SiC Tube (Process / Furnace)
Main Chemical Compositions & Categories
SiC Tubes are manufactured from high-purity SILICON CARBIDE (SiC). They are produced using various bonding techniques depending on the required temperature limit, gas tightness, and chemical environment.
| CATEGORY | BONDING / MANUFACTURING | PRIMARY USE | MAX. TEMP. LIMIT |
| Recrystallized SiC (ReSiC) | SiC to SiC bond | High-purity process tube/sheath | ~1650°C |
| Reaction-Bonded SiC (RBSiC}$) | SiC bonded with residual Si | Structural/Radiant tube/Sheath | ~1400°C |
| Nitride-Bonded SiC (NBSiC) | SiC bonded with Si3N4 | High strength/Chemical resistance sheath | ~1650°C |
Key Properties and Performance
| PROPERTY | TYPICAL PERFORMANCE | MECHANISM OF ADVANTAGE |
| Gas Tightness / Impermeability | EXCELLENT | Dense bonds (RBSiC or ReSiC) achieve near-zero porosity, protecting internal components/atmosphere. |
| Thermal Shock Resistance | OUTSTANDING | High thermal conductivity (Tc) and low coefficient of thermal expansion (CTE) prevent cracking during rapid temperature changes. |
| Corrosion/Erosion | EXCELLENT | Highly resistant to aggressive furnace atmospheres, acid/alkali vapors, and molten metal splashes. |
| Hot Strength | HIGH | Maintains rigidity and minimal sag or deformation at extreme operating temperatures. |
Advantages and Key Characteristics
SiC Tubes are critical components in thermal systems that require protection, heat transfer, or structural support under extreme operating conditions.
- High-Purity Isolation: In thermocouple protection applications, the tube isolates the sensitive measuring junction from the harsh furnace atmosphere, preventing contamination and chemical attack, thereby ensuring accurate and reliable temperature readings.
- Efficient Heat Transfer: Used as a radiant tube, SiC‘s high thermal conductivity ensures that heat from the internal burner/element is rapidly and uniformly transferred to the furnace chamber, maximizing heating efficiency and process uniformity.
- Dimensional Stability: The tubes exhibit exceptional creep resistance and minimal thermal expansion, maintaining straightness and dimensional integrity over long spans and extended service life.
- Resistance to Wear: The high hardness of SiC makes the tube surface highly resistant to abrasive dust, particle flow, and erosion from high-velocity gases.
Typical Industries and Applications
SiC Tubes are widely used in critical furnace systems:
- Metallurgical Industry: Radiant heater tubes for indirect heating of controlled atmosphere furnaces (e.g., annealing, galvanizing), and protection tubes for thermocouples submerged in molten metal (aluminum, zinc).
- Chemical Industry: Process tubes for carrying aggressive gases at high temperatures; components for gas cleaning and heat exchange.
- Ceramics Industry: Structural supports, peep-sight tubes, and gas sampling tubes in kilns.
Furnace Areas and Service Zones
They are specified for structural roles within the hot zone or for isolation:
- THERMOCOUPLE SHEATHS: Submerged in molten metal or placed in direct contact with the hottest gases.
- RADIANT HEATER SYSTEMS: The outer tube encasing the heating element or gas burner, protecting the furnace atmosphere from the combustion/element gases.
- GAS SAMPLING PORTS: Used to draw representative gas samples from the hot zone without introducing air or contamination.
Key Data Sheet Properties to Consider
Selection criteria focus on thermal properties and resistance to environment:
- Wall Thickness and Diameter: Must be specified to balance thermal transfer efficiency (thinner wall) with mechanical strength/protection needs (thicker wall).
- Thermal Conductivity (Tc): High Tc is essential for radiant tubes; moderate Tc may be acceptable for protection tubes.
- Gas Tightness/Permeability: CRITICAL VALUE. Must be checked, especially for protection or process tubes operating in vacuum or controlled atmospheres. RBSiC is generally best for gas-tightness up to 1400°C.
- Atmosphere Compatibility: The specific SiC bond (e.g., RBSiC vs. ReSiC) must be compatible with the process atmosphere and maximum temperature (e.g., RBSiC is limited in certain highly reducing or high-vacuum environments above 1400°C).
Technical Guidance: For submerged molten metal applications, the SiC tube must be pre-heated slowly before immersion to avoid catastrophic thermal shock failure. Regular inspection of the tube end is necessary to check for wear or material deposition.
✨ 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. |
