Ceramic Fiber Insulation Solution for Glass Tempering Furnaces

1. Overview of Glass Tempering Furnaces

Glass tempering furnaces, also called tempering equipment or tempering units, come in various configurations: batch or continuous, overhead or horizontal, electrically or gas-heated.

The tempering process typically heats glass near its softening point (~650 °C) and then rapidly cools it with air, creating a compressive stress layer on the surface and a tensile stress layer internally. This process improves glass strength and reduces breakage when external forces are applied.
Standard flat glass lengths vary depending on application, commonly around 4 m or 10 m. Furnace chamber temperatures can reach up to 800 °C, usually with electric resistance heating.
2. Insulation Structure of Glass Tempering Heating Furnaces

To prevent contamination of glass during heating, ceramic fiber blankets or modules are generally not used. Current furnace linings typically adopt standard SUNTHERM ceramic fiber boards for the furnace roof, walls, and floor, arranged in layers for a total insulation thickness of 250 mm.

3. Technical Advantages
Temperature differences between the furnace edges and center can cause stress patterns in glass, which cannot be completely eliminated. Well-designed tempering furnaces minimize the visibility of these stress patterns. Ceramic fiber boards are lightweight, easy to install, and have low thermal conductivity, providing excellent thermal insulation. This helps reduce visible stress patterns and improves the yield rate of tempered glass products.