Portland Cement – High-Temp Grade
Portland Cement (OPC) is a hydraulic binder composed primarily of calcium silicates (C₃S and C₂S) and calcium aluminates (C₃A). When mixed with water, it sets and hardens to form a durable concrete.
The term High-Temp Grade is often used in a limited context to describe OPC that meets strict impurity standards (low alkali, low iron) for use in moderate-temperature applications (typically below 1200°C) or as a matrix component for applications like low-duty chimney linings, stacks, or back-up concrete where its high cost-effectiveness is the main driver. It is never used in high-heat zones like the steel slag line or primary furnace linings due to its low melting point.
Main Function and Characteristics
Used as a low-cost, room-temperature hydraulic binder in non-critical, moderate-temperature areas, or in its purest form, as a component for very specific cementitious high-temperature materials.
| CHARACTERISTIC | VALUE RANGE | PRIMARY FUNCTION |
|---|---|---|
| PCE (Refractoriness) | ~1200°C (Softens) | Limited service temperature due to low Al₂O₃/CaO ratio. |
| Primary Phases | C₃S, C₂S (Calcium Silicates) | Forms the bulk hydraulic bond. |
| Cost | LOW | Highly economical compared to CAC binders. |
CLASSIFICATION
- Binding Focus: Hydraulic Non-Refractory Binder – Calcium-Silicate Hydrates (C-S-H)
- Primary Application Focus: Low-Duty Stacks, Back-up Concrete, and Foundry Molds (non-heat exposure)
Key Performance Metrics
| PROPERTY | TYPICAL PERFORMANCE | MECHANISM OF ADVANTAGE |
|---|---|---|
| Compressive Strength | HIGH | Excellent mechanical strength at room temperature. |
| Water Resistance | EXCELLENT | Forms a strong, stable bond when cured in water. |
| Thermal Limit | POOR | Softens and loses strength rapidly above 1200°C. |
- Why OPC is not a Refractory Cement
The high calcium silicate and high total fluxing agent content (alkalis, iron) in OPC are detrimental to high-temperature stability:
- Eutectic Formation: The combination of CaO and SiO₂ forms low-melting-point eutectic liquids (glass) at temperatures as low as 1200°C. When this liquid forms, the cement matrix softens, causing the refractory lining to lose all mechanical strength and collapse.
- Volume Instability: Above 1200°C, the residual Ca(OH)₂ and other phases decompose, causing significant volume changes and porosity, which destroys the integrity of the material.
For nearly all applications above 1200°C, Calcium Aluminate Cement (CAC) is the required hydraulic binder, as its CaO/Al₂O₃ chemistry is much more heat-resistant.
- Specialized High-Temp Use
In rare, specialized instances, OPC (or highly modified cement) can be used as a source of CaO and SiO₂ in a mix designed for very specific chemical reactions with an ultra-high-alumina aggregate to form high-temperature compounds in situ. However, this is niche chemical engineering, not a general-purpose refractory application.
Practical Use: The most common “high-temp” use is as a simple, durable binder for the back-up lining of a furnace—the layer placed between the shell and the hot-face refractory. Since the back-up layer should rarely exceed 500°C to 800°C, OPC may survive, though CAC or refractory insulation materials are generally safer.
✨ 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. |
