Ceramic Fiber Blanket Temperature Grades: Classification vs. Working Temperature

Ceramic fiber blankets are widely applied in industrial furnaces, kilns, petrochemical systems, and high-temperature insulation projects due to their lightweight structure, low thermal conductivity, and excellent heat resistance.

One of the most common misunderstandings in ceramic fiber blanket selection is confusing classification temperature with maximum continuous working temperature. Correct material selection must always be based on actual operating conditions.

Classification Temperature vs. Maximum Working Temperature

Classification Temperature refers to the laboratory-rated temperature at which the ceramic fiber material exhibits controlled linear shrinkage after standardized heat treatment. It is used for material grading and comparison, not for continuous operation.

Maximum Continuous Working Temperature indicates the highest temperature at which the ceramic fiber blanket can be used continuously in real industrial environments without excessive shrinkage, loss of insulation performance, or structural degradation.

Selection principle: Always choose ceramic fiber blankets based on the actual working temperature rather than the classification temperature.

Standard (Regular) Ceramic Fiber Blanket Grades in China

In China, ceramic fiber blankets are commonly divided into regular grades and special grades. Regular grades are mainly alumino-silicate based and suitable for most conventional industrial insulation applications.

These grades are typically expressed as:
(Classification Temperature / Maximum Working Temperature)

Special Ceramic Fiber Blanket Grades

For higher-temperature or more demanding applications, special ceramic fiber blankets are used. These materials contain higher alumina content or zirconium additives to enhance thermal stability and reduce shrinkage under extreme heat.

High-Alumina Ceramic Fiber Blanket

(1350 / 1200)
Improved alumina content provides better resistance to crystallization and longer service life in high-temperature environments.

Zr–Al (Zirconia-Alumina) Ceramic Fiber Blanket

(1400 / 1250)
Zirconium oxide enhances thermal stability, making this grade suitable for industrial kilns and high-duty furnace linings.

Zirconium Ceramic Fiber Blanket

(1500 / 1350)
Designed for extremely high-temperature applications requiring maximum insulation reliability.

How to Select the Right Ceramic Fiber Blanket

• Base selection on the actual continuous operating temperature
• Consider thermal cycling and heating frequency
• Allow a reasonable safety margin
• Balance performance requirements with cost efficiency

Conclusion

Although ceramic fiber blankets are classified by laboratory temperature ratings, real-world performance depends on maximum continuous working temperature. Understanding the difference between regular and special grades ensures safe operation, stable insulation performance, and extended service life.