There are three main types of magnesia chrome bricks produced for industrial purposes. Typically these bricks have found great use in environments where pressure and heat resistance are crucial properties to have, for instance in furnaces. Herein are the three types of bricks, their specific properties, and the environment in which they are used.
1. Sintered Magnesia Chrome Bricks – Sintered magnesia chrome bricks are made of sintered magnesia and chrome ore. The materials are sintered at high temperatures to yield magnesia bricks with temperature resistance. Aside from the strong thermal resistance of the bricks, magnesia bricks also have high bulk densities.
The above qualities make the bricks prime for use in cement rotary kilns, permanent lining in steel furnaces, glass kiln regenerators, and as permanent lining in refining ladle.
2.Direct-Bonded Magnesia Chrome Bricks – The manufacture of direct-bonded magnesia bricks uses high purity magnesia sand and lower impurity chrome ore as the raw materials. The manufacturing process involves heating the material to temperatures above 1700℃, resulting in magnesia bricks that have a high resistance to temperatures.
Additionally, the brick attains strong slag resistance and a strong resistance to corrosions, especially corrosion of the cement clinker. Owing to these characteristics, direct-bonded magnesia chrome bricks are used in rotary kilns, non-ferrous metal furnaces, and electric arc furnaces.
3.Rebonded Magnesia Chrome Brick – Rebonded magnesia chrome bricks use all or partial electric melting sand as the main raw material. The manufacturing process involves the molding under high pressure and high temperatures to give rise to thermal resistance.
Rebonded magnesia chrome bricks are widely used in VOD furnaces, AOD furnaces, and in snorkels of RH furnaces. These bricks are also used in non-ferrous metallurgical furnaces owing to good binding properties and the high strength of the bricks.
There is also another type of types of magnesia chrome brick closely related to the reboned magnesia chrome bricks – the semi-rebonded bricks.