Zhengzhou Tyreen Refractory Co.,Ltd
Floating bead lightweight insulation brick is a thermal insulation refractory made primarily from floating beads (cenospheres) extracted from fly ash of thermal power plants. These hollow aluminum silicate glass microspheres are light, thin-walled, and have a smooth surface. Combined with fine refractory clay and binders, they produce bricks with high porosity, low bulk density, and reliable insulation performance.
The bricks are typically formed by the semi-dry method, which keeps the process straightforward and eliminates the need for additional shaping after firing. Standard size is T3 (230 × 114 × 65 mm); other dimensions can be supplied according to project requirements.
Key Features and Advantages
- Main raw material: fly-ash floating beads + refractory clay
- Bulk density range: 0.6–1.2 g/cm³
- Thermal conductivity: 0.25–0.50 W/(m·K) at 350 °C
- Maximum service temperature: up to 1200 °C
- High porosity and low bulk density for effective heat insulation
- Higher cold crushing strength than many traditional lightweight bricks of similar density
- Good thermal shock resistance and small permanent linear change on reheating
- Lightweight construction that reduces load on furnace foundations and steel structures
- Easy installation and potential energy savings of 15–40 % in industrial furnaces
Compared with conventional clay insulation bricks, floating bead bricks generally offer lower thermal conductivity and better strength-to-weight ratio. Relative to calcium silicate boards, they provide superior high-temperature stability and can be used directly as backup lining or filling material behind dense refractory bricks.
Physical and Chemical Properties
Different density grades are available so that the balance between insulation performance and mechanical strength can be matched to the application:
| Items | Performance indicators | |||
| TY-0.6 | TY-0.8 | TY-1.0 | TY-1.2 | |
| Bulk density, g/cm3 | 0.6 | 0.8 | 1.0 | 1.2 |
| Cold crushing strength/Mpa | 2.0 | 3.0 | 3.5 | 4.5 |
| Working temperature, ℃ | 1150 | 1150 | 1200 | 1200 |
| Thermal conductivity, W/m.k(350±25℃） | 0.25 | 0.35 | 0.40 | 0.50 |
These grades allow selection according to the required balance between weight reduction and mechanical strength.
Characteristics
Floating bead lightweight insulation bricks have the advantages of high porosity, low bulk density, and good insulation performance.
It is widely used as an insulation and filling material for the space between refractory bricks and ketone bodies in various industrial kilns to reduce heat loss and achieve high energy utilization efficiency.
Floating bead lightweight insulation bricks are used in industrial kilns and high-temperature machinery equipment in industries such as metallurgy, mechanical equipment, chemical plants, crude oil, decorative building materials, light industry, and power engineering. They can generally be environmentally friendly and energy-saving by 15% to 40%, making them a good new type of lightweight insulation material.
Applications
Floating bead lightweight insulation bricks are widely used as backup insulation or filling material behind dense refractory linings in industrial furnaces. Typical applications include:
- Blast furnaces and hot blast stoves
- Coke ovens and carbon calciners
- Steel ladles and tundishes
- Cement rotary kilns and glass melting furnaces
- Boilers and other high-temperature process equipment
By lowering heat loss through the furnace shell, they commonly contribute to energy savings in the range of 15–40%, while also reducing the structural load on foundations and steelwork.
The combination of low density, stable high-temperature performance, and straightforward installation makes these bricks a practical choice for both new construction and furnace upgrades where thermal efficiency and weight reduction are priorities.
