LC 70 Castable is a 70–75% alumina low cement refractory castable designed for higher-temperature and more demanding furnace applications. It is produced using high-purity alumina aggregates, reactive alumina, and a low CaO cement bonding system.
With increased alumina content and a denser microstructure, LC 70 Castable provides higher hot strength, improved thermal stability, and superior resistance to abrasion and chemical attack compared with LC 60 grades.
This castable forms a strong ceramic bond after firing, ensuring excellent volume stability and long service life in continuous operating environments up to 1600°C.
Technical Specifications
| Item | Unit | LC 70 Castable |
|---|---|---|
| Al₂O₃ Content | % | ≥ 75 |
| SiO₂ Content | % | ≥ 12 |
| CaO Content | % | ≤ 1.8 |
| Bulk Density | g/cm³ | ≥ 2.6 |
| Compressive Strength (110°C × 3h) | MPa | ≥ 45 |
| Compressive Strength (1500°C × 3h) | MPa | ≥ 75 |
| Flexural Strength (110°C × 3h) | MPa | ≥ 6 |
| Flexural Strength (1500°C × 3h) | MPa | ≥ 10 |
| Permanent Linear Change (1500°C × 3h) | % | ±0.5 |
| Maximum Service Temperature | °C | 1600 |
| Water Addition | % | 6.0 – 6.5 |
Key Features
High Al₂O₃ content (≥ 75%)
Low cement and low CaO (≤ 1.8%)
Excellent hot strength and load-bearing capacity
Low permanent linear change after high-temperature firing
Dense structure with enhanced abrasion resistance
Good workability and vibration casting performance
Maximum service temperature up to 1600°C
Typical Applications
LC 70 Castable is suitable for severe service conditions in various high-temperature industries, including:
Steel industry: reheating furnaces, ladle back linings, furnace roofs
Cement industry: kiln hoods, preheaters, calciners
Non-ferrous metallurgy: aluminum and copper melting furnaces
Petrochemical and chemical industry: reformers, reactors, incinerators
High-temperature industrial kilns and thermal processing units
Production Details
Raw materials: High-purity alumina aggregates, reactive alumina, low CaO cement, performance-enhancing additives
Manufacturing process: Precise proportioning, high-intensity mixing, and strict quality inspection
Quality control: Chemical composition analysis, physical strength testing, and high-temperature performance evaluation
Recommended water addition: 6.0–6.5%
Installation method: Vibration casting or pouring
Proper curing, drying, and controlled heating are essential to ensure optimal performance.
Packing and Shipping Details
Standard packing: 25 kg moisture-proof paper bags
Bulk option: Jumbo bags available upon request
Palletizing: Wooden pallets with protective wrapping
Transportation: Sea freight, road transport, or rail
Storage: Keep dry and protected from moisture
Frequently Asked Questions (FAQ)
Q1: What is the maximum service temperature of LC 70 Castable?
LC 70 Castable is designed for continuous service up to 1600°C.
Q2: What is the recommended water addition?
The recommended water addition is 6.0–6.5%, depending on installation conditions.
Q3. How does LC 70 compare with LC 60 Castable?
LC 70 Castable has higher alumina content, better hot strength, and higher temperature resistance, making it suitable for more demanding applications.
Q4: Is LC 70 Castable resistant to abrasion and chemical attack?
Yes. Its dense structure and high alumina content provide excellent resistance to abrasion, slag, and chemical corrosion.
Q5: What curing and drying procedures are required?
After installation, proper curing at ambient temperature is required, followed by controlled drying and heating according to a recommended heating schedule.
