Electric Furnace Basic Gunning Mix
Electric Furnace Basic Gunning Mix is a family of basic, high-magnesia refractory mortars specifically designed to be applied pneumatically (shotcrete/gunned) onto the hot, working lining of Electric Arc Furnaces (EAF). Its purpose is to perform hot repair, rapidly patching worn spots, eroded slag lines, and impact zones during short furnace downtimes.
This fast-setting mix extends the life of the furnace lining, minimizes turnaround time, and is essential for lowering overall refractory consumption and maximizing steel production continuity.
Main Function and Characteristics
The primary function is Rapid Hot Repair and Maintenance. The mix is usually composed of Magnesia (MgO) or Dolomite aggregates and uses chemical or hydraulic bonding mechanisms that ensure rapid setting and strong adherence to the hot, pre-existing basic refractory brick.
| Characteristic | Value Range | Primary Refractory Function |
|---|---|---|
| Material Base | Magnesia (MgO) / Dolomite (MgO-CaO) | Basic chemistry ensures compatibility and chemical stability in the EAF environment |
| Application Method | Gunning (Pneumatic) | Allows for remote, rapid application onto hot surfaces |
| Rebound Rate | LOW | Optimized grain sizing minimizes material loss during application |
Classification
- Material Focus: Monolithic Refractory
- Primary Application Focus: Hot Patching Compound → Electric Arc Furnace (EAF) Slag Line and Hot Spot Repair
Key Performance Metrics
- Setting Speed: VERY FAST — Must set and bond quickly to minimize tap-to-tap cycle time
- Hot Strength: HIGH — Maintains mechanical integrity immediately after application at operating temperatures
- Corrosion Resistance: EXCELLENT — Basic chemistry resists the corrosive action of high-basicity steelmaking slag
Electric Furnace Basic Gunning Mix
1. The Role of Gunning in EAF Maintenance
Electric Arc Furnaces operate under extreme thermal stress, turbulent stirring, and aggressive basic slags. The slag line and “hot spots” opposite the electrodes wear out rapidly.
- Minimizing Downtime: Gunning mixes enable steelmakers to perform maintenance during short periods between heats without cooling the furnace entirely. A pneumatic gun sprays the dry mix (or pre-dampened mix) onto the worn surface, where heat catalyzes the setting process.
- Basic Chemistry Compatibility: Since EAF linings are typically built from basic (Magnesite or Dolomite) brick, the gunning mix must also be basic (MgO-rich) to ensure chemical compatibility and prevent spalling.
2. Composition and Bonding Mechanisms
The formulation of an EAF gunning mix is engineered for performance on hot surfaces:
- Aggregate: High-purity sintered MgO (Magnesite) or MgO/CaO (Dolomite) resists high operating temperatures (up to ~1800°C) and slag attack.
- Bonding System: Must adhere instantly to the hot substrate. Common systems include:
- Chemical Bonds: Phosphate or sulfate binders that set rapidly when heated
- Ceramic Bonds: Low-melting silicates that fuse partially upon contact with the hot furnace wall, forming a strong ceramic bond
- Grain Sizing: Optimized to minimize rebound (material bouncing off the wall), ensuring maximum material retention on the repair area
3. Applications
- Slag Line Repair: Most frequent application, as the slag line is the most aggressively attacked area
- Bottom and Bank Patching: Repairs erosion in the furnace hearth and lower sidewalls
- Tap Hole Maintenance: Maintains integrity and shape of the tapping spout for safe metal pouring
- Secondary Vessels: Also used for hot patching of basic linings in steel ladles and converters
✨ 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. |
