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Silica Bricks
Brand: HongTai Refractory
Category: Alumina & Silica Bricks
SiO2: ≥94%
Payment Terms: T/T, Credit Cardse, E-Checking, Alibaba Trade Assurance
Product Information
Introduction
Technical Data
Properties
Applications
Types
Introduction
Silica bricks are refractory bricks made predominantly of silicon dioxide (SiO2). High-quality silica bricks contain over 94% SiO2, giving them exceptional refractoriness and chemical inertness. Silica bricks soften at temperatures over 1600°C and can withstand extreme chemical environments.
Our silica bricks are ideal for lining furnaces, ovens, kilns, and other equipment that processes materials at high temperatures. They improve thermal efficiency, prolong equipment lifetime, and boost productivity in glass, ceramics, metallurgy, and other industries.
Technical Data
| Item | GZ-96 | GZ-95 | GZ-94 |
| SiO2, %, ≥ | 96 | 95 | 94 |
| Fe2O3, %, ≤ | 1.0 | 1.2 | 1.4 |
| Apparent porosity, %, ≤ | 22(24) | ||
| Normal temperature compressive strength, MPa, ≥ | 35(30) | kg/pcs,＜20Kg | |
| 30(25) | kg/pcs, ≥20Kg | ||
| 0.2MPa Load softening temperature, ≥ | 1660 | 1650 | 1640(Colloidal silica1620) |
| True Density, g/cm3, ≤ | 2.34 | 2.35 |
Properties
• High Silica Content (SiO2)
• High Refractoriness
• Excellent Chemical Inertness
• Low Thermal Expansion
• Low Thermal Conductivity
• High Strength
• Abrasion Resistance
• Corrosion Resistance
• Load Bearing Capacity
• Porous Structure
• Permeability
• Insulation
• High Thermal Shock Resistance
Applications
| Industry | Application |
|---|---|
| Glass industry | Glass melting furnaces, regenerative chambers, annealing lehrs |
| Steel industry | Coke ovens, hot blast stoves, steel ladles |
| Non-ferrous metals industry | Copper smelting furnaces, refining furnaces |
| Ceramics industry | Ceramic kilns, tunnel kilns |
| Chemical industry | Acid-resistant structures, chemical processing equipment |
Types
Silica bricks for coke ovens
A coke oven is a crucial, long-term, continuous-use thermal equipment designed to dry distill coal by heating it to 950-1050℃ without air, resulting in coke and other by-products. Silica bricks are the preferred refractory material for coke ovens due to their excellent thermal conductivity, high load softening temperature, good high-temperature mechanical strength, and stable high-temperature volume change. They also have outstanding refractoriness, minimal residual expansion, and strong resistance to acid slag erosion. Silica bricks are used in all major parts of coke ovens, including the heat storage chamber wall, ramp, carbonization chamber bottom, furnace wall, and roof. The use of silica bricks in coke ovens can increase the combustion chamber temperature, shorten the coking time, boost the production capacity of the coke oven, and extend its lifespan. As a result, modern large coke ovens are primarily constructed using silica bricks.| Item | Silica bricks for coke oven | Silica bricks for coke oven |
| Furnace bottom, furnace wall | Other | |
| SiO2, %, ≥ | 94.5 | 94 |
| Al2O3, %, ≤ | 1.2 | 1.5 |
| Fe2O3, %, ≤ | 1.2 | 1.5 |
| CaO, %, ≤ | 3.0 | 3.0 |
| Na2O+K2O, %, ≤ | 0.35 | 0.35 |
| Apparent porosity, %, ≤ | 22 | 24 |
| Normal temperature compressive strength, MPa, ≥ | 35 | 28 |
| 0.2MPa Load softening temperature, ℃, ≥ | 1650 | |
| True Density, g/cm3, ≥ | 2.33 | 2.34 |
| Reburn line change, %, 1450℃x2h | 0-0.2 | |
| Coefficient of thermal expansion 1000℃, %, ≤ | 1.28 | 1.3 |
Silicon bricks for glass kilns
Silica bricks are the most widely used and essential brick type in float glass kilns. In large glass kilns, silica bricks are primarily employed in the melting section and working section of the kiln roof swan, chest wall, front and rear end walls, heat storage room top swan, and heat storage room upper partition wall. Silica bricks used in glass kilns have a SiO2 content ranging from 96-98% and a density of 2.35-2.38g/cm3. They exhibit high structural strength at high temperatures, with a high load softening temperature (1640~1700℃) and low creep rate. After absorbing a small amount of alkali components, they experience very slight fusion corrosion, which does not reduce the structural strength of the kiln roof. Silica bricks for glass kilns possess the following characteristics:- High-temperature volume stability.
- Minimal contamination of the glass liquid.
- Resistance to chemical erosion.
- Low bulk density, which can reduce the weight of the furnace body.
| Item | Unit | KBG-96a | KBG-96b | KBG-95 | |
| SiO2 | ≥ | % | 96 | 96 | 95 |
| FeO3 | ≤ | % | 0.6 | 0.8 | 1.0 |
| Melting index，Al2O3+2R2O3 | ≤ | % | 0.5 | 0.7 | – |
| Apparent porosity | ≤ | % | 21 | 22 | 22 |
| True Density | ≤ | g/cm3 | 2.34 | 2.34 | 2.34 |
| 0.2MPa Load softening temperature | ≥ | ℃ | 1680 | 1670 | 1670 |
| Normal temperature compressive strength | ≥ | MPa | 40 | 35 | 30 |
| re-burn line change. 1450℃*2h | ≤ | % | +0.2 | +0.2 | +0.2 |
Silica bricks for hot blast furnaces
Silica bricks for hot blast furnaces possess the following product characteristics:- They remain stable in volume under long-term high-temperature and high-load conditions, with a low high-temperature creep rate, making them suitable for continuous use in 1 or 2 blast furnaces.
- They exhibit excellent thermal shock resistance above 600 degrees, enabling them to adapt to changes in hot blast furnace temperature and maintain the integrity of the masonry.
- Their chemical resistance is superior to clay bricks and general high alumina bricks.
- The thermal conductivity of silica bricks for hot blast furnaces is higher than that of clay bricks and high alumina bricks, making them ideal for storing and releasing heat quickly.
| Item | Vault and furnace wall tiles | Checker bricks |
| SiO2 % ≥ | 95 | 95 |
| Al2O3 % ≤ | 1.0 | 1.0 |
| Fe2O3 % ≤ | 1.2 | 1.2 |
| Apparent porosity % ≤ | 22 | 24 |
| Normal temperature compressive strength MPa ≥ | 40 | 30 |
| 0.2MPa Load softening temperature℃ ≥ | 1650 | 1650 |
| True Density g/cm3 ≥ | 2.33 | 2.34 |
| 0.2MPCreep rate % 1550℃ 0-50h ≤ | 0.8 | 0.8 |
| Coefficient of thermal expansion 1000℃ % ≤ | 1.26 | 1.26 |
Semi-silica brick
Semi-silica bricks are a type of quartz clay brick, consisting of an aluminous silicate refractory product with an alumina content of 15-30%. They are typically made from refractory clay containing quartz sand, chlorite clay, or tailings from kaolinite beneficiation. Semi-silica bricks have a refractoriness of 1670℃, with a load softening point of no less than 1250℃. Compared to silica bricks, semi-silica bricks exhibit better resistance to rapid cold and heat, as well as superior volume stability. They are primarily used as the refractory layer of steel drum linings and steel pouring systems. Additionally, they can be used for the hot furnace roof, heat storage chamber lattice brick, iron furnace lining, various kiln furnace bottoms, and flues, among other parts.| Name | Semi-silica brick |
| Fire resistance，℃ | 1630-1650 |
| Bulk density，g/cm3 | 2.10 |
| Apparent porosity，% | 18 |
| Normal temperature compressive strength，MPa | 29 |
| Load softening temperature（T6.6），℃ | 1490 |
| Al2O3，% | 21.59 |
| SiO2，% | 76.58 |
| Fe2O3，% | 0.83 |
