L-foot wound finned tubes are highly cost-effective heat transfer components offering exceptional thermal performance, making them ideal for air-cooled heat exchangers (ACHE), condensers, oil coolers, and various industrial cooling systems operating within low to medium temperature ranges. Built with ASME SA179 seamless carbon steel tubes and high-purity AL1060 aluminum fins, this extended surface configuration drastically increases the heat dissipation area to maximize heat transfer efficiency while maintaining excellent mechanical reliability.

The fin geometry features a precision-formed “L” shape base, which is spirally wrapped under controlled mechanical tension around the outer diameter (OD) of the base tube. This interlocking L-foot design ensures tight metal-to-metal contact, significantly reducing contact thermal resistance. Furthermore, because the adjacent fin feet overlap completely, they form a protective continuous sleeve over the SA179 tube surface, shielding it from direct atmospheric exposure and effectively minimizing external corrosion under proper operating conditions.

Thanks to its cost-effective design and reliable performance, the L-foot tension wound fin tube remains one of the most widely specified and commonly used configurations in the global air-cooled thermal equipment market today.

L-foot finned tubes are manufactured by mechanically wrapping a pre-formed aluminum strip around the outer diameter (OD) of the base tube. During the fabrication process, the aluminum strip is precisely formed into an “L” shape, and its foot is tightly tension-wound onto the base tube surface to ensure maximum metal-to-metal contact.

Unlike welded fin tubes, this cold-wrapping process requires no high-temperature welding, thereby fully preserving the original metallurgical properties of both the steel base tube and the aluminum fins.

This automated manufacturing process consistently delivers:

• Uniform Fin Pitch
• Consistent Fin Height
• Stable and Secure Fin Attachment
• Excellent Dimensional Accuracy
• Reliable Thermal Performance
• Smooth Outer Fin Surface

The low-carbon steel composition provides excellent thermal conductivity, formability, and weldability, making it suitable for heat exchanger service.

These properties ensure dependable structural performance under normal operating conditions.

The high aluminum purity contributes to exceptional thermal conductivity and excellent fin-forming characteristics.

These properties enable efficient heat transfer while maintaining flexibility during the winding process.

Each L-type wound finned tube undergoes rigorous inspection procedures throughout manufacturing to ensure product consistency and reliability.

• Mill Test Certificate verification
• Material traceability review
• Chemical composition validation
• PMI testing available upon request

• Tube outside diameter measurement
• Wall thickness verification
• Fin height inspection
• Fin pitch verification
• Length tolerance measurement
• Straightness checking

• Tensile testing
• Flattening test
• Expansion test
• Fin winding integrity evaluation

• Eddy current testing
• Hydrostatic pressure testing
• Pneumatic leak testing (if specified)
• Surface defect inspection

• Fin uniformity inspection
• Surface finish assessment
• Fin attachment verification
• Packaging inspection

Independent inspection services can be arranged through internationally recognized agencies such as SGS, TÜV, Bureau Veritas, Intertek, and Lloyd’s Register.