Lightweight thermal insulation castables are composed of refractory lightweight aggregate and powder, as well as binders, additives, etc. In addition to excellent thermal insulation properties, lightweight thermal insulation castables also have good strength, wear resistance, and thermal shock resistance, and it has good workability, strong impermeability, and does not require acidification treatment. The lightweight thermal insulation castable is easy to ensure the compactness and fullness of the mortar joints of the masonry, and can significantly improve the air tightness, integrity, and corrosion resistance of the inner lining of the chimney. It can be used to line various equipment such as furnace walls, kiln roofs, and pipes to provide insulation and prevent heat transfer.
| Item/Grade | QJ-0.5 | QJ-0.8 | QJ-1.0 | QJ-1.1 | QJ-1.3 | QJ-1.5 | QJ-1.8 | |
|---|---|---|---|---|---|---|---|---|
| Bulk Density (g/cm³) | 0.5 | 0.8 | 1.0 | 1.1 | 1.3 | 1.5 | 1.8 | |
| Max. Service Temperature/℃ | 1150 | 1200 | 1250 | 1250 | 1300 | 1300 | 1350 | |
| Thermal Conductivity Coefficient ≤/[W/(m·K)] | 350℃ | 0.15 | 0.25 | 0.3 | 0.4 | 0.45 | 0.6 | 0.65 |
| 700℃ | 0.20 | 0.30 | 0.4 | 0.45 | 0.5 | 0.7 | 0.75 | |
| Cold Crushing Strength ≥/MPa | 110℃*24h | 1.5 | 2.0 | 4.0 | 5.5 | 10 | 15 | 20 |
| 1000℃*3h | 1.5 | 2.0 | 5.5 | 6.5 | 15 | 20 | 30 | |
| Permanent Linear Change (1000℃*3h)/% | -1.5 | -1.0 | -1.0 | -0.5 | -0.5 | -0.5 | -0.5 | |
Lightweight thermal insulation castables use lightweight aggregate as the main component. It has a high pore structure and contains a large number of pores, which effectively reduces the heat conduction path and effectively reduces thermal conductivity.
Compared with traditional dense castables, lightweight castables have a lower density, and the lower density results in lighter-weight materials, so it is easier to handle, transport, and install, reducing structural loads.
Since the material of lightweight thermal insulation castables contains pores, it can act as a buffer and can absorb and dissipate thermal stress generated during rapid temperature changes. Additionally, low thermal conductivity reduces thermal gradients and minimizes the potential for shock.
Lightweight castables usually contain acid-resistant aggregates, such as high alumina, silica, etc. These materials are not prone to chemical reactions with acidic substances, thereby enhancing corrosion resistance.
Lightweight insulation castables are used in various power generation facilities, such as boilers, furnaces, and flue gas ducts. They provide insulation and help in reducing heat loss, improving energy efficiency, and enhancing overall thermal performance.
In the petrochemical industry, lightweight insulation castables can be used in equipment like reformers, crackers, and heaters. They help in maintaining high temperatures, reducing heat transfer, and improving the overall efficiency of the processes.
Lightweight insulation castables are utilized in various metallurgical processes, including ladles, and reheating furnaces. They provide insulation to minimize heat loss, improve temperature uniformity, and optimize the production process.
Lightweight insulation castables are widely used for insulation in high-temperature kilns, such as rotary kilns and tunnel kilns. They help in conserving heat, reducing fuel consumption, and maintaining stable and controlled temperature profiles.