Applications of Ceramic Fiber Blanket in the Optical Glass Annealing Industry

Ceramic fiber blanket plays an essential role in optical glass annealing, serving as the primary refractory and thermal-insulation lining in annealing furnaces. Optical glass requires precise and uniform temperature control to prevent internal stress, distortion, or optical defects, and ceramic fiber blanket provides the stable thermal environment needed for these high-precision processes.

Key Advantages

Ceramic fiber blanket is widely adopted in optical glass annealing equipment, and HTCC high-temperature atmosphere pusher kilns—due to its comprehensive performance benefits:

• Low thermal conductivity and good insulation: It effectively reduces heat loss and ensures a uniform temperature field inside the annealing chamber.
• Excellent chemical stability, nonflammable: Resistant to oxidation and fumes released during glass heating, maintaining long-term stability.
• Good tensile strength and springiness: Its flexible and elastic structure ensures reliable sealing and compensation in joints or moving areas.
• Excellent performance of soundproofing, good obstructing and resistance to heat-shock: It withstands rapid temperature changes without cracking or structural degradation.
• Low heat capacity: Enables faster heating and cooling, ensuring accurate control of the required annealing temperature curves.

Main Application Areas

1. Furnace Lining Insulation
Ceramic fiber blanket is commonly applied on furnace walls, top covers, and backing layers. Multiple layers are often installed in combination with fiber boards to form a sealed, energy-efficient insulation system. This helps maintain temperature uniformity (typically within ±2–3 °C), which is crucial for preventing thermal stress in optical glass.

2. Sealing of Furnace Doors and Openings
Its flexibility allows the blanket to be used for sealing furnace doors, peepholes, and structural gaps. This prevents cold air intrusion and stabilizes the annealing curve, ensuring consistent product quality.

3. Thermal Zoning and Partitioning
In annealing furnaces used for optical glass, precise control of cooling zones is critical. Ceramic fiber blanket is used as a thermal barrier between high- and low-temperature zones, helping achieve controlled cooling rates.

Material Selection & Installation Notes

• Temperature Range:
  • Standard optical glass annealing (≤1472 °F / 800 °C): standard 2300 °F (1260 °C) grade blanket.
• Construction Recommendations:
  • Use staggered multilayer structures to eliminate thermal bridges.
  • Combine blanket with fiber boards for improved rigidity and insulation.
  • Ensure proper compression at joints to maintain sealing performance.

Conclusion

Ceramic fiber blanket is a high-performance insulation and sealing material indispensable in optical glass annealing. Its low thermal conductivity, excellent chemical stability, nonflammable characteristics, and resistance to thermal shock help maintain precise temperature control while reducing energy consumption.
Ceramic fiber blankets significantly enhance furnace efficiency, stability, and product quality in modern glass processing.