How to choose the appropriate refractory bricks?

Refractory bricks, also known as refractory fire bricks, are usually fired in kilns during the process of manufacture and thus possess the property of thermal-resistant. They are commonly used in a variety of fields. However, as different applications have different requirements for their materials, there are various types of dense refractory bricks designed specifically for diverse purposes. Therefore, when going shopping, we might wonder which type of refractory fire bricks to choose. Here are some tips to help you decide.

-        Types distinguished by their properties

-        Types distinguished by their shapes and colors

-        Choose your bricks depending on your intentions

Types distinguished by their properties

Refractory fire bricks have chemical content, therefore different chemical compositions can lead to various properties.

Medium duty refractory bricks contain about 35% alumina and 50% silica. They can be heat up quickly, thus they are comparatively more efficient at conducting heat than other types of refractory fire bricks.

Compared with medium duty bricks, high duty refractory bricks are able to endure higher temperature (more than 1500F). They have very high alumina content and exhibit excellent properties in thermal resistance and corrosion resistance.

When it comes to high alumina refractory bricks, we generally refer to refractory bricks that contain more than 48% Al2O3 in their content. They can be further divided into more types: if the refractory fire brick has 48% - 60% Al2O3 content, it should be labelled as Grade III high alumina refractory brick. If it has 60% - 75% Al2O3 content, it is Grade II. And if the Al2O3 content is more than 75%, it is Grade I. With more Al2O3 in content, the refractory brick will show better ability in chemical resistance.

Types distinguished by their shapes and colors

We can also use shape as the criterion to differentiate refractory bricks. There are mainly three types. The first one is ordinary type, the most widely used type. Refractory bricks with no concave corners are included in this type. Another type is special shape type which is a new type of refractory fire bricks and are widely used in recent years. This kind of bricks roughly have three concave corners. The last one is standard type which is usually utilized in building common furnaces.

Also, different chemical composition will display different colors in refractory bricks. To be more specific, yellow or dark yellow refractory bricks usually belongs to clay bricks. Those with a relatively light color or in white are high alumina refractory bricks.

Choose your bricks depending on your intentions

To choose the appropriate refractory fire bricks, we have to first identify our applications. For example, if it is for domestic use such as cooking and baking, medium duty brick will be a great choice. But if the brick is going to be used in a professional application (e.g. industrial environment that has continual high heat), we should choose high duty brick. For those areas that require high resistance to chemical attack, high alumina refractory bricks are more suitable. Besides, the size and color of bricks should also be taken into account.