As a high-efficiency heat exchange element, the core of inserted fin tubes lies in embedding metal strips into the spiral grooves on the surface of the base tube through a mechanical insertion process, thereby achieving a significant expansion of the heat exchange surface area. This process not only improves heat transfer efficiency but also balances cost and applicability, making it widely used in multiple industrial fields.

 

The manufacturing of inserted fin tubes begins with base tube pretreatment. First, spiral grooves of specific specifications are prefabricated on the outer surface of the base tube, with strict tolerance control for groove depth and width (usually within ±0.2mm) to ensure tight embedding of the metal strips. Subsequently, using specialized equipment, pre-tightening force is applied to spirally wind and press the metal strips (commonly made of aluminum, copper, or stainless steel) into the grooves. Finally, welding fixation is performed at both ends of the metal strips to ensure structural stability. Throughout the process, the issue of contact surface misalignment due to material springback must be avoided, with side gap control being a key link.

 

1. Efficient Heat Exchange: The fin structure significantly increases the heat exchange surface area, improving heat transfer efficiency by over 50% compared to smooth tubes, especially suitable for working conditions with small temperature differences.

2. Mechanical Stability: The insertion process forms a mechanical interlock, with no welds between the fins and the base tube, resulting in strong vibration resistance. However, attention should be paid to potential loosening at high temperatures due to differences in thermal expansion.

3. Cost and Economy: Compared to welding or integral rolling processes, insertion technology has lower equipment requirements and higher material utilization, with a single tube processing cost of only 1/3 to 1/2 that of welding.

4. Customized Design: The base tube material (such as carbon steel, stainless steel), fin size, and arrangement can be adjusted according to actual needs, adapting to different temperature, pressure, and medium conditions.

 

Inserted fin tubes are mainly used in industrial heat exchange scenarios, including:

- Power Industry: Boiler waste heat recovery systems, air preheaters;

- Chemical and Metallurgical Industry: Reactor cooling, flue gas heat exchange;

- Refrigeration Equipment: Air-cooled condensers, evaporators;

- Environmental Protection Field: Heat recovery devices in waste gas treatment systems.

 

Despite the significant advantages of inserted fin tubes, their production efficiency is relatively low, and extremely high tolerance requirements are imposed on groove-strip. Improper tolerance control may lead to reduced heat conduction performance or fin loosening. Future optimization directions include:

- Developing high-precision groove cutting equipment to reduce manual intervention;

- Adopting composite processes (such as local welding after insertion) to improve reliability under high-temperature conditions;

- Introducing automated production lines to increase production capacity and meet large-scale demand.

 

Overall, inserted fin tubes achieve a balance between heat exchange efficiency and cost through the mechanical insertion process. Although they have limitations in certain extreme working conditions, they remain one of the mainstream choices in the industrial heat exchange field.