With over 20 years of experience, we at RS Refractory are dedicated to providing top-quality refractory materials. In this article, we explore common damage phenomena in glass kiln refractories, helping you identify and prevent potential issues in your kiln operations.
Types of Damage
1. Erosion
Erosion is caused by high temperatures, flame, raw material powder, atmosphere, gas flow, and liquid flow within the kiln. These factors severely impact the refractory materials, reducing the lifespan of the kiln. Erosion can occur at various parts of the kiln, including the front wall, feed port, melting area, pool wall, and regenerator grids.
- Raw Material Powder: Alkaline vapor from high-temperature evaporation can erode refractories like silica bricks, leading to issues such as "mouse holes" inside the bricks and nepheline formation in the grids.
- Glass Liquid: Though less severe than raw material powder, the glass liquid dissolves free SiO₂ in the refractory, forming a protective layer that can eventually wear down.
2. Thermal Damage
Thermal damage occurs due to prolonged exposure to high temperatures, causing refractories to melt or soften. Overheating specific kiln parts or using refractories with insufficient refractoriness can result in severe thermal damage.
Key Areas Affected:
- Burners and Arches: High temperatures in these areas can lead to material deformation.
- Heat Exchanger Chambers: Often susceptible to high-temperature damage, leading to structural instability.
Cracking typically happens during kiln heating when temperature gradients within refractory bricks create mechanical stress. Rapid temperature increases exceeding the material's strength can cause cracks or even break the bricks.
Prevention:
- Controlled Heating: Following a pre-determined heating curve is essential to minimize cracking risks.
- Material Selection: Using materials with high mechanical strength and low expansion rates can reduce the likelihood of cracking.
4. Wear
Wear occurs when the glass liquid flows over refractory surfaces, eroding them over time. This mechanical wear is evident at the glass liquid surface and in areas with turbulent flow.
Prevention:
- Refractory Selection: Using high-durability refractories in high-wear areas can prolong the lifespan of kiln components.
5. Chemical Erosion
Chemical erosion involves the reaction between molten glass and refractories, particularly affecting pool wall bricks. High-alkali and borosilicate glasses can intensify chemical erosion.
Key Factors:
- Volatile Compounds: Combustion products and raw material volatiles can react with refractories, accelerating erosion.
- Glass Composition: Glasses containing compounds like boron and aluminum are particularly aggressive towards refractories.
6. Physical Erosion
Physical erosion primarily results from the scouring action of molten glass and the weight stress on the refractory materials. Strong glass flows and high kiln structures exacerbate this issue, potentially leading to grid brick collapse.
Prevention:
- Structural Integrity: Ensuring robust construction and using high-strength refractories can mitigate physical erosion.
Conclusion
By understanding these common damage phenomena, you can better maintain your glass kiln and extend the life of your refractory materials. At RS Refractory, we offer a wide range of high-quality refractory bricks designed to withstand the rigorous demands of glass kiln operations. Explore our products here and contact us for personalized recommendations and quotes.
Contact Us for More Information
For further inquiries and customized solutions, feel free to reach out to us. Our team of experts is ready to assist you with all your refractory needs.
