High Alumina Castable (85% Al₂O₃)
Main Chemical Compositions & Categories
This castable consists of very high-purity alumina aggregates (typically high-grade Bauxite, Tabular Alumina, or White Fused Alumina) and a binding system. Due to the high Al2O3 target, it is typically formulated as a Low Cement Castable (LCC) or Ultra Low Cement Castable (ULCC) to minimize fluxing impurities.
| COMPONENT | CONTENT | KEY FEATURE | PRIMARY ADVANTAGE |
| Aggregate | Tabular/Fused Alumina | Extremely high purity | Maximum hardness and refractoriness |
| Binder | High-Purity Calcium Aluminate Cement (CAC) | Minimal CaO content | Superior hot strength and creep resistance |
| VARIANT | CaO Content (from CAC) | HOT STRENGTH PERFORMANCE |
| LOW CEMENT (LCC) | 1% to 2.5% | Superior structural integrity and minimized liquid formation. |
| ULTRA LOW CEMENT (ULCC) | < 1.0% | Near-zero creep for maximum performance under load. |
Key Properties and Performance
| PROPERTY | TYPICAL PERFORMANCE | MECHANISM OF ADVANTAGE |
| Hot Strength/Creep | OUTSTANDING | High Al2O3 purity and low CaO minimize detrimental glassy phases, resulting in minimal deformation (CISC). |
| Abrasion Resistance | EXTREME | The high concentration of hard alumina aggregates (e.g., Tabular Al2O3) provides superior resistance to wear. |
| Refractoriness (RUL) | EXTREME | Approaches the limits of oxide castables, allowing stable service up to 1800°C. |
| Slag Resistance | VERY GOOD | Highly resistant to acidic and neutral slags, as well as molten aluminum penetration. |
Advantages and Key Characteristics
The 85% Al2O3 castable is a high-end workhorse chosen when severe abrasion, high structural load, and continuous high-temperature service require performance that significantly exceeds 70% Al2O3 grades.
- Maximum Abrasion and Erosion Resistance: This is the most common reason for selecting this grade. The high volume of densely packed, extremely hard alumina particles (often Tabular Al2O3 resists mechanical scouring from high-velocity burdens, flue gases, or molten metal flow.
- Exceptional Structural Stability: By limiting the amount of low-melting CaO and SiO2 (fluxes), particularly in LCC/ULCC formulations, the brick maintains its rigidity and dimensional stability under structural load at peak operating temperatures, ensuring reliable support.
- Corrosion Resistance: High purity makes it an excellent choice for contact with molten aluminum (non-wetting) and various aggressive chemical vapors and neutral/acidic slags.
- Longevity and Reduced Downtime: The superior physical properties lead to significantly extended refractory campaigns, offsetting the higher initial material cost through reduced maintenance and plant downtime.
Typical Industries and Applications
This castable is used in the most severe environments of medium-to-large industrial furnaces:
- Ferrous Industry (Steel): Tap-hole blocks, ladle impact zones, EAF delta sections, high-wear zones in reheating furnace hearths, and coke oven charging hole walls.
- Non-Ferrous Industry: High-wear launders, metal contact zones in holding furnaces (especially aluminum), and electrolytic cells.
- Cement & Chemical Industry: High-abrasion zones like cyclone outlets, transfer pipes, and linings in high-heat fluid catalytic crackers (FCC units).
Furnace Areas and Service Zones
They are specified for structural and wear-critical areas in the hottest zones:
- IMPACT AND WEAR ZONES: Where the product or molten metal stream directly impacts the lining.
- CRITICAL LOAD-BEARING AREAS: Used where structural failure from creep would be catastrophic.
- SLAG LINE (ACIDIC/NEUTRAL): Used to resist severe chemical and physical attack.
Key Data Sheet Properties to Consider
Selection criteria focus on the bond type and wear resistance:
- Al2O3 Content: Must be 85%$ (±2%) to meet the specification.
- CaO Content: CRITICAL VALUE. Must be checked. An LCC or ULCC formulation is highly recommended to maximize hot strength and creep resistance.
- Abrasion Resistance Index: Look for supplier data demonstrating high resistance to wear (often using the ASTM C704 test).
- Firing Temperature (MST): Should be rated up to 1750°C to 1800°C for maximum performance.
Technical Guidance: Similar to all high-density castables, the Al2O3 castable requires a strictly controlled, multi-stage dry-out and heat-up schedule to safely remove the significant amount of water of hydration and mixing. Insufficient drying is the most common cause of premature failure in these high-performance materials.
✨ Customization Services
We offer product customization services, allowing you to tailor the appearance, dimensions, or specific markings of items like refractory shapes or bricks. This includes options for incorporating specific geometric requirements to ensure seamless integration into your process systems.
🔬 Sampling for Testing & Validation
Free product samples are available for thorough testing and validation. This allows you to confirm the quality, compatibility, and performance of our materials—such as specific bricks, castables, or raw materials—before committing to a full order.
💡 Expertise in Refractory Solutions
Leverage our deep expertise to receive detailed, application-specific refractory solutions. We move beyond just selling products by providing comprehensive plans that encompass material selection, installation guidance, and performance optimization to maximize the lifespan and efficiency of your high-temperature processes.
Rabatec products are exclusively manufactured in facilities that have achieved rigorous ISO certifications across Quality (ISO 9001), Environmental Management, and Occupational Health & Safety. This commitment ensures every product, from refractory bricks to specialized equipment, meets the highest global benchmarks for performance, sustainability, and workplace safety.
📦 Logistics Excellence: Shipping, Packaging, and Marking
Minimizing Risk: We manage all logistics to minimize handling touchpoints and transit shock. Our carriers are pre-vetted for their experience in transporting heavy, fragile, and sensitive industrial materials.
Traceability: Every shipment includes comprehensive documentation and tracking information, providing end-to-end visibility and ensuring precise delivery coordination for your site.
Protection is Paramount: Our packaging strictly follows industry standards to prevent damage, corner chipping, and moisture absorption—especially critical for materials like Basic Refractory Bricks and Refractory Mortars & Mixes.
Robust Palletization: Products are secured on fumigated, high-strength export pallets (e.g., 1100x950mm or similar sturdy dimensions) using heavy-duty strapping and durable protective wrapping (polyethylene sheeting, cardboard, etc.) to withstand long-distance travel and multiple loadings.
Moisture Control: Sensitive materials are protected with appropriate sealing and, where necessary, desiccants or moisture-vapor proof enclosures to maintain the product's integrity until installation.
Clear Identification: All outer packaging is clearly marked on multiple sides with large, legible text for immediate identification and safe handling.
Full Traceability: Markings include all essential data points: Product Name, Quality Grade, Batch Number, Quantity, Net/Gross Weight, Order Number, and the Final Destination/Construction Area. This ensures every pallet can be accounted for and correctly staged upon arrival.
Safety & Compliance: We adhere to all regulatory requirements for marking, labeling, and placarding—especially for any items classified as Dangerous Goods—to ensure full compliance with international and domestic transport regulations.
❓ Frequently Asked Questions (FAQ)
Question | Elaborated Answer |
Q: What is the Refractoriness Under Load (RUL) of your refractories? | A: Refractoriness Under Load (RUL) is a critical property that defines the maximum temperature our materials can withstand while under compressive stress before deforming (softening). Since we offer a wide range of materials—from Alumina-Silicate Bricks to high-performance Silicon Carbide Bricks—the RUL varies significantly. For specific product data, please refer to the product data sheet or submit a quote request for the material you are interested in. |
Q: Where are the Rabatec refractories and materials produced? | A: Our products are primarily sourced from specialized manufacturing plants in China. Crucially, these facilities have all undergone rigorous audits and achieved comprehensive ISO certifications (Quality, Environment, and Safety), ensuring that production adheres to the highest global standards for consistency and performance. |
Q: What refractory materials does the company offer? | A: We supply a comprehensive portfolio of advanced refractory solutions, including: Shaped Products: Alumina & Silica Bricks, Basic & Specialized Bricks (e.g., Magnesia), SiC & Structural Ceramics, and Precast Shapes. Monolithic Products: Refractory Castables, Mixes & Mortars. Insulation: Insulation Fibre and High-Performance Insulation Products. |
Q: How should I choose the appropriate refractory material for my application? | A: Selecting the correct refractory is paramount to process efficiency. The choice depends on three key factors: 1. Operating Environment: Maximum process temperature and thermal cycling (shock). 2. Chemical Attack: Type of slag, molten metal, or corrosive gas being handled (acidic, neutral, or basic). 3. Mechanical Stress: Abrasion, erosion, and static load requirements. We recommend utilizing our detailed refractory solutions service to consult with our engineers for an optimized, application-specific recommendation. |
Q: Which monolithic material should I choose when patching an existing lining? | A: For patching and minor repairs, the ideal monolithic material depends on the parent lining material, the patching depth, and the need for a rapid return to service. Common choices include: Refractory Mortars & Mixes (for minor joints/surfaces) or Plastic Refractories (for areas requiring physical compaction). Always choose a patch material chemically compatible with the existing lining to ensure proper bonding and service life. |
Q: Can I receive product samples before placing a major order? | A: Yes. We gladly provide product samples for your internal testing and validation purposes. This ensures you can confirm the quality, composition, and fit of the material—such as our Refractory Castables or Alumina-Silicate Bricks—in your specific operational environment before committing to a bulk purchase. |
Q: Do you provide certifications to verify material quality? | A: Absolutely. We provide product-related inspection certificates and quality assurance documentation upon request. This verifies that your order has passed all internal quality control checks and meets the required material specifications and industry standards. |
Q: What measures are taken for product protection during transport? | A: We ensure quick, reliable transport by using robust, industrial packaging that strictly follows industry standards. This includes high-strength palletization, heavy-duty strapping, and weather-resistant wrapping to protect fragile items like bricks and mixes from corner chipping, mechanical damage, and moisture during transit. |
