Aluminum embedded fin tubes (G-type or grooved fin tubes) differ significantly from other fin tube types (such as L-type wound tubes and bimetallic rolled tubes) in terms of structure, performance, and applicable scenarios.
1. Material
Steel-aluminum embedded fin tubes combine the advantages of both steel and aluminum.
Steel offers excellent strength and rigidity, capable of withstanding high pressure and stress, making them suitable for applications requiring high structural strength. Aluminum, on the other hand, possesses excellent thermal conductivity, effectively improving heat transfer efficiency and reducing thermal resistance. In contrast, fin tubes made of a single material may have performance limitations.
For example, while pure copper fin tubes offer excellent thermal conductivity, they are relatively weak, making them unsuitable for high-pressure or high-vibration environments. Aluminum alloy fin tubes are slightly weaker than steel-aluminum embedded fin tubes and may not meet requirements in some heavy-duty applications.
Aluminum embedded fin tubes: Heat transfer efficiency is approximately 20% higher than L-type fin tubes due to the close contact between the fins and the base tube, resulting in low thermal resistance.
Aluminum extruded fin tubes: Offer a larger heat transfer area, but the base tube is mostly made of aluminum, resulting in a lower temperature resistance (≤260°C) than steel-based embedded fin tubes (≤400°C).
Aluminum embedded fin tubes: Steel tubes with steel fins have a temperature resistance of up to 400°C, while steel tubes with aluminum fins have a temperature resistance of 260°C; maximum pressure is 25 kgf/cm².
L-shaped wound fin tubes: Steel tubes with aluminum fins have a temperature resistance of only 180°C, while aluminum tubes with aluminum fins have a temperature resistance of 150°C.
Bimetallic rolled sheet tubes: Offer a temperature resistance of up to 260°C and offer superior corrosion resistance.
2. Structure
The unique feature of steel-aluminum embedded fin tubes lies in their embedded design.
The aluminum fins are embedded into the steel base tube through a special process, creating a tight bond between the two. This prevents the common problems of fins loosening or falling off the base tube, improving the overall stability and reliability of the fin tube.
This structure also increases the contact area between the fins and the base tube, improving heat transfer and fully utilizing the material’s performance.
Other fin tube types, such as sleeve-fin tubes, typically connect the fins to the base tube through machining or welding. This connection is relatively poor in tightness and stability, and over time, the fins may loosen or fall off, affecting heat transfer efficiency and service life.
Aluminum Embedded Fin Tubes: Aluminum fins are mechanically embedded into spiral grooves on the surface of the base tube (carbon steel/stainless steel) using a mechanical inlay process, achieving a contact pressure of 0.8-1.0 MPa, creating a tight fit.
L-Wound Tubes: L-shaped aluminum strips are wrapped around the base tube. This process is simple, but can easily loosen and results in higher contact thermal resistance.
Bimetallic Rolled Tubes: The fins are integrally formed with the base tube through a rolling process, providing superior corrosion resistance.
3. Applications
Steel-aluminum embedded finned tubes, due to their excellent overall performance, are widely used in various industrial heat exchange equipment, such as heat exchangers and coolers.
In particular, they offer unique advantages in applications requiring high heat transfer efficiency and structural strength, such as in the chemical, petroleum, and power industries.
Other types of finned tubes, however, are suited to specific applications or working conditions based on their unique characteristics. For example, copper finned tubes are commonly used in industries such as air conditioning and refrigeration due to their excellent thermal conductivity and processability. Aluminum alloy finned tubes have particular application value in applications with stringent weight requirements, such as the aerospace industry.