LC 90 Castable is a 90–92% alumina ultra-low cement refractory castable designed for extreme high-temperature and severe service conditions. It is formulated with high-purity alumina aggregates, reactive alumina micro-powder, and an ultra-low CaO bonding system.
This advanced formulation delivers exceptional hot strength, excellent thermal stability, and outstanding resistance to slag, abrasion, and chemical corrosion, making it suitable for critical furnace linings operating up to 1700°C.
After firing, LC 90 Castable forms a dense ceramic bond with minimal permanent linear change, ensuring long service life and reliable performance under continuous high-temperature operation.
Technical Specifications
| Item | Unit | LC 90 Castable |
|---|---|---|
| Al₂O₃ Content | % | ≥ 92 |
| SiO₂ Content | % | ≤ 5 |
| CaO Content | % | ≤ 1.8 |
| Bulk Density | g/cm³ | ≥ 3.0 |
| Compressive Strength (110°C × 3h) | MPa | ≥ 60 |
| Compressive Strength (1500°C × 3h) | MPa | ≥ 85 |
| Flexural Strength (110°C × 3h) | MPa | ≥ 8 |
| Flexural Strength (1500°C × 3h) | MPa | ≥ 10 |
| Permanent Linear Change (1500°C × 3h) | % | ±0.5 |
| Maximum Service Temperature | °C | 1700 |
| Water Addition | % | 4.0 – 5.0 |
Key Features
Ultra-high Al₂O₃ content (≥ 92%)
Ultra-low cement and low CaO (≤ 1.8%)
Excellent hot strength and load-bearing capacity
Superior resistance to slag, abrasion, and chemical attack
Low permanent linear change and high volume stability
Dense microstructure with low porosity
Maximum service temperature up to 1700°C
Typical Applications
LC 90 Castable is recommended for the most demanding high-temperature environments, including:
Steel industry: ladle working lining, tundish, furnace hot spots
Cement industry: kiln burning zone, kiln hood
Non-ferrous metallurgy: high-temperature melting and refining furnaces
Petrochemical industry: reformers, reactors, gasifiers
Advanced industrial kilns and thermal processing equipment
Production Details
Raw materials: High-purity alumina aggregates, reactive alumina, ultra-low CaO cement, and performance additives
Manufacturing process: Precision batching, intensive mixing, and strict quality control
Quality control: Chemical composition analysis, mechanical strength testing, and high-temperature performance verification
Recommended water addition: 4.0 – 5.0%
Installation method: Vibration casting (recommended) or pouring
Packing and Shipping Details
Standard packing: 25 kg moisture-proof paper bags
Bulk option: Jumbo bags available upon request
Palletizing: Wooden pallets with protective shrink wrapping
Transportation: Sea freight, truck, or rail
Storage: Keep dry and protected from moisture
Frequently Asked Questions (FAQ)
Q1: What is LC 90 Castable?
LC 90 Castable is a high alumina ultra-low cement refractory castable with Al₂O₃ content of around 90–92%. It is designed for extreme high-temperature applications requiring excellent hot strength, abrasion resistance, and thermal stability.
Q2: What is the maximum service temperature of LC 90 Castables?
LC 90 Castables are suitable for continuous service temperatures up to 1700°C, depending on operating conditions and furnace atmosphere.
Q3. What are the main advantages of LC 90 Castables compared with lower alumina grades?
Compared with LC 60 or LC 70, LC 90 Castables offer higher hot strength, lower porosity, better resistance to slag and chemical attack, and longer service life in severe operating conditions.
Q4: How much water is required for mixing LC 90 Castables?
The recommended water addition is 4.0–5.0%, which helps achieve high density and low porosity after installation.
Q5: What curing and drying procedures are required?
After installation, LC 90 Castables should be properly cured at ambient temperature, followed by controlled drying and gradual heating according to a recommended heating schedule to avoid cracking.
