Carbon Steel U Bend Solid Finned Tube, High Frequency Welded Fin With A106 Gr.B Pipe Used In Economizer​

High-frequency welded spiral finned tube is a kind of tubular high-efficiency heat transfer element with spiral fins.The extended surface (fin) can be solid or serrated, and its heat transfer area is dozens of times larger than that of bare tube.

High-frequency welding of spiral finned tube is to heat the outer surface of steel strip and steel pipe to plastic state or melting by using the skin effect and proximity effect of high-frequency current while the steel strip is winding the steel pipe, and complete the welding under a certain pressure of winding the steel strip. This high frequency welding is actually a solid phase welding. Compared with inlaying, brazing (or overall hot galvanizing) and other methods, it is more advanced in terms of product quality (high welding rate of fins, up to 95%), productivity and automation.

Features of HFW fin tube:

• Due to the high welding speed and strong self-cooling effect of the weldment, not only the heat affected zone is small, but also the oxidation is not easy to occur, so the structure and properties of the weld are very good.
• Anti-corrosion performance, wear resistance, low contact thermal resistance, high stability, and anti-ash ability.
• Large heat exchange area.

Why use finned tube?

• Improve the heat transfer efficiency in the effective space.
• Reduce the installation space of the required heat transfer surface
• Reduce the equipment cost and have high operation reliability.
• The pressure drop at the pipe side is reduced, and the operation cost is reduced.
• The rigidity and seismic performance of steel pipe are improved.
• Strengthen heat transfer, reduce flow resistance and metal consumption

Manufacturing Process

The steel fin is spiral wound and continuously welded on the steel pipe by high-frequency resistance welding (HFERW). High frequency current is introduced into the workpiece, the welding contact surface is melted or semi-melted by resistance heat, and then appropriate pressure is applied to the weld contact surface to complete the welding of the fin tube. This results in a uniform, clean and continuous finned tube with no additional welding material to combine very effective heat flow and corrosion resistance.
High-frequency welded spiral finned tube is one of the widely used spiral finned tubes, which is widely used in power, metallurgy, waste heat recovery in cement industry and petrochemical industry.

Applications of Carbon Steel U-bend Solid Finned Tube

1. Boiler & power plant: Economizers, air preheaters, waste heat recovery.

2. Petrochemical & oil refining: Heat exchangers, coolers, heaters for crude oil and process fluids.

3. Industrial heating & HVAC: Hot water/steam heating coils, drying systems.

4. Metallurgy & cement: Flue gas waste heat recovery units.

5. Marine: Engine jacket water coolers, oil coolers.