How To Identify Mullite Insulating Brick

Mullite insulating brick is a type of high alumina reractory with mullite as the main crystalline phase. Generally it contains 65%-75% Al2O3. In addition to mullite, when the Al2O3 content is low, there will be also a small amount of glass phase and cristobalite; when the Al2O3 content is high, there will also be some corundum. 

There are two types of mullite insulating bricks: sinteredbrick and fused brick. It has a high refractoriness and good thermal shock resistance. Its high temeperature properties are up to the Al2O3 content and the distribution of mullite and glass phase. It is mainly used in the hot stove roof, blast furnace stack and hearth, the regenerator of glass furnaces, ceramic sintering furnace and petroleum cracking system dead lining. 

 

Mullite brick is made with synthetic mullite as raw material. Prior to production, pure raw materials are selected. Formulate the materials according to the theoretical composition of mullite. then the materials are finely ground, pressed into billets and sintered at high temperature.

 

When there is no testing equipment, customers can identify the quality of mullite insulating brick by the sound. Knock the brick with a rock, another brick or other hard things. High quality bricks will have crisp sound like the sound of metal crashing, while low quality products have boring sound.