Extruded Aluminium Bi-Metallic Fin Tubes are produced by extruding an aluminium outer layer over a separate base tube to form a continuous tightly bonded fin surface. The aluminium coating offers good protection against atmospheric corrosion and at the same time ensures good heat transfer. The operating temperature for these tubes is up to 300°C and the fin density, fin height, tube OD and cut length can be tailored to the design of the heat exchanger. Carbon steel, stainless steel, duplex steel, and copper-nickel are among the metal alloys used to make the base tubes. Other metals used include titanium and nickel alloys. Manufactured in accordance with ASTM B359 and ASTM B891, inspection documentation is available per specified orders in accordance with EN 10204 3.1/3.2. Amardeep Steel is an established Extruded Aluminium Bi-Metallic Fin Tubes Manufacturer and Supplier in India, which is used in air coolers, condenser, heat exchangers, and process equipment.
Technical Data
Specifications of Extruded Aluminium Bi-Metallic Fin Tubes
Specification Parameter | Manufacturing Range / Technical Detail |
|---|---|
Base Tube Material Options | Carbon Steel, Alloy Steel, Stainless Steel (304/304L, 316/316L, 321, 347), Duplex & Super Duplex, Titanium, Copper Alloys (Cu-Ni 90/10, Cu-Ni 70/30), Nickel Alloys (Inconel, Hastelloy, Monel) |
Base Tube Outer Diameter (OD) | 15.88 mm to 50.80 mm (5/8" to 2") |
Base Tube Wall Thickness | 1.24 mm to 5.00 mm |
Fin Material | High-Purity Aluminium Alloys (Al 1060 / Al 1100 / Al 6063) |
Fin Height Range | 9.5 mm to 15.88 mm (3/8" to 5/8") |
Fin Thickness | 0.35 mm to 0.50 mm |
Fin Density / Pitch | 7 to 11 Fins Per Inch (FPI) / 275 to 433 Fins Per Meter (FPM) |
Maximum Operating Temp | Up to 300°C (572°F) continuous duty |
Fin Bond Mechanism | High-pressure Mechanical Cold Extrusion (100% Core Encapsulation) |
Tube Length Capability | Up to 18 meters (Straight lengths or custom bent) |
Testing & Inspection | Hydrostatic Testing, Pneumatic Testing, Eddy Current Testing, Fin Bond Pull-Off Strength Test, Dimensional Verification |
Chemical Compositions of Extruded Aluminium Bi-Metallic Fin Tubes
Material Component | Alloy Grade | Al (%) | Cu (%) | Fe (%) | Si (%) | Mn (%) | Mg (%) | Zn (%) | Ti (%) | Other / Remainder |
|---|---|---|---|---|---|---|---|---|---|---|
Outer Fin Sleeve | Al 1060 | ≥ 99.60 | ≤ 0.05 | ≤ 0.35 | ≤ 0.25 | ≤ 0.03 | ≤ 0.03 | ≤ 0.05 | ≤ 0.03 | V ≤ 0.05%, Each ≤ 0.03% |
Outer Fin Sleeve | Al 1100 | 99.0–99.95 | 0.05–0.20 | ≤ 0.95 | ≤ 0.95 | ≤ 0.05 | — | ≤ 0.10 | — | Residuals ≤ 0.15% |
Base Tube (Carbon Steel) | ASTM A179 | — | — | Bal. | — | 0.27–0.63 | — | — | — | C: 0.06–0.18%, P/S ≤ 0.035% |
Base Tube (Stainless Steel) | TP316 / 316L | — | — | Bal. | ≤ 0.75 | ≤ 2.00 | — | — | — | Cr: 16–18%, Ni: 10–14%, Mo: 2–3% |
Base Tube (Cu-Ni) | Cu-Ni 90/10 | — | Bal. | 1.0–1.8 | — | 1.0 max | — | — | — | Ni: 9.0–11.0%, Pb ≤ 0.02% |
Extruded Aluminium Bi-Metallic Fin Tubes Mechanical Properties
Component / Material | Standard / Temper | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) | Hardness (HB / HRB) | Density (g/cm³) |
|---|---|---|---|---|---|---|
Al 1060 Fin Sleeve | Annealed (O) / Extruded | 58 – 95 | ≥ 17 – 28 | 15 – 43 | 19 HB | 2.705 |
Al 1100 Fin Sleeve | H12 / H14 (Half-Hard) | 110 – 145 | 100 – 125 | 9 – 12 | 28 – 32 HB | 2.71 |
Carbon Steel Core | ASTM A179 / SA179 | ≥ 325 | ≥ 180 | ≥ 35 | ≤ 72 HRB | 7.85 |
Stainless Steel Core | ASTM A213 TP316L | ≥ 485 | ≥ 177 | ≥ 35 | ≤ 90 HRB | 8.00 |
Copper-Nickel Core | ASTM B111 C70600 | ≥ 275 | ≥ 105 | ≥ 30 | ≤ 45 HRB | 8.94 |
Equivalent Standards of Extruded Aluminium Bi-Metallic Fin Tubes
Standards & Certifications | Fin Tube Standards | Quality & Inspection Certifications | Base Tube Standards |
|---|---|---|---|
Applicable Standards | ASTM B359 / B891 | EN 10204 – 3.1 / 3.2 Certification | Additional standards per base tube requirement (ASTM, ASME, DIN, etc.) |
Dimensions Chart of Extruded Aluminium Bi-Metallic Fin Tubes
Base Tube OD (mm) | Base Tube Wall (mm) | Fin Height (mm) | Fin Thickness (mm) | Approx. Finned OD (mm) | Weight (Kg/M) |
|---|---|---|---|---|---|
15.88 (5/8") | 1.24 – 1.65 | 9.5 – 12.7 | 0.35 – 0.50 | 34.9 – 41.3 | 0.75 – 1.15 |
19.05 (3/4") | 1.65 – 2.11 | 12.7 – 15.9 | 0.40 – 0.50 | 44.5 – 50.8 | 1.10 – 1.65 |
25.40 (1") | 1.65 – 2.77 | 12.7 – 15.9 | 0.45 – 0.55 | 50.8 – 57.2 | 1.45 – 2.30 |
38.10 (1 1/2") | 2.11 – 3.20 | 15.9 – 19.05 | 0.50 – 0.60 | 69.9 – 76.2 | 2.40 – 3.75 |
50.80 (2") | 2.77 – 4.00 | 15.9 – 25.4 | 0.50 – 0.65 | 82.6 – 101.6 | 3.80 – 6.10 |
Selecting a base tube material for your air-cooled exchanger? Send us your operating temperature and gas composition and we'll recommend the right base-tube alloy and fin height.
Applications and Industrial Uses of Extruded Aluminium Bi-Metallic Fin Tubes
- Air Cooled Heat Exchangers
- Fin-Fan Coolers
- Process Heat Exchangers
- Condensers
- Oil Coolers
- Gas Coolers
- Refinery Cooling Systems
- Petrochemical Heat Recovery Systems
Frequently Asked Questions
What are Extruded Aluminium Bi-Metallic Fin Tubes?
They are finned tubes made by extruding an aluminium outer layer over a separate base tube, creating a strong bond and an increased heat-transfer surface.
What are the advantages of Extruded Aluminium Bi-Metallic Fin Tubes?
They offer good heat transfer, atmospheric corrosion resistance, mechanical strength, and flexibility in selecting the base tube material.
How do extruded fin tubes improve heat transfer?
The aluminium fins increase the external surface area of the tube, allowing more heat to transfer between the tube and surrounding air or fluid.
What is the difference between monometallic and bi-metallic fin tubes?
Monometallic fin tubes use one metal for the tube and fins, while bi-metallic fin tubes combine two different metals, such as a steel base tube with aluminium fins.
Are Extruded Aluminium Bi-Metallic Fin Tubes suitable for air coolers?
Yes. Their large finned surface area and aluminium outer layer make them suitable for air-cooled heat exchangers and fin-fan coolers.
Can extruded aluminium fin tubes be used in condensers?
Yes. They can be used in air-cooled condensers where efficient heat dissipation and atmospheric corrosion resistance are required.
