The use of clay bricks in China has a long history. Clay bricks made from refractory clay as the main raw material are called ordinary clay bricks, and clay bricks made from burnt gemstone clinker as the main raw material with a porosity below 17% are called low porosity clay bricks.

Low porosity clay bricks are made from low alumina mullite as the main raw material, which is formed under high pressure and sintered at high temperature. The main mineral composition is mullite phase, and the product has excellent high-temperature physical properties and chemical erosion resistance.

Low porosity clay bricks have good stability, no sudden changes in erosion degree, and their lifespan is increased by 2 to 3 times compared to ordinary clay bricks. The thermal conductivity, specific heat, and solubility are 2 times, 10%, and 40% higher than ordinary clay bricks, respectively. The thermal storage capacity is 50% to 60% higher than ordinary clay bricks, which can improve the thermal efficiency of the kiln.

The characteristics of low porosity clay bricks include:

1. The air outlet hole rate is low, ranging from 13 to 15%;

2. The load softening temperature is around 1472 ℃;

3. High room temperature compressive strength, generally around 100MPa;

4. Good high-temperature volume stability and wear resistance;

5. Good resistance to penetration and erosion.

Low porosity clay bricks, as excellent clay refractory brick products, are often used in environments with chemical erosion and high temperature fluctuations, such as steel, glass, chemical and other industries. The effect is quite obvious in the use of glass hot rooms and hot metal cans.