Application of Ceramic Fiber Blanket Inside Furnaces

The application of ceramic fiber blanket inside furnaces is not simply about placing an insulation layer. It is a systematic furnace lining design and installation process. Improper installation may lead to lining detachment, excessive heat loss, and reduced service life.

1. Core Application Methods in Furnaces

1.1 Layered Lining (Most Common & Cost-Effective)

Suitable for: Medium and low-temperature furnaces (≤1000°C)

Method:

· Ceramic fiber blankets are installed layer by layer on the inner furnace wall

· Each layer is staggered (like brickwork) 

· Fixed using anchors and retaining washers 

Key Points:

· Total thickness typically≥50 mm (multi-layer design)

· Joints must be staggered to avoid thermal bridges

· Inner layers can be slightly compressed for better strength

Advantages: Low cost, simple installation
Disadvantages: Shrinkage may occur under long-term high temperature, shorter lifespan compared to modules

1.2 Modular installation (preferred for high-temperature furnaces) 

Applicable to: high-temperature furnaces (≥1000℃, such as 1260℃/1400℃) 

Method: 

• The ceramic fiber blankets are prefabricated into folded modules.

• The modules are directly fixed to the furnace shell through anchor fasteners.

• The modules are installed by being tightly squeezed together. 

Key points: 

• The modules need to be pre-compressed (20%–30%).

• The installation direction must be consistent (to prevent cracking).

• The temperature resistance of the anchor fasteners must be compatible. 

Advantages: 

• Better heat preservation effect

• Longer service life

• Stronger resistance to shrinkage 

Disadvantage: Higher cost than laminated ones.

1.3 Auxiliary Applications

· Furnace Door Sealing:
Ceramic fiber blankets act as flexible sealing materials to prevent heat leakage

· Furnace Roof Insulation:
Used in suspended or modular structures to reduce weight

· Flue & Duct Insulation:
Used for external wrapping or internal lining to reduce heat loss

2. Standard Installation Procedure

https://www.mindelunmaterials.com/product/ceramic-fiber-products.html 

Step 1: Furnace Shell Preparation

· Clean the inner surface (no oil, dust, or rust)

· Mark anchor positions

Step 2: Anchor Installation (Critical Step)

· Weld or bolt anchors to the furnace shell

· Typical spacing: 250–300 mm 

· Use heat-resistant materials (e.g., 310S stainless steel)

Step 3: Blanket or Module Installation

· Layered lining: install blankets layer by layer and compress

· Module lining: install modules sequentially with tight compression

Step 4: Fixing

· Use washers or clips to secure materials

· Prevent sagging or detachment

Step 5: Inspection and Repair

· Check for gaps

· Fill voids with ceramic fiber bulk

3. Key Precautions

Avoid Thermal Bridges

Exposed anchors may conduct heat
→Solution: Cover anchors or use folded module structures

Allow for Shrinkage

Ceramic fiber shrinks at high temperatures
→Modules must be pre-compressed

Prevent High-Speed Airflow Erosion

High-velocity airflow may damage the surface
→Apply coatings or protective shields if necessary

Select Proper Material Grade

· Below 1000°C: Standard grade

· 1000-1260°C: High purity grade

· Above 1260°C: Zirconium-containing grade

4. Summary

· For cost-effective and lower temperature applications→Layered lining 

· For high temperature and long service life→ Module lining system

  For sealing and edges→ Use ceramic fiber blanket as auxiliary material