What is insulating refractory brick?

Insulating firebricks, also known as soft bricks or IFBs, are used in high temperature applications from 2,000°F (1,093°C) to 3,200°F (1,760°C). The bricks are made from high purity fire clays and other ceramic raw materials according to international standards and are suitable for working in different temperatures and atmospheres up to 3000 degrees Fahrenheit. IFB bricks contain a finely graded organic filler that is fired during the manufacturing process to create a uniform controlled pore structure. This high porosity rate provides excellent insulating properties while contributing to the lightness of the brick.

Insulating bricks are soft and light in weight. They can be easily cut with a hand saw or any other hand tool such as a chisel or even a drill.The color of insulating bricks varies, but usually they range from light brown to white, see pictures. In the air, refractory is the best insulator and that is why insulating refractory bricks have excellent insulating properties. Their bodies are made of small air spaces similar to the honeycomb effect.

What is meant by hard bricks?

Hard bricks, also known as Super Duty or High Alumina, are very hard, dense and durable refractory bricks. Bricks are produced with selected Schmutt bauxite as the main raw material and are fired at 1450-1470 degrees Celsius using an advanced process with strict quality control. These bricks are not self-insulating compared to IFB samples. Special tools such as tile or brick saws are required to cut and shape bricks.It is commonly used in furnaces due to their structural features and because they easily absorb and conduct heat, which allows for the high temperatures required in firing. It is often used as a major component in the construction of large furnaces, chimneys, furnaces, and burner ports—anywhere around a direct flame. Hard bricks are usually used in conjunction with insulating fire bricks to provide an excellent complete solution for refractory applications.

Applications of insulating refractory bricks

Insulation firebrick is used for fireplaces, furnaces, built in homes, businesses and manufacturing facilities. Sometimes referred to as “firebrick,” it is designed to withstand temperatures up to 3,200 degrees Fahrenheit while conducting very little of that heat to provide a higher level of energy efficiency.Insulating firebrick is mostly used in commercial environments, especially in manufacturing facilities where there are thermal, chemical or mechanical stresses. Some of these settings include wood-fired furnaces and furnaces where wear, ash accumulation, or continuous exposure to high temperatures may weaken the structure. In some other cases, such as a furnace that uses electricity or natural gas, highly porous options known as “furnace bricks” are often chosen instead.

Material and durability

A variety of materials can be used to make insulating firebricks, but generally they are made from fireclay or some other type of raw ceramic material. The structure of the pores inside the brick is carefully controlled to create more air pockets during firing. This air absorbs and dissipates heat in applications where bricks are used, so these are very important.When the temperature changes rapidly, the bricks do not flake, and despite the high temperature, they continue their strength and structure for years.

How to make refractory bricks

How to make insulating firebrick depends to a large extent on the materials used. It is fired inside the furnace until it turns into glass, and it may sometimes be glazed depending on how it is used. They are standard sizes for the most part, but they also come in “splits” that are half the standard thickness and are used for lining fireplaces and wood stoves.

Use in high temperature settings

Insulating firebricks used at high temperatures such as steel furnaces are generally made of silica, which can withstand temperatures up to 3000 degrees Fahrenheit. Part of it becomes liquid at this temperature.Primary refractory bricks are used in other environments, especially in wood-burning or coal-burning facilities, to prevent heat transfer to other materials.

Use on low temperature settings

For smaller chimneys and wood stoves, red clay bricks can be used as insulating firebricks. For larger components, bricks composed of magnesium oxide are common in furnaces, while silica is used for the inner lining of furnaces.

There are several standard brick sizes available today and these are suitable for many applications. However, because architecture and technology sometimes use structures where everything is standard, bricks may be created in special shapes that are machined or cemented. It is better to have a final product that has as few connections as possible to increase the life of the installation.They can be created using tapers, tongue and groove cuts, drilled holes, and more based on plans.

Mortars

When installing brick, it is important to find a specially formulated mortar that can retain water while being strong enough to withstand high temperatures. Any joints between the bricks should be properly sealed to extend their life. There are different types of refractory brick mortar, and the type used in each application depends on the brick selected and the temperature it must withstand. Traditional mortar cannot be used to lay this type of brick. In most cases, mortar complements the purchase of bricks.

Insulating firebrick is used worldwide to protect structures from heat and prevent fires in chimneys and furnaces. This device is made of a wide range of materials to suit any type of application required.Physical properties of refractory bricks

Physical properties of refractory bricks

Bulk density: 604 kg / m2

Modulus of rupture: 1.52 MPa

Cold compressive strength: 2.01 MPa

Thermal conductivity 300°C: 0.2 W / m / °C

Thermal conductivity 750°C: 0.28 W / m / °C

Thermal conductivity 1000°C: 0.32 W / m / °C