High mechanical strength refractory brick for kiln
High alumina refractory brick
High-alumina refractory bricks are high-quality refractory materials. They usually have high refractoriness and are usually used in ultra-high temperature environments, such as industrial furnaces, furnaces, incinerators, etc.
What is high alumina refractory brick?
The high-alumina refractory brick here in China is a kind of aluminum silicate refractory material, in which the alumina content exceeds 48%. After grinding and mixing, bauxite and other materials containing a high proportion of alumina are shaped, and then sintered at high temperatures to produce high-alumina refractory bricks.
Those high-alumina refractory bricks can be used to build electric arc furnaces, glass kilns, cement rotary kilns, etc.
Item |
HA60 |
HA70 |
HA75 |
HA80 |
AL2O3(%) |
≥60 |
≥70 |
≥75 |
≥80 |
SIO2(%) |
32 |
22 |
20 |
≥18 |
Fe2O3(%) |
≤2.5 |
≤2.0 |
≤1.8 |
≤1.8 |
Refractoriness °C |
≥1750 |
≥1770 |
≥1780 |
≥1790 |
Bulk density,g/cm3 |
2.35-2.4 |
2.45-2.5 |
2.5-2.55 |
2.55-2.6 |
Softening temperature under load |
≥1450 |
≥1510 |
≥1520 |
≥1530 |
Apparent porosity,% |
≤24 |
≤23 |
≤22 |
≤21 |
Cold Crushing strength Mpa |
≥45 |
≥50 |
≥54 |
≥60 |
Advantages of high alumina refractory bricks
The high alumina refractory bricks produced by our company have many advantages. Low creep and high refractoriness under load are outstanding advantages of refractory products. Ultra-fine bauxite, corundum corundum, and mullite corundum are the main raw materials for high-alumina refractory bricks. So that the brick has a strong resistance to corrosion, which is caused by iron slag, harmful air and other corrosion generated in the kiln. They also have good thermal stability. These bricks are high-quality masonry products for medium and large-scale hot blast stoves.
Classification of high alumina refractory bricks
High alumina refractory bricks are classified according to the content of alumina (Al 2 O 3). Common types of high alumina refractory bricks include those containing 48%, 55%, 60%, 65%, 73%, 75% and 80% Al 2 O 3. Those bricks containing less than 55% Al 2 O 3 are refractory bricks, which are a neutral refractory brick material. This type of brick is made of bauxite and other materials with high alumina content. Moreover, refractory products have high thermal stability. They are always used as linings for glass melting furnaces, cement rotary kilns and electric arc furnaces.
There are also bricks with high refractoriness, low creep and low porosity under load. Different proportions of ingredients lead to different types of bricks.
The difference between high alumina bricks and refractory bricks is far greater than the difference in content. They have similar manufacturing processes, but the composition of high alumina refractory bricks is mixed with more clay, and the content is between 90% and 95%. The firing temperature of high alumina is also much higher. In actual use, Class I and Class II high alumina refractory bricks are usually used in blast furnaces, tunnel kilns, furnace roofs, reverberation furnaces and rotary kilns with temperatures between 1500-1600°C.