Silica brick is a kind of acid refractory containing at least 93% SiO2. It is mainly made from tridymite, cristobalite and a small amount of residual quartz as well as glass phase. Various grades of silica bricks have been us ed in different industries such as the iron and steel industry, glass and c eramic industry, and metallurgy industry.
The raw material is natural silica sand of which SiO2 content should be mor e than 96%. The higher SiO2 content in silica sand, the higher temperature silica bricks resist.
Silica bricks feature high purity, long service life, good thermal conducti vity, high refractoriness under load, and good creep resistance. In additio n, it has accurate size tolerance, pure color and luster appearance.
One of the outstanding characteristics of silica bricks is that silica bric k does not begin to soften under high loads until its fusion point is appro ached. This behavior contrasts with that of many other refractories, for ex ample alumina silicate materials, which begin to fuse and creep at temperat ures considerably lower than their fusion points.
Another of the outstanding characteristics of silica bricks is their resist ance to corrosion by acid slag and iron oxide, but they are easily attacked by basic slag.
The drawback of silica bricks is bad thermal shock resistance because large volume changes take place at elevated temperatures during conversion from one modification to another. Therefore it is mainly used in the continuous operating furnace.
The silica brick can be widely used in coke oven, hot blast furnace, glass furnace and carbon furnace as well as for hot repairs. In glass industry, i t is mainly employed to build the roof and superstructure, doghouse crown, suspended wall of channel, top crown and inlet sealing. In metallurgy indus try, it is adopted as the steel making open hearth regenerator, slag pocket , soaking pit and nozzle brick. In ceramic kilns, it is used in arch crown and other weight bearing areas, hot blast furnace and acid open hearth. It is also used to build the partition walls in coke oven carbonization and bu rning chamber.
Adopting high quality raw materials and advanced technology, Sunrise Refrac tory offers various grades of silica bricks of high quality and excellent p erformance for different applications.