Clay bricks and high alumina bricks are types of refractory bricks used for heat resistance and fireproofing applications, yet similar in many ways to each other. Although there are certain similarities, there is no definite differentiation. Each can only be used according to certain requirements - and we hope that our article's second half will help explain those specifications as well as differences between them and other types.

1. Clay bricks should meet one standard. They must contain sufficient Al2O3 to meet fire resistance standards so they work reliably under high temperatures.

2. 2 and Fe2O3 have low requirements to limit carbon black deposition and prevent it from reacting with SiO2 to form low melting point substances, which would reduce fire resistance.

3. Blast furnace masonry operates under extreme temperatures and pressures, and its starting temperature for load softening can be relatively high.

4. It is essential that the refire shrinkage be kept to an absolute minimum in order to prevent cracking during high-temperature operations and stop slag, iron and other sediments from penetrating into brick joints and damaging refractory masonry.

Comparing high alumina bricks with clay bricks:

1.Color

The main differences between high-alumina bricks and clay bricks lie in color; high-alumina bricks typically feature beige or white hues while higher quality varieties feature smooth surfaces with blue luster finishes compared to yellow or dark yellow shades found on clay bricks.

2. Weight

High-alumina bricks weigh more than 3.7kg; high-grade high-alumina bricks may reach approximately 5kg in weight, while clay bricks usually weight under 3.65kg.

3. Classification

High alumina bricks can be classified by their Al2O3 content into four groups, as follows: ultra-high alumina bricks containing more than 80% Al2O3, first-level high-alumina bricks with an Al2O3 content between 75%-80%, second-level high-aluminum bricks with 60%-75% Al2O3, aluminum bricks as third grade high-alumina with 48%-60% content as well as clay bricks that fall in these categories; national standard, low creep and low porosity clay bricks may all fall under these categories of classification.

4. Features. Refractoriness Temperature. Refractoriness temperature for high-alumina bricks ranges between 16801650 degrees C, making them an excellent refractory material. Clay bricks generally offer lower fireproofing properties than their high-alumina counterparts, however their fire resistance remains the same at 1680-1650degC.

Load softening temperature for high alumina bricks typically ranges between 0050, while that for clay bricks typically falls within 5050.

As far as slag resistance goes, high alumina bricks and clay bricks tend to have poor acid resistance; their resistance against acid slag being stronger than that against alkali slags. SiO2 content increases along with acid resistance.

Thermal Shock Resistance. Clay bricks cooled at 850degC take three to five times longer to cool than their ordinary counterparts, and three-five times longer when cooling at 10degC than those made of ordinary material. By applying ZrO2, ZrO2 bricks can enhance thermal shock resistance - such as drop resistance.

5. Application

Clay bricks can be used without special requirements when building brick walls, with operating temperatures lower than 00. They are commonly found in blast furnaces, hot blast furnaces, iron-making furnaces, open hearth furnaces, electric furnaces and low temperature glass furnaces as well as ladles pouring systems heating furnaces heat treatment furnaces combustion chambers flues and chimneys.