What Are The Refractories Commonly Used in Glass Melting Kilns
Refractory is the main component of glass melting kiln, which has a decisive impact on glass quality, energy consumption and product cost. The future of glass melting technology depends to a certain extent on the progress of refractory manufacturing technology and the improvement of product quality.
Refractories commonly used in glass melting kilns are mainly divided into four categories: fused cast refractories, sintered refractories, amorphous refractories and thermal insulation refractories. Each class of material contains several types. The chemical composition, physical properties, size error and appearance types of refractories should meet national standards or industry standards, and the latest revised version should be selected, otherwise it should not be delivered.
Silicon bricks are used more in glass melting kilns, and the main component is silicon dioxide (SiO2). The silica brick used in glass melting kiln requires SiO2 content of more than 94%, the maximum use temperature is about 1600~1650℃, and the density is 1.8~1.95g/cm3. The apparent porosity should be less than 22%, and the larger the porosity, the worse the quality of silicon brick. Most of the appearance of the silicon brick is white crystal, the microscopic composition of crystalline quartz crystals, because the silicon brick at high temperature to occur crystallization transformation, volume expansion, especially in 180 ~ 270 ° C and 573 ° C or so, crystallization transformation is more intense, so in the kiln and cold repair process to adapt to the silicon brick crystallization transformation and take appropriate measures such as tension strip.
The main composition of clay brick for glass kiln is Al2O3 and SiO2, the Al2O3 content is between 30% and 45%, the SiO3 is between 51% and 66%, the density is 1.7~2.4g/cm3, the apparent porosity is 12%~21%, and the maximum use temperature is 1350~1500℃. In the glass industry, clay bricks are used to lay the bottom of kilns. Pool walls of the work section and access road, walls of the regenerator, arch, lower checker and flue. Clay bricks expand in volume as they rise in temperature. When the temperature exceeds 1450℃, the volume will shrink again.
The main component of mullite brick is Al2O3, and its content is about 75%, because it is mainly mullite crystal, so it is called mullite brick. The density is 2.7-32g /cm3, the porosity of the opening is 1%-12%, and the maximum operating temperature is 1500~1700℃. Sintered mullite is mainly used for laying regenerator walls.
JIYGO REFRACTORY & ABRASIVE LIMITED
