Which kind of refractory brick should be used for the wall of the glass kiln?
For the walls of a glass kiln, the most commonly used refractory brick is fused cast AZS (alumina-zirconia-silica) brick. AZS brick is a high-performance refractory material that is well-suited for the harsh and demanding conditions inside a glass kiln. It is composed of approximately 40-50% alumina (Al2O3), 30-40% zirconia (ZrO2), and 15-25% silica (SiO2), which gives it exceptional properties such as:
High Temperature Resistance: AZS bricks can withstand extremely high temperatures typically encountered in glassmaking processes, making them suitable for both glass melting and glass refining zones.
Resistance to Glass Corrosion: The combination of alumina and zirconia in AZS bricks provides excellent resistance to the corrosive effects of molten glass, alkali vapors, and other glass-making chemicals.
Low Thermal Expansion: AZS bricks have relatively low thermal expansion properties, which helps prevent thermal shock and cracking during rapid temperature changes in the kiln.
High Mechanical Strength: They have good mechanical strength and can withstand the stresses and loads imposed during kiln operation.
Minimal Contamination: AZS bricks are known for their low potential to contaminate the glass, which is essential for maintaining glass quality and purity.
Good Thermal Insulation: Though not as insulating as specialized insulating bricks, AZS bricks still provide some level of thermal insulation to conserve energy.
It's important to note that while fused cast AZS bricks are widely used for the walls of glass kilns, different areas of the kiln may require different types of refractory bricks or specialized coatings based on their specific operating conditions.
AZS bricks are available in different grades, each designed to match the requirements of particular glass types and manufacturing processes. Proper installation and maintenance are also essential to ensure the longevity and efficiency of the refractory lining in the glass kiln. Consulting with refractory experts or manufacturers with experience in glass kilns can help ensure the selection of the most suitable materials for your specific application.