Lightweight thermal insulation bricks, also known as thermal insulation bricks, are commonly used refractory bricks in refractory materials, and lightweight thermal insulation bricks have the characteristics of good thermal insulation performance. Lightweight insulation bricks are generally divided into the following types:
1. Lightweight silica bricks
Lightweight silica brick is a new type of refractory material, often used in the iron and steel industry, generally used in the hot blast furnace wall, high hot air channel, and blast furnace extraction machine is more similar due to the different shapes and parts of the hot blast furnace, the temperature range is usually between 1000 °C ~ 1300 °C, and the load softening temperature is about 1640 °C. In reality, many cases can prove that lightweight silica bricks can be used in kilns below 1500 °C ~ 1600 °C, and can be used for a long time, and can also be used to directly build the surface in contact with hot gas, and can also be used on the roof of a large span.
Second, diatomaceous earth insulation bricks
Diatomaceous earth insulation brick is a lightweight thermal insulation material made of diatomaceous earth, which has good thermal insulation performance and can be built on the back of clay brick as an insulation layer. Diatomaceous earth insulation brick has stable performance and energy-saving effect, and its thermal conductivity and expansion coefficient are small, which can ensure the stability of high-temperature equipment. At the same time, the thermal efficiency of diatomaceous earth insulation bricks has strong anti-permeability performance, is not easy to be bonded by molten matter, and can even resist local mechanical vibration of the kiln without cracking.
3. Polyhydrogen insulation bricks
The product has good thermal insulation performance, because the raw materials are added to expand the material during production, so there are more holes, low thermal conductivity, and good thermal insulation performance.
Because it is made because the expansion can make the brick body irregular, and the further operation and construction to achieve the size that people want, so the cost is higher, although the polyhydrogen brick has superior performance, it also has its own obvious shortcomings, that is, the environmental performance is poor, usually used in large glass furnaces and other aspects.
Fourth, lightweight clay insulation bricks
The aluminum content of lightweight clay insulation bricks is generally between 30% and 46%, which belongs to the porous lightweight insulation materials, built on the back of clay bricks or high-alumina bricks, which can be used as a thermal insulation layer, and some can be coated with a layer of refractory coating on the surface in direct contact with the flame, and the refractory temperature is usually 800-900 °C, and the maximum is not more than 1200 °C. It has the characteristics of high strength, good rigidity and good thermal insulation performance.
5. Lightweight high-alumina insulation bricks
The aluminum content is not less than 48%, it is a good thermal insulation material, which can be used to build the back of high-alumina refractory bricks or lightweight silica bricks, when in direct contact with the flame, the temperature can reach 1350 °C, with light bulk density, small shrinkage value, impermeability, good thermal shock resistance, and refractory up to 700 °C.