Comparison of Physical and Chemical Indicators of Different Types of Refractory Bricks

Due to different operating departments, even in different parts of the same kiln, the working conditions are not the same. Therefore, the requirements for refractory bricks are also different. Based on the general working conditions of ordinary industrial furnaces, the following requirements are put forward for the performance of refractory bricks:

1. Resist high-temperature heat load, no softening, no melting. Refractory bricks are required to have a relatively high degree of refractoriness.

2. Resist the effect of high-temperature heat load, the volume does not shrink and only expands uniformly. The material is required to have high volume stability, small residual shrinkage and residual expansion, no crystal transformation, and serious volume effect.

3. Resist the joint action of high-temperature thermal load and heavy load, without loss of strength, creep, and collapse. The material is required to have relatively high normal temperature strength and high-temperature hot state strength, high load softening temperature, and high creep resistance.

4. Resist sharp temperature changes or uneven heating, no cracking, no peeling off. The material is required to have good thermal shock resistance.

5. Resist the chemical erosion of molten liquid, dust, and gas, no deterioration, no erosion. The material is required to have good slag resistance.

6. Resist the impact, impact, and abrasion of flame, charge, and dust, and the surface will not wear out.

7. The material is required to have relatively high compactness and wear resistance at room temperature and high temperature.

8. Resist the influence of high-temperature vacuum operation and atmosphere change, with no volatilization, and no damage. Materials are required to have low vapor pressure and high chemical stability.

In addition, in order to ensure the overall quality of the structure or lining made of block refractory bricks. The slag resistance and air tightness are good, and it is convenient for construction. It also requires the material to be neat in shape, and accurate in size, to ensure a certain tolerance, and to eliminate unacceptable defects. In order to withstand the impact during transportation and the possible mechanical vibration and extrusion, the material must have a relatively high room temperature strength. For some special requirements, sometimes its thermal conductivity and electrical conductivity should be considered.

It should be noted that although the above points can be used as the basis for evaluating the quality of refractory bricks, no refractory brick can fully meet all the above requirements. When selecting or evaluating refractory bricks, the outstanding characteristics of the material must be adapted to the conditions of use and made the best use of them. At the same time, economic accounting is also considered.