Light thermal insulation brick refers to the internal structure of porous finalize the design of refractory brick products, small volume density, high porosity, excellent heat insulation high temperature, can also be called light refractory brick or light thermal insulation brick.

Light insulation brick according to the material used in different raw materials, divided into a variety of, such as Clay, Silicon and High Alumina and other raw materials made of called light clay brick, light silicon brick and light high alumina brick. The composition characteristics, service temperature and use of lightweight thermal insulation brick are as follows:

Lightweight clay insulation brick: Refers to the alumina content of 30%-46% light refractory brick, clay clinker or light clinker and plastic clay as the main raw material, using combustible method production. The bulk density is 0.75-1.20g/cm3, the compressive strength is 2.0-5.9MPa, the thermal conductivity is 0.221-0.442W (M.K), and the service temperature is 1200-1400℃. It is used as insulation material for all kinds of industrial kilns without contact with melt and erosive gas.

Lightweight high alumina insulation brick: It refers to the light firebrick with Al2O3 content above 46%.Made of natural high bauxite clinker as the main material called ordinary light high alumina brick; Made of fused or sintered alumina as raw materials called light corundum brick, the main crystal phase is based on corundum. Lightweight high alumina bricks are usually produced by foam method, with a volume density of 0.4-1.35g/cm3, a porosity of 66%-75%, a compressive strength of 1.3-8.1mpa, and a thermal conductivity of 0.291-0.582W (M.K). Ordinary light high aluminum brick service temperature of 1350-1500℃, suitable for hydrogen, CO and other gases as a protective atmosphere of the kiln. The working temperature of light corundum brick reaches 1650-1800℃. It can directly contact the kiln lining of flame, but it is not suitable to be eroded by slag.

Mullite lightweight insulation brick: It is to point to Al2O3 content 50%-85% light firebrick. High quality insulation material with mullite as the main crystalline phase and the combined phase. The main characteristics are: high structural strength at high temperature, low creep at high temperature, small coefficient of thermal expansion, excellent thermal shock resistance. According to the aluminum content and volume density, the temperature is 1350-1700℃, can directly contact the flame of the kiln working layer lining.

Silicon thermal insulation brick: It refers to the heat insulation silicon refractory brick, its SiO2 content in more than 90%, and the volume density is less than 1.2G /cm3. The bulk density is 0.9-1.1g/cm3, the compressive strength is 2.0-5.9MPa, the thermal conductivity is 0.35-0.42W (M.K), and the service temperature is 1200-1500℃. It is suitable for high temperature kiln without contact with molten slag, such as heat insulation material of high temperature hot blast furnace silicon brick lining and heat insulation of glass kiln silicon brick masonry.

Anorthite lightweight insulation brick: It is mainly divided into two kinds, one is made of anorthite as the main raw material, the other is mainly anorthite combined with light mullite brick (need to add ankyanite raw materials). It is characterized by small volume density, small thermal conductivity, good resistance to thermal shock, and strong resistance to reducing atmosphere. The temperature is 1100-1300℃. It is suitable for heat insulation lining of hot blast furnace, soaking furnace and heating furnace in iron and steel industry, and heat insulation lining of catalytic cracking furnace in petroleum industry.

In addition to the above commonly used light thermal insulation brick, there are suitable for alkaline erosion of light refractory brick, such as magnesium thermal insulation brick, chromium thermal insulation brick, zirconia insulation brick, silicon carbide lightweight thermal insulation brick.