Finned Stainless Steel Coiltube for Mine Roadway Cooling Systems
Product Code: No. 1581 | Manufacturer: Wenzhou Jixing Metal Materials Co., Ltd.
Product Overview
The Finned Stainless Steel Coiltube is a precision-engineered heat exchange component designed primarily for underground mine roadway cooling and ventilation systems. Drawing upon advanced German engineering principles—specifically those documented in the technical literature regarding Performance of Finned Coiltubes and Spray Coolers Used in West German Mine Roadways—this product delivers superior thermal transfer efficiency in high-temperature, high-humidity subterranean environments.
Coiltubes, also referred to as coil tubing or finned coil assemblies, are integral to mine climate control systems. They function as the core heat exchange elements within cooling units, transferring thermal energy from the ambient mine air to a refrigerant or chilled water circuit. The coiled configuration maximizes the heat exchange surface area within a compact footprint, making them ideal for confined mine roadway installations.
Material & Properties
The coiltube is manufactured using high-grade stainless steel, selected for its exceptional resistance to corrosion, mechanical durability, and thermal stability in harsh mining environments.
- Base Material: Austenitic stainless steel (e.g., AISI 304 / AISI 316L), providing excellent resistance to sulfide-containing mine atmospheres and moisture.
- Fin Material: Aluminum or stainless steel fins, depending on the thermal conductivity requirements and corrosion environment.
- Corrosion Resistance: Withstands aggressive mine gases including hydrogen sulfide (H₂S), carbon dioxide (CO₂), and moisture-laden air.
- Mechanical Strength: Maintains structural integrity under vibration, pressure cycling, and thermal expansion loads.
- Thermal Conductivity: Optimized for efficient heat transfer between the process fluid and ambient air.
- Temperature Range: Suitable for continuous operation from -20 °C to +120 °C.
Specifications
| Parameter | Specification |
|---|---|
| Tube Material | AISI 304 / 316L Stainless Steel |
| Tube Outer Diameter (OD) | 10 mm – 25 mm (customizable) |
| Tube Wall Thickness | 0.5 mm – 2.0 mm |
| Coil Diameter | 150 mm – 600 mm |
| Fin Pitch | 2.0 mm – 5.0 mm |
| Fin Thickness | 0.1 mm – 0.3 mm |
| Effective Heat Transfer Area | Up to 15 m² per coil assembly |
| Operating Pressure | Up to 1.6 MPa (gauge) |
| Refrigerant Compatibility | R-134a, R-410A, Ammonia (NH₃), Chilled Water |
| Surface Treatment | Pickled & Passivated (P&P) / Electropolished |
| Standard Reference | ASTM A213 / EN 10216-5 / DIN 17475 |
Manufacturing Process
The production of finned stainless steel coiltubes follows a rigorous multi-stage manufacturing process to ensure dimensional accuracy, mechanical integrity, and thermal performance:
- Raw Material Inspection: Incoming stainless steel tubes undergo spectroscopic analysis to verify chemical composition compliance with ASTM/EN standards.
- Tube Forming & Coiling: Precision tube-bending machinery forms the straight tubes into helical coils with controlled coil diameter and pitch, utilizing CNC-controlled mandrel bending to prevent ovality and kinking.
- Fin Attachment: Fins are applied via either mechanical expansion (roll-fin) or braze-bonding processes. Roll-fin technology ensures intimate metal-to-metal contact between fins and tubes, maximizing thermal conductivity and eliminating thermal resistance gaps.
- Welding & Joining: Inlet and outlet headers are welded to the coil ends using TIG (Tungsten Inert Gas) welding or orbital welding, ensuring leak-tight joints capable of withstanding system pressure.
- Surface Treatment: The assembled coiltube undergoes pickling and passivation to remove welding discoloration, restore the chromium oxide protective layer, and enhance corrosion resistance.
- Pressure Testing: Each unit is hydrostatically tested at 1.5 times the maximum operating pressure to verify structural integrity and weld soundness.
- Final Quality Inspection: Dimensional verification, visual inspection, and performance benchmarking against design specifications.
Applications
Finned stainless steel coiltubes from Wenzhou Jixing Metal Materials Co., Ltd. are deployed across a broad spectrum of industrial cooling applications:
- Mine Roadway Cooling: The primary application domain—installed in mine ventilation ducts to cool ambient air and maintain safe working temperatures in deep underground operations where geothermal heat raises temperatures to 35 °C and above.
- Industrial HVAC Systems: Used in commercial and industrial air conditioning units requiring corrosion-resistant heat exchange elements.
- Refrigeration Systems: Employed as evaporator coils in cold storage, food processing, and pharmaceutical cooling installations.
- Heat Recovery Units: Integrated into energy recovery systems for waste heat capture and redistribution.
- Chemical Processing: Applied in cooling circuits for chemical reactors and distillation columns where stainless steel corrosion resistance is mandatory.
Quality Certifications & Compliance
Wenzhou Jixing Metal Materials Co., Ltd. maintains rigorous quality management systems and holds the following certifications to ensure product reliability and international compliance:
- ISO 9001:2015 — Quality Management System certification ensuring consistent product quality and continuous improvement.
- ISO 14001 — Environmental Management System certification demonstrating commitment to sustainable manufacturing practices.
- CE Marking — Conformity with European health, safety, and environmental protection standards, facilitating export to European markets.
- Material Traceability: Full batch traceability from raw steel mill certificates (MTC — Material Test Certificate, EN 10204 3.1) through to finished product.
- Third-Party Inspection: Available upon request from recognized inspection bodies (e.g., SGS, BV, TÜV) for critical installations.
Unique Selling Points
The finned coiltube product line from Wenzhou Jixing Metal Materials Co., Ltd. distinguishes itself through the following key advantages:
- German Engineering Heritage: Product design principles are informed by proven West German mine cooling technology, validated through decades of operational data in demanding underground environments.
- Superior Corrosion Performance: 316L stainless steel construction provides unmatched resistance to sulfide corrosion prevalent in mining atmospheres, significantly extending service life compared to carbon steel alternatives.
- High Surface-to-Volume Ratio: The finned coil geometry achieves up to 8–12 times the heat transfer surface area of bare tubes, delivering compact, high-efficiency cooling solutions.
- Customization Capability: Flexible design parameters (tube diameter, coil pitch, fin density, overall dimensions) allow tailored solutions for specific mine ventilation layouts and cooling load requirements.
- Low Maintenance: Stainless steel construction eliminates the need for anti-corrosion coatings or regular replacement, reducing lifecycle costs in inaccessible underground installations.
- Environmental Responsibility: High thermal efficiency translates to reduced refrigerant charge and lower energy consumption, supporting sustainable mining operations.
Technical Notes
Based on the study of Performance of Finned Coiltubes and Spray Coolers Used in West German Mine Roadways, it is well established that finned coil cooling systems, when properly designed and installed, can reduce mine roadway temperatures by 8–15 °C compared to unconditioned air. The coiltube serves as the critical interface between the cooling medium and the mine atmosphere, and its thermal performance directly determines the effectiveness of the entire cooling system. Proper selection of fin density, tube material, and coil geometry is essential to balance thermal efficiency against pressure drop across the coil assembly, ensuring optimal airflow through the mine ventilation system.
Wenzhou Jixing Metal Materials Co., Ltd. offers comprehensive technical support, including thermal load calculations, system integration guidance, and post-installation performance verification to ensure customers achieve maximum cooling efficiency from their coiltube installations.