How to Choose Silica Bricks

1. Prioritize Core Components and Indicators

The core value of silica bricks lies in their high-temperature resistance. Key components and indicators directly determine their performance, so it’s crucial to carefully verify product testing reports.

SiO₂ Content: This is the core of silica bricks’ high-temperature resistance. High-quality silica bricks should have a SiO₂ content ≥93%. Higher content results in stronger resistance to acid erosion and higher temperature resistance, so making them less prone to deformation over long-term use.

Load Softening Temperature: This indicator determines the maximum operating temperature a silica brick can withstand. High-quality silica bricks should have a load softening temperature ≥1620℃, in order to they won’t soften or collapse under load in high-temperature kilns and similar environments.

Bulk Density and Apparent Porosity: It’s recommended to choose products with a bulk density ≥1.8g/cm³, and an apparent porosity controlled between 16%-22%. Because Silica bricks with high density and moderate porosity have a more compact structure, resulting in better thermal conductivity and impact resistance.

2. Check Appearance and Dimensional Accuracy

Appearance Defects: The surface must be flat, free of obvious cracks (especially through cracks), missing corners, chipped edges, and large areas of discolored spots. Because micro-cracks may propagate rapidly at high temperatures, leading to brick breakage.

Dimensional Deviation: Measure the length, width, and height of the bricks using a tape measure or calipers. Deviations must conform to industry standards (generally ≤ ±1mm).

3. Matching Specific Application Scenarios

Glass Kilns: Silica bricks with strong corrosion resistance should be selected, with a focus on the “resistance to molten glass erosion” index. High brick flatness is also required to reduce the risk of molten glass penetration.

Coke Ovens: Silica bricks for coke ovens need to balance high-temperature resistance and thermal shock resistance. It is recommended to choose products with stable coefficients of thermal expansion to avoid cracking caused by prolonged temperature fluctuations.

Other high-temperature equipment (such as ceramic kilns and electric furnaces): If the equipment does not have a particularly corrosive environment, priority should be given to load softening temperature and bulk density, ensuring basic high-temperature resistance.

4. Verify Brand and Quality Assurance

Choose a reputable manufacturer: Prioritize manufacturers with over 5 years of production experience and complete testing equipment.

Request testing reports:  Focus on verifying key indicators such as SiO₂ content and load softening temperature to ensure consistency with advertised specifications.

Confirm after-sales service: Inquire about the product’s shelf life, return and exchange policy, and masonry guidance services. Some manufacturers offer technical support to help optimize masonry plans and extend the lifespan of the silica bricks.