Place of Origin:
Zhejiang/China
Brand Name:
TORICH
Certification:
ISO9001 ISO 14001 TS16949
Model Number:
L Finned Tube
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The product is a tension-wound finned tube of the “L-Foot” style, meaning that the fin strip is pre-formed into an “L” shaped foot and helically wound around a base tube under tension. This results in a strong mechanical bond between fin and tube and enhanced heat-transfer performance.
The base tube is made of alloy steel, making it suitable for higher strength, higher temperature, or more demanding environments than simple carbon steel finned tubes.
Base tube material: Alloy steel (can include carbon-moly, chrome-moly alloy or other alloy steel grades) as specified by the customer.
Fin material: Typically aluminum or copper strip formed into an L-foot profile and wound under tension onto the tube.
Tube outer diameter (typical range): ~0.5″ to ~2″ (12.7 mm to ~50.8 mm) for L-Foot tension wound fin tubes.
Fin height: up to ~16 mm (for L-Foot type).
Fin thickness: around 0.15 mm to 0.6 mm for typical L-type fin tubes.
Fin pitch: 6 to 12 fins per inch (~2.4 to ~4.8 mm fin spacing).
Length: Custom according to design requirement.
Temperature limit: Typical up to ~130 °C (≈270 °F) for basic L-foot fin tubes.
The L-foot profile offers a broad contact area between fin and tube, improving heat conduction.
Tension-wound fins ensure a firm mechanical bond, resisting loosening under vibration or thermal cycling.
Alloy-steel core tubes provide higher strength and improved temperature capability versus plain carbon steel.
Full fin coverage helps protect the tube surface from external corrosion.
Enhanced durability and reliability — Customers often worry about fins loosening over time. The L-foot tension-wound construction prevents this by ensuring consistent mechanical bonding.
Improved heat-transfer efficiency — Larger fin-to-tube contact area and tighter winding improve performance, often raising efficiency significantly over standard tension-wound designs.
Corrosion protection — Continuous fin coverage and tight adhesion reduce air-side corrosion of the base tube, increasing service life.
Material flexibility — Both the alloy-steel tube and fin material can be customized for temperature, corrosion, or mechanical requirements.
Cost-effective — Compared with extruded or welded fin tubes, L-Foot tension wound tubes provide excellent performance at a more economical cost level.
| Grade | C (%) | Mn (%) | Si (%) | Cr (%) | Mo (%) | Other (%) |
|---|---|---|---|---|---|---|
| ASTM A335 P9 | 0.10–0.15 | 0.30–0.60 | 0.50 max | 0.50–1.20 | 0.44–0.65 | V, Ti, Al |
| ASTM A335 P11 | ~0.08 | 0.29–0.60 | 0.50 max | 1.00–1.50 | 0.37–0.60 | V, Nb |
| ASTM A335 P22 | ~0.10 | 0.29–0.60 | 0.50 max | 2.00–2.50 | 0.85–1.03 | V, Nb |
| ASME SA179 | ≤0.30 | 0.27–0.63 | 0.10–0.35 | 0.40 max | — | — |
| ASTM A192 | ≤0.35 | 0.27–0.63 | 0.10–0.35 | 0.30–0.80 | ≤0.50 | — |
| Grade | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) |
|---|---|---|---|
| ASTM A335 P9 | ~415 | ~205 | ≥30 |
| ASTM A335 P11 | ~415 | ~205 | ≥30 |
| ASTM A335 P22 | ~415 | ~205 | ≥30 |
| ASME SA179 | ~415 | ~205 | ≥30 |
| ASTM A192 | ~415 | ~205 | ≥30 |
Relevant execution standards for this product include:
Base tube: ASTM A335 (P9, P11, P22), ASME SA179, ASTM A192, etc.
Fin materials: Aluminum according to ASTM B209; Copper according to ASTM B152.
Production specification: Tension-wound L-Foot fin profile, helical wrapping, mechanical locking.
Testing: Hydrostatic or pneumatic tests, fin adhesion verification, dimensional inspection.
General uses: Heat exchangers requiring increased surface area and higher-performance alloy-steel tubes.
Specific applications include:
Power plants: Air-cooled condensers, air preheaters, waste-heat recovery units.
Oil & Gas / Petrochemical: Refinery coolers, process gas coolers, heat-recovery systems.
HVAC and refrigeration: Condensers, evaporators, industrial air coolers.
Chemical and food industry: Dryers, heaters, coolers for gas-side heat exchange.
Marine and offshore: Air coolers exposed to corrosive marine conditions.
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A: manufacturer,also can do trading.
A: Generally speaking,it is 10-15 days if the goods are in stock,or it is 30-40 days if the goods are not in stock,
it is according to quantity.
A: Yes, we could offer the sample for free charge but need pay the cost of freight.
A: Payment<=2000USD, 100% in advance. Payment>=2000USD, 30% T/T in advance ,balance before shippment.
If you have another question, pls feel free to contact with me.
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