Introduction
The LL-finned Tube features a double-layered structure of steel tube and aluminum fins, and is used in boilers, heat exchangers, and waste heat recovery systems.
Features
More Robust Fins
The double-layer coating structure ensures a complete mechanical lock between the fins and the base tube, increasing the contact area by approximately 15–20% compared to the L-type design, resulting in greater stability under vibration and thermal cycling.
Corrosion Resistance
The fin root completely covers the base tube, preventing moisture and corrosive substances from entering the gaps and reducing crevice corrosion.
Suitable for Higher Temperature Conditions
The compacted structure offers enhanced heat resistance, allowing stable operation up to 260–300°C without the risk of fin warping or detachment.
Manufacturing Process
Double-Layer Coating and Pressing Process
Aluminum strips are formed and simultaneously pressed onto the base tube, achieving a full, gapless fit.
Base Tube Surface Pretreatment
The base tube undergoes degreasing and rust removal treatment to improve metal-to-metal contact quality.
Continuous Forming and Synchronous Winding
Fin forming and winding are completed simultaneously to ensure consistent spacing.
Finished Product Straightening and Quality Inspection
Each piece is straightened and its dimensions and fit are inspected.
Packaging and Shipping
The fins are protected from deformation and moisture by using film wrapping, partitions, and wooden crates. We support land transportation, sea transportation, and customer-specified logistics.
