Lightweight insulation brick is a kind of heat insulation refractory material, which refers to refractory bricks with high porosity, low bulk density and low thermal conductivity. Lightweight insulation bricks are characterized by a porous structure (the porosity is generally 40-85%) and high thermal insulation. There are many classification methods for lightweight insulation bricks
Lightweight refractory bricks with a bulk density of 0.4~1.3g/cm³; ultralight refractory bricks with a bulk density of less than 0.4g/cm³
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Use temperature 600~900C for low temperature insulation material; 900~1200C for medium temperature insulation material; over 1200C for high temperature insulation material.
One is shaped lightweight thermal insulation bricks, including clay thermal insulation refractory bricks, high alumina thermal insulation refractory bricks, siliceous refractory bricks, and some pure oxide lightweight refractory bricks; the other is unshaped lightweight thermal insulation bricks , Such as lightweight refractory concrete, etc.
The disadvantages of lightweight refractory bricks are large porosity, loose structure and poor slag resistance. The molten slag quickly penetrates into the pores of the refractory brick body, causing it to break, and cannot be used for direct contact with molten slag and liquid metal. It has low mechanical strength, poor wear resistance and unstable thermal stability. It cannot be used for load-bearing structures, nor should it be used for parts that are in contact with furnace materials and are severely worn.
