Electric Furnace Gunning Mix (Basic)
Main Chemical Compositions & Categories
This mix is composed predominantly of basic oxides, mainly Magnesia (MgO) or Magnesia-Chromia, to ensure chemical compatibility with the furnace’s permanent lining and the MgO-saturated slag. The binding system is often a complex chemical bond (e.g., phosphates, silicates, or hydrated compounds) designed to achieve strong adhesion and a fast, low-temperature set.
| COMPONENT | CONTENT | CHEMICAL BASE | PRIMARY ADVANTAGE |
| Aggregate | MgO or MgO / CaO | Periclase / Dolomite | Basicity, high melting point, slag resistance |
| Binder | Chemical Bond | Phosphate / Sulfate | Fast, reliable setting and adherence to hot lining |
Key Properties and Performance
| PROPERTY | TYPICAL PERFORMANCE | MECHANISM OF ADVANTAGE |
| Basicity | HIGH | Chemically stable against basic EAF slag, minimizing fluxing and corrosion. |
| Adhesion | EXCELLENT | Chemical bonds react rapidly with the hot, prepared lining surface to ensure a durable patch. |
| Application Method | Gunning (Dry or Wet) | High rebound resistance and minimal dust during fast, large-volume, remote application. |
| Density (Post-Firing) | HIGH | High bulk density and low porosity provide good resistance to slag penetration. |
Advantages and Key Characteristics
Basic $\text{EAF}$ Gunning Mixes are essential tools for maximizing the uptime and campaign life of steelmaking furnaces by allowing rapid, in-situ, hot repairs between heats.
- Speed of Repair: Gunning allows for repairs in minutes while the furnace is still hot, minimizing the tap-to-tap time, which is critical for the economic operation of an EAF.
- Chemical Compatibility: The MgO base ensures the repair material is chemically compatible with the basic permanent lining and the MgO-saturated slag, which is used to protect the lining. This prevents localized fluxing and preferential wear.
- Cost-Effectiveness: Gunning is the most cost-effective method for patching large, eroded areas, reducing the need for expensive brick replacement or the use of more costly sintered refractories.
- Dense, Durable Patch: The mixture is formulated to pack densely upon impact, resulting in a low-porosity repair layer that resists slag infiltration and provides a durable, high-refractoriness working face.
- Remote Application: The material is applied using a gunning machine from a safe, remote location (often from outside the open furnace door), protecting the maintenance crew from the intense heat.
Typical Industries and Applications
This mix is specialized for basic steelmaking operations:
- Ferrous Industry (Steel): Specifically, the lining maintenance of Electric Arc Furnaces (EAF), Ladle Furnaces (LF), and sometimes AOD converters.
Furnace Areas and Service Zones
They are specified for high-wear areas in the hot zone:
- EAF SLAG LINE: The most frequent repair area, where chemical and thermal attack are concentrated.
- EAF HOT SPOTS: Wear zones opposite the burners or highly exposed to the electrode arc.
- LADLE FREEBOARD/SLAG LINE: Used for patching the MgO or Dolomite lining of steel ladles above the metal line.
Key Data Sheet Properties to Consider
Selection criteria focus on refractoriness, bonding, and application characteristics:
- MgO Content and Purity: CRITICAL VALUE. Must be high (> 85%) and compatible with the existing lining.
- Rebound Loss: The percentage of material that bounces off the wall during gunning (lower is better, typically < 15%$ to 20%).
- Bonding Type: Verify if the mix is designed for hot (chemical bond) or cold (hydraulic set) application and its setting speed.
- Refractoriness Under Load (RUL): Must demonstrate a high RUL to confirm structural stability at EAF operating temperatures (1600°C to 1700°C).
Technical Guidance: Successful gunning relies on proper preparation of the hot lining surface (removing loose slag) and precise control of the water/air pressure ratio in the gunning machine. Gunning mixes should not be used as a substitute for a full reline, but rather as an essential campaign extension and maintenance tool.
✨ 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. |
