Refractory bricks have very high resistance to high temperatures.Fire bricks or fire clay are the examples for refractory bricks.Refractory bricks are used in kilns, chimneys, boilers etc.In this article, we are discussing the types of refractory bricks.
Types of Refractory bricks
1.Acid Refractory Bricks
Acid Refractory bricks consist of silica bricks and ganister bricks.Silica bricks contain 95 % silica and 5% lime.Ganister bricks are acid refractory bricks consist of 10 percent of clay and 2 percent of lime.Acid refractory bricks are softened only at about high temperature (1800º c).Silica bricks are very hard and it possesses high refractoriness under load.
But these type of acid refractory bricks is not used in rapid temperature changing environment.Because acid refractory bricks have the tendency to spall.So they are not used for the lining of the furnace.Because of rapid temperature changing.
2.Basic Refractory bricks
Basic refractory bricks consist of magnesium bricks and bauxite bricks.Magnesium bricks are 80 percent of magnesia and 15 percent of calcium oxide and 5 percent of silica.Bauxite bricks consist of 85 percent of aluminium oxide and 20 percent of clay.
Basic refractory bricks are highly resisting to corrosion and are used for the lining of furnaces.
3.Neutral Refractory Bricks
Neutral refractory bricks consist of chromite bricks( 50 percent chrome and 30 percent iron ore).The neutral refractory bricks are used in places where acid and basic linings have to be separated.
eg-For lining copper furnace.
These are the types of refractory bricks