What is a Finned Tube
A finned tube is used as heat exchanger tube with spiral or longitudinal fins to increase external surface area and improve heat exchanger efficiency. It is a high-efficiency heat transfer element with metal fins added to the outer wall of a plain tube. It is featured with high heat exchange efficiency and enhances air-side turbulence, and is widely used in boilers, economizers, air preheaters, air coolers, condensers, and various heat exchange equipment. Finned tubes can be classified by different methods.
| Base Tube (Tube) | Fin (Fin Material) | Surface Treatment (Coatings) |
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Finned Tube Classification:
- Based on manufacturing processes, there arer high-frequency welded finned tubes, spiral wound finned tubes, extruded finned tubes, and cast finned tubes, etc.;
- According to fin shape, they can be classified into helical finned tubes, longitudinal finned tubes, and serrated finned tubes, etc.
AGICO supplies finned tubes with the characteristics of compact structure, high heat transfer efficiency, good corrosion resistance, and long service life,
Metal Material Types for Finned Tube Manufacture
Finned tubes can be manufactured from 1 or 2 metal types, called single-metal and bimetal finned tubes.
Bimetal finned tubes manufacture method example: aluminum fins mechanically bonded or extruded onto a steel or copper tube—combining high thermal conductivity with excellent corrosion resistance.
Single metal finned tubes are fabricated from the same material for both the base tube and fins, ensuring uniform mechanical and thermal properties
Finned Tube Materials
- Single metal finned tube: both base tube and fin are made of copper, aluminum, carbon, or stainless steel.
- Bimetal finned tube: Common metal matches are: Aluminum fins + Steel tube; Copper fins + Stainless steel tube; Aluminum fins + Copper tube.
Hot Sale Finned Tubes Supplied by AGICO
Various types of finned tubes are manufactured and supplied by AGICO for high-efficiency heat transfer solutions, such as in air coolers, boilers and waste-heat recovery. We supply HFW welded finned tube, embedded G-type finned tube, L/LL/KL fin tube, extruded fin tube and serrated finned tube designs, covering OD 19–63.5 mm, 5–11 FPI and fin heights 8–16 mm. Metal materials include carbon steel, stainless steel, aluminum and copper. Our finned tubes are supplied according to API 661/TEMA practice, 100% hydro-tested with fin bond inspection. Customer can have custom lengths, U-bends and corrosion-resistant coatings and other fabrication options.
Finned Tube Specifications:
- Tube outer diameter (OD): 19–63.5 mm (commonly 25.4/31.75/38.1 mm)
- Wall thickness (WT): 2.0–5.0 mm (depending on pressure and welding process)
- Fin height: 8–16 mm (higher for steel fins)
- Fin thickness: 0.3–1.5 mm
- Fin density per inch (FPI): 5–11 FPI (or 170–350 fins per meter)
- Finning length: As per drawings (leave unfurled sections at both ends for expansion/welding)
- Straight or U-bend: Both can be customized
Note: The above are common ranges; the engineering specifications shall prevail based on the drawings/working conditions.
Finned Tube Types for Heat Exchangers
AGICO supplies wide ranges of finned tube fabrication for heat exchange tubes, check the following types, if you want to buy finned tubes, contact us now for free quote!
Embedded Fin Tube – L/LL/KL/G
Introduction: Embedded Finned tubes are supplied in 4 grades: L, LL, KL type fin tubes and G type finned tube. Base tube can be carbon steel tubes, stainless steel tubes or copper tubes. The tube diameter is typically 25-100mm, and the wall thickness is 2-5mm. The base tube needs to be pickled and polished to remove the surface oxide layer.
The Embedding Process have 2 methods:
- High-frequency welding: The fin root and base tube are instantaneously fused at a high temperature of 800-1000℃, with a welding speed of 3-10m/min (refer to ASME B31.1 standard).
- Cold Press Embedding: The fins are pressed into a pre-set groove in the base tube using a hydraulic press. Use pressure ( 50-100MPa ) to ensure the bonding strength.
Extruded Finned Tubes
Introduction: AGICO supplies extruded fin tubes in 4 types: aluminum finned steel tube, aluminum finned copper tube, and aluminum and copper extruded fin tube.
Metal Materials: Base tube can be carbon steel tubes, stainless steel tubes or copper tubes. Outer sleeve material is usually aluminum (AA1060、AA3003). Base tube shall be degreased and cleaned.
The extrude process::
- The aluminum sleeve (aluminum cylinder) is tightly assembled onto the outer surface of the base tube. Both tubes ends are positioned to ensure no gaps or slippage.
- The tube assembly is fed into an extrusion finning machine. Fin is formed by the aluminum sleeve hot-extruded under high temperature (approximately 350–400°C) and high pressure conditions.
Welded Finned Tube
Introduction: According to the welding method, welded finned tubes can be manufactured in the following methods: （HFW） high-frequency welded fin tube, arc welded fin tube, submerged arc welded fin tube and laser welded fin tube. AGICO mainly supplies longitudinal fin tube, spiral welded fin tube and also serrated finned tube.
Welded Finned Tubes Features:
- High-Frequency Welded Fin Tube: Featured with uniform weld seam, good thermal conductivity, and high efficiency. Used in boilers, economizers, and air coolers.
- Arc Welded Fin Tube: Suitable for thick-walled or high-temperature applications, for example industrial boilers and heating furnaces.
- Submerged Arc Welded Fin Tube: It has high-quality weld seam and can be widely used in large-scale high-pressure heat exchange equipment.
- Laser Welded Fin Tube: It has a small heat-affected zone, suitable for stainless steel and high-alloy materials for high-end petrochemical equipment.
Finned Tube Applications and Market
Finned tubes from AGICO are the key parts in heat exchange solutions in many industrial applications. We supply high-end finned tubes meeting the demanding requirements of various working conditions, covering high temperatures to corrosive environments.
Finned Tube For Heat Exchange Tube
Finned Tubes Applications
Finned tubes are widely used in the following industries where heat exchangers are used, in other word, it is the basic element – heat exchanger tube.
- Petrochemical Industry
- Oil Refining and Natural Gas
- Power Industry:
- HVAC and Refrigeration:
- Industrial Processing:
- Compressed Air Systems
Main Market of Finned Tubes – AGICO
Finned tubes from AGICO have been exported to the Middle East and Gulf Region, North America, Europe, Southeast Asia, and India, etc. Our finned tube products have maily engaged in 4 core industries: oil and gas, refining, power, chemicals, and HVAC&R, which have a continuous and substantial demand for efficient and reliable heat exchange solutions. If you are interested in a customized finned tube solution, send your request to AGICO now for free!
- Middle East and Gulf Region: AGICO supplies high-end finned tubes for oil and gas exploration and petrochemical projects.
- North America: AGICO offers customized finned tubes for heat exchange solutions for oil and gas industry, power facilities, and a large HVAC market.
- Europe: High-end Finned tubes for chemical and power plant upgrade, also waste heat recovery projects.
- Southeast Asia and India: Large quantities of finned tubes are exported for growing number of refining plant and power plant.
Why Choose AGICO
AGICO is an experienced steel fabrication service supplier for all types of finned tubes, the quality of finned tubes are mainly guarranteed by the strict standards and quality and inspection controls.
National Standards
Finned tubes are manufactured strictly following API 661 (Air-cooled heat exchangers for the oil and gas industry), TEMA R/C/B (Shell-and-tube practices), ASTM/ASME/EN material and pressure testing standards (e.g., A179/A192/A213), and we can supply them according to PED/CE, CRN, and other regulations.
Quality Tests
Here are the necessary quality tests and inspections during finned tube manufacturing process:
- Hydrostatic testing (usually 1.3–1.5 × design pressure)
- Air-under-water leak test
- Eddy-current/PT, RT (as required)
- Fin bond & pull tests
- Dimensional & visual inspection
- Material traceability / MTC (EN10204 3.1/3.2)
