Sillimanite Brick

Sillimanite Brick

Product Parameters

Product Introduction of Sillimanite Refractory Bricks
Manufacturing Materials and Process
Sillimanite refractory bricks mainly use sillimanite concentrate as the raw material, with the chemical composition of Al2O3·SiO2. It can transform into mullite and free silica at high temperatures, endowing the bricks with good high – temperature properties. Binders like calcium aluminate cement or aluminum dihydrogen phosphate, and additives such as fluxes are added. The binders ensure the brick’s structural stability, and the additives adjust the firing temperature and improve sintering performance.
First, crush and screen the sillimanite concentrate to a suitable particle size. Accurately weigh the raw materials and additives according to the formula and mix them evenly in a mixing equipment. Then, use mechanical pressing or isostatic pressing to form green bodies with accurate dimensions and a tight structure. Dry the green bodies in a drying kiln with strict temperature and humidity control to remove moisture and prevent defects during sintering. Finally, sinter the dried green bodies in a high – temperature kiln at 1350℃ – 1500℃, promoting the phase transformation and chemical reactions of sillimanite to form a stable mullite – phase structure and optimize product performance.

Product Features 
High Refractoriness: The refractoriness is 1750℃ – 1810℃. It remains stable at high temperatures, effectively resists softening and melting, and provides fire – resistant protection for high – temperature industrial equipment.
Excellent Thermal Shock Resistance: The phase transformation of sillimanite at high temperatures absorbs thermal stress, enabling it to withstand rapid temperature changes, maintain structural integrity under alternating hot and cold conditions, and reduce cracking and spalling due to thermal shock.
High Load – Bearing Softening Temperature: Generally 1500℃ – 1600℃, it’s not easy to soften and deform under high – temperature and pressure, ensuring the structural stability of high – temperature industrial equipment during operation.
Good Chemical Stability: It resists most acidic and alkaline slags well, maintaining its chemical composition and structure stability in complex chemical – erosion environments, and extending the equipment’s service life.
Good High – Temperature Volume Stability: With little volume change at high temperatures, it ensures the tightness and integrity of the masonry, avoids problems like increased gaps and loose structures due to volume changes, and improves the sealing performance and thermal efficiency of high – temperature industrial equipment.

Main Application Areas 
Steel Industry: Widely used in hot – blast furnaces, soaking pits, reheating furnaces, etc. In hot – blast furnaces, its high refractoriness, thermal shock resistance, and high load – bearing softening temperature can withstand high – temperature hot air and periodic temperature changes, ensure stable operation, increase hot – air temperature and quality, and improve steel production efficiency and quality.
Glass Industry: Commonly used in the regenerators and small furnaces of glass kilns. In regenerators, its good thermal shock resistance and chemical stability enable it to adapt to high – temperature flue – gas scouring and temperature changes during heat – exchange, resist the erosion of acidic components in flue gas, ensure normal operation, and improve the heat – recovery efficiency of glass kilns.
Ceramics Industry: Plays an important role in the kiln linings and shed plates of ceramic kilns. With high – temperature volume stability and chemical stability, it can withstand the high temperatures and chemical atmospheres during ceramic firing, ensure the kiln’s structural stability, and help improve the quality and production efficiency of ceramic products.