Extruded Finned Tubes
Premium extruded finned tubes manufactured through a cold-forming extrusion process that creates an integral fin structure from the tube wall itself. Offering the strongest possible fin-to-tube bond with zero contact resistance — the definitive solution for high-temperature and severe thermal cycling applications.
Extrusion Forming Technology
The Extrusion Process — Integral Fin Formation
Extruded finned tubes are manufactured through a cold-forming extrusion process that creates fins directly from the base tube material. Unlike welded or wrapped fin types where the fin is a separate component attached to the tube, extrusion forms the fins as an integral part of the tube wall.
The process begins with a bare thick-walled tube (the “muff” or “sleeve”). This tube is passed through a series of rotating extrusion dies that progressively displace material from the outer surface, forming helical fins while maintaining a continuous smooth bore on the inside. The result is a single-piece, monolithic finned tube with no weld interface and no mechanical joint between the fin and the tube.
Base Tube Preparation
Thick-walled aluminum or copper tube is cut to length and cleaned
Extrusion Rolling
Rotating dies progressively displace material outward to form fins
Fin Height Control
Precision die adjustment ensures uniform fin height along the tube
Final Inspection
100% dimensional check and visual inspection
Why Extruded Finned Tubes Outperform Welded Types
Key Advantages of Integral Extruded Fins
Extruded finned tubes represent the premium tier of finned tube technology. The integral fin structure eliminates the fundamental weakness present in all welded and wrapped fin types: the fin-to-tube interface.
| Fin-to-Tube Bond | Integral — fins are part of the tube material itself, no mechanical or welded joint exists |
| Thermal Contact Resistance | Zero — perfect thermal path from fin tip to tube bore with no interface losses |
| Corrosion Resistance | Superior — no dissimilar metal interface, no weld HAZ, no crevice corrosion initiation points |
| Thermal Cycling Endurance | Unlimited — no differential thermal expansion stress at fin root since fin and tube are same material |
| Vibration Resistance | Excellent — monolithic structure withstands mechanical vibration without fin loosening |
| Service Life | 30+ years in normal operating conditions, significantly outlasting welded alternatives |
Material Options — Extruded Fin Configurations
The extrusion process is primarily applied to aluminum and copper materials due to their excellent cold-forming ductility. The table below summarizes standard extruded finned tube configurations, dimensional ranges, and typical application matches. Custom fin geometries and bi-metallic extruded tubes are available upon request.
| Tube Material | Fin Material | Tube OD Range | Fin Height Range | Fin Density | Max Temp | Typical Applications |
|---|---|---|---|---|---|---|
| ▸ Aluminum Extruded Finned Tubes (Most Common) | ||||||
| Aluminum 1050 / 1060 | Aluminum (Integral) | 15.9mm – 50.8mm | 5mm – 16mm | 8–12 FPI | 150°C | HVAC coils, air coolers, refrigeration condensers, heat pumps |
| Aluminum 3003 / 5052 | Aluminum (Integral) | 19.0mm – 50.8mm | 6mm – 16mm | 8–12 FPI | 180°C | Higher strength HVAC, automotive radiators, charge air coolers |
| Aluminum 6061 / 6063 | Aluminum (Integral) | 19.0mm – 38.1mm | 6mm – 14mm | 6–10 FPI | 200°C | Industrial air coolers, compressed air aftercoolers, process cooling |
| ▸ Copper Extruded Finned Tubes (Premium) | ||||||
| Copper C12200 (DHP) | Copper (Integral) | 12.7mm – 38.1mm | 4mm – 12mm | 9–14 FPI | 200°C | High-efficiency HVAC, data center cooling, heat pipe condensers |
| Copper C11000 (ETP) | Copper (Integral) | 12.7mm – 31.8mm | 4mm – 10mm | 9–14 FPI | 200°C | Premium refrigeration, medical equipment cooling, precision heat exchangers |
| ▸ Bi-Metallic Extruded Finned Tubes (Combined Performance) | ||||||
| Copper (inner) / Aluminum (outer) | Aluminum (Integral over copper liner) | 15.9mm – 38.1mm | 6mm – 14mm | 8–12 FPI | 180°C | HVAC with water compatibility, cooling towers, process water cooling |
| Stainless Steel (inner) / Aluminum (outer) | Aluminum (Integral over SS liner) | 15.9mm – 31.8mm | 6mm – 12mm | 8–11 FPI | 250°C | Corrosive fluid inside with air cooling outside, chemical process cooling |
| ▸ Standard Dimensional Range Summary | ||||||
| Tube OD Range | 12.7mm (1/2″) – 50.8mm (2″) | Consult for larger diameter feasibility | ||||
| Fin Height Range | 4mm – 16mm | Dependent on tube OD and material ductility | ||||
| Fin Density Range | 6 – 14 FPI (Fins Per Inch) | Higher densities possible for low-fin applications | ||||
| Maximum Tube Length | Up to 12 meters | Length dependent on tube diameter and handling equipment | ||||
Bi-metallic extruded tubes combine a corrosion-resistant inner liner (copper or stainless steel) with an aluminum outer fin structure. The aluminum is extruded over the inner tube, creating a mechanical bond with excellent thermal contact. This configuration provides the fluid compatibility of the inner material with the light weight and cost-effectiveness of aluminum fins.
Application Range & Industry Sectors
HVAC & Refrigeration
Extruded aluminum and copper finned tubes are the gold standard for air-source heat exchangers in commercial and industrial HVAC systems. The zero contact resistance and lightweight construction make them ideal for fin-and-tube coil designs in air handling units, chillers, and heat pumps.
- Air-Cooled Condensers: Aluminum extruded finned tubes provide maximum heat rejection with minimal air-side pressure drop for rooftop chiller and VRF system condensers.
- Evaporator Coils: Copper extruded finned tubes deliver superior refrigerant evaporation performance in DX cooling coils for commercial air conditioning.
- Heat Pump Coils: Integral fin construction withstands frequent defrost cycles and thermal reversals without fin loosening — a common failure mode for welded fin coils.
Data Centers & Precision Cooling
Data center cooling demands maximum reliability and energy efficiency. Extruded copper finned tubes are the preferred choice for precision cooling units where consistent thermal performance and zero degradation over time are non-negotiable requirements.
- CRAC/CRAH Units: Copper extruded finned tubes in computer room air handlers deliver stable cooling performance for mission-critical server environments.
- In-Row Coolers: Compact high-efficiency coils with high-fin-density extruded tubes maximize heat transfer in space-constrained data hall layouts.
- Free Cooling Systems: Aluminum extruded finned tubes in air-to-glycol free cooling coils enable year-round economizer operation with zero refrigerant usage.
Industrial Process Cooling & Automotive
In industrial manufacturing and automotive applications, extruded finned tubes provide robust, vibration-resistant cooling solutions that maintain peak performance under continuous operation andF