The application of mullite insulation bricks and the operating temperature of different grades

Mullite insulation bricks are generally marked with JM, where J is the pinyin “Juqing” for lightweight and M is the pinyin “Molaishi” for mullite. They are mainly used for insulation in the lining of various high-temperature furnaces to improve the insulation effect and reduce energy consumption; Mullite insulation bricks are also used for insulation in equipment such as thermal power plants and nuclear power plants.

But different grades of mullite insulation bricks are used at different temperatures area. According to national standards, JM-23, JM-26, JM-28, JM-30, and JM-32 are generally classified into different levels, and JM-32 is not widely used. The usage ratio of 26 and 28 is relatively high.

JM-23 mullite insulation brick with Al2O3 content of 48%, operating temperature of 1300 ℃, and bulk density ranging from 0.55-1.5, with the most commonly used being 0.8 and 1.0 and bulk density. The variation of the linear change on reheating is within ± 1 at 1300 ℃ × 24h.

JM26 mullite lightweight brick, Al2O3≥55%, The operating temperature is 1400 ℃, and the bulk density ranges from 0.55-1.5g/cm3. The most commonly used ones are 0.8 and 1.0g/cm3. The linear change on reheating between 0.7-0.8 at 1400 ℃ for 24 hours.

JM28 mullite insulation brick, Al2O3≥65%, The usage temperature is 1500 ℃, and the bulk density ranges from 0.55-1.5. The most commonly used ones are 0.8 and 1.0 and bulk density. The linear change on reheating at 1500 ℃ for 24 hours at 0.7.

The Al2O3 content of JM30 is ≥72%, with a usage temperature of 1600 ℃ and a bulk density ranging from 0.55-1.5. The most commonly used densities are 0.8 and 1.0. The variation of linear change on reheating is 0.6 at 1600 ℃ for 24 hours.

JM32 is not frequently used and is usually customized for production according to the user's special requirements.

Different grades of mullite insulation bricks are used at different operating temperatures, and different furnace types are selected according to the temperature and operating conditions of the user's kiln. But there are also other indicator requirements, which are produced and formulated according to different requirements of the manufacturer.