High-alumina lightweight brick is commonly known as high-aluminum heat insulating brick. Alumina content is 48% or more, lightweight refractory material mainly composed of mullite and corundum or glass phase. Its essential function is heat insulation, under normal operation usually do not contact directly with the temperature of the furnace. It is a kind of refractory brick, which is close to the furnace wall and has the function of heat insulation and heat preservation.
The bulk density is 0.6-1.35 g / cm3; Porosity is 66% -73%; compressive strength is 1-8MPa. High alumina bricks are produced with grinded bauxite clinker and a small amount of clay, through gas generating method and foaming method, the mud is poured into the shape of brick, then bricks are formed by sintering under temperature 1300～1500℃.
Sometimes industrial alumina bauxite may also be used in place of some alumina clinker. High alumina bricks are used for lining and heat insulation layer of the kiln, as well as the areas where there is no intense high temperature melt material erosion. When directly contact with flame, the surface contact temperature shall not be over 1350C.
CCEWOOL ® LHA Series insulating brick |
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Item |
LHA10 |
LHA09 |
LHA08 |
LHA07 |
LHA06 |
LHA05 |
LHA04 |
AI2O3 |
≥48% |
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Fe2O3 |
≤2% |
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Density (g/cm3) |
1.0 |
0.9 |
0.8 |
0.7 |
0.6 |
0.5 |
0.4 |
Compressive strength (MPa) |
4 |
3.5 |
3.0 |
2.5 |
2.0 |
1.5 |
0.8 |
Linear change Cx12h (%)≤ |
1400 |
1400 |
1400 |
1350 |
1350 |
1250 |
1250 |
Thermal conductivity W/(m.k) |
0.5 |
0.45 |
0.35 |
0.35 |
0.3 |
0.25 |
0.2 |
