxes, and fireplaces. Firebrick is a block of refractory ceramic material used in lining furnaces, kilns, fireboxes, and fireplaces.

Types of Refractory Bricks

Many types of refractory bricks can be broken down into even more subtypes, resulting in a wide variety that fulfills different construction needs and can be used for multiple purposes.

1) Basic Refractory Bricks:

Bauxite refractory brick: Bauxite bricks comprise around 85% aluminum oxide and less than 20% clay. They’re also highly corrosion-resistant and are heavily used in lining furnaces.

Magnesite bricks: This variety of refractory bricks consists of more or less than 85% magnesium oxide and an average of less than 35% iron oxide.

Dolomite refractory bricks: Primarily consist of carbonate of calcium and magnesium, which makes these bricks more waterproof than the other types. Dolomite bricks are the cheaper substitute for magnesia bricks, and they’re usually used in manufacturing the lining of converters and ladles and constructing the shaft and rotary kilns of the lime and cement industry.

2) Acid refractory bricks

Silica bricks: 95 – 97% silica, 1 – 2% lime. Refractory bricks made of fireclay or kaolin are pretty common. Still, silica bricks have high integrity and can withstand extreme temperatures for prolonged periods with no appreciable damage, and that’s why we use them to make furnaces that remain hot constantly.

Ganister bricks: Refractory bricks made of the complex, colored stone named ganister. Ganister bricks consist of almost 90% percent of silica (ganister), along with around 10% clay and lime. They’re usually used in lining furnaces that produce siliceous and acidic slag steel because they are resistant to the damage caused by them,  and they’re also commonly used in making cooking ovens.

3) Neutral Refractory Bricks

• Chromium brick (50% Chrome iron ore)

• Carborundum (temperature of 21900 degree Celsius)

• Chrome magnesite brick

• Spinal brick (Alumina and magnesia have equal proportion)

• Forsterite Brick

  
  

How to choose the Right Refractory Bricks Material？

Factors to consider when choosing a specific refractory brick material
Chemical composition: Each type of refractory brick is designed to handle specific chemical compositions. Ensure that the material you choose is suitable for your application’s chemical composition.
Thermal conductivity: Thermal conductivity measures the rate at which heat travels through a material. If your application requires efficient heat transfer, consider choosing a brick with high thermal conductivity.
Abrasion resistance: Abrasion resistance is essential for applications that involve material flow or high mechanical impact. If your application requires abrasion resistance, consider choosing a firebrick with high hardness.
Porosity: Porosity affects the brick’s ability to withstand thermal shock. If your application involves rapid temperature changes, consider choosing a fireproof brick with low porosity.

Comparison of The Different Types of Refractory Bricks

Strengths and weaknesses: Each type of refractory brick has its own strengths and weaknesses, depending on the application. For example, firebricks have excellent thermal shock resistance, but poor abrasion resistance.
Costs: The costs of different refractory firebrick materials vary depending on the raw materials used and the manufacturing process. Consider your budget when choosing a specific type of refractory brick.

A. Firebricks: Firebricks are made from refractory clay and have excellent thermal shock resistance. They are commonly used in high-temperature applications such as furnace linings and chimney linings.
B. High Alumina Bricks: High alumina bricks are made from alumina and other refractory materials, and are known for their excellent strength and abrasion resistance. They are often used in steelmaking and other heavy industry applications.
C. Silica Bricks: Silica bricks are made from silica and are resistant to acidic environments. They are often used in the glass and ceramics industries.
D. Mullite Bricks: Mullite bricks are made from mullite, a type of mineral that is known for its high-temperature resistance. They are often used in the production of iron and steel.
E. Clay Bricks: Clay bricks are made from fire clay and are often used in low-temperature applications such as fireplace linings and chimneys.
F. Magnesia Bricks: Magnesia bricks are made from magnesia and are highly resistant to alkaline environments. They are often used in the production of cement and lime.
G. AZS Bricks: AZS fire bricks are made from alumina, zirconia, and silica, and are highly resistant to high temperatures and thermal shock. They are often used in the glass and steel industries.

Simply you may ask our expert in TKF Bricks for help to choose the best suitable refractory bricks for your application. Welcome to contact us!