Fused cast alumina block is made of pure alumina powder(>95%) and a small amount of additions (soda sand and quartz sand). There are commercially 3 types of fused cast alumina blocks: Beta fused cast alumina block, Alpha-beta Fused cast Alumina Block and Alpha fused cast alumina block.
The manufacturing process of fused cast alumina block includes mixing the raw material, melting it in the electric furnace, casting, annealing, machining and then getting the final products. First melt the raw materials in an electric arc furnace. When the material has become molten and its chemical and physical characteristics have been adjusted to the desired condition, pour the molten material into a mold. Then the cast product is processed with machines into the final product.
Alpha-beta Fused cast Alumina Block is formed by the compact structure of alpha alumina and beta alumina crystals in a most ideal proportion which is approximately 50% and 50% respectively, where intertwined crystals of both materials result in a very dense structure. Below 1350 ℃, it has excellent corrosion resistance against molten glass and great performance against contamination to molten glass, thus it is very suitable for paving blocks and fore-hearth channel blocks. When in contact with molten glass, it barely produces any blistering or stones. So, it may be widely used in working tank, feeder channels, superstructures and lipstone, etc. In soda-lime container furnaces, it is installed in the Alcove and channel areas, as alternative to fused cast AZS for Alcoves and as alternative to fused cast AZS, zirmul, sinter-alumina and other sinter refractories for channels.
Beta fused cast alumina block comprises of a majority of beta alumina crystals and a slight portion of alpha alumina crystals in compact structure. Moreover, the intersected texture of large beta-alumina ensures great dimensional stability and great resistance against spalling. Its property of base saturation enables a higher resistance to alkali vapor, thus it has excellent thermal shock resistance and does not form molten droplets. It is the best material for molter crown, port crown, feeder channel, ect. Its neutrality against soda vapors makes it the best choice for the downstream part of superstructures in demanding applications.
Alpha fused cast alumina block is an ideal product for the lower temperature zones of the glass melting furnaces due to its high density, superior corrosion resistance and low blister potential. It is also an ideal material for Metallurgical Titanium Furnace because the superior thermal stability.
Sunrise provides high quality fused cast alumina block at a competitive price. It can be widely used in glass furnaces and improve the service life of glass furnaces effectively.