How to Choose the Right High Frequency Welded Finned Tube?

Selecting the right high frequency welded finned tube requires a comprehensive consideration of material, structural parameters, process performance, and suitability for the operating conditions. The following are key decision-making factors:

What is a high frequency welded finned tube?

High frequency welded finned tubes are a highly efficient heat exchange component made by welding steel strips and tubes together using high frequency current technology. They are widely used in industrial heat exchange applications.

High-Frequency Welded Finned Tube Structural Design

Base Tube Specifications: Diameter range DN15-DN150, wall thickness 2.0-5.0mm. Thicker wall tubes are required for high-pressure applications.

Fin Parameters:
Height 8-25mm (High fins are suitable for clean environments, low fins are suitable for dusty environments)

Thickness 0.3-1.2mm (Thick fins for high temperatures, thin fins for low temperatures)

Pitch 3-10mm (Smaller pitch increases heat transfer area, larger pitch prevents dust accumulation)

Shape: Spiral (accounting for over 80% of industrial applications) and annular; the former is suitable for variable airflow scenarios.

I. High-Frequency Welded Finned Tube Material Selection

Base Tube Material

Carbon Steel (Q235B/20# Steel): Low cost (1/3-1/2 that of stainless steel), with a thermal conductivity of approximately 45W/(m・K). Suitable for medium to low temperatures (≤400°C) and non-corrosive environments (such as residential heating), but requires regular anti-corrosion maintenance.

Acciaio inossidabile (304/316L): Highly corrosion-resistant. 316L can withstand chlorine-containing media and is suitable for high temperatures (≤600°C) and corrosive environments. Flue gas (such as chemical and waste incineration), but the cost is high and the thermal conductivity is low (16-18 W/(m・K)).

Copper/Aluminum: Copper finned tubes have high heat transfer efficiency (heat transfer coefficient 110 W/(m・K)), but are expensive. Aluminum finned tubes are 30% cheaper and suitable for drying flue gas.

Fin Material

Must match the base tube: Carbon steel base tubes with aluminum fins can reduce costs, while stainless steel base tubes with copper fins can extend the life of chlorine-containing media.

II. High Frequency Welded Finned Tube Structural Parameter Design

Base Tube Specifications
Diameter DN15-DN150, commonly DN25-DN80; Wall Thickness 2-6mm; High-pressure applications (≥2.5 MPa) require thick-walled tubes ≥3.5mm.

Fin Parameters
Height: 8-25mm. Tall fins (15-25mm) increase heat transfer area, but >25mm require ribs to prevent vibration.

Thickness: 0.3-1.2mm. Thick fins (0.8-1.2mm) are recommended for high temperatures (>200°C).

Pitch: 3-10mm. For clean environments, choose a smaller pitch (3-5mm); for dusty environments, choose a larger pitch (8-10mm) to prevent clogging.

Shape: Spiral (80% of the time) for variable airflow, circular for stable airflow.

III. High Frequency Welded Finned Tube Process Performance Requirements

Welding Quality
Weld seam strength must reach over 90% of the base tube, thermal resistance ≤ 0.0005 m²/K/W, and detachment rate < 0.1%.

Production Control
Welding speed 10-30 m/min, uniformity error ≤ 5% per meter, straightness deviation ≤ 1 mm/meter.

IV. High-Frequency Welded Finned Tube Operating Conditions

Temperature and Pressure
Carbon steel is suitable for temperatures between -30°C and 350°C, and ≤ 2.5 MPa; stainless steel is suitable for temperatures between -196°C and 600°C, and ≤ 4.0 MPa.

Fluid Characteristics
Low-density fins (8-15 mm pitch) are recommended for dusty gases, while high-density fins (3-5 mm pitch) are recommended for clean gases.

Maintenance Requirements
Stainless steel is preferred for corrosive environments. Carbon steel with galvanizing is recommended for stable operating conditions and limited budgets.

V. High-Frequency Welded Finned Tube Typical Tube Application Scenarios

Industrial Heating: Steam-type carbon steel finned tubes (DN50-DN80), covering 200-500 square meters per unit

Chemical/Power Industry: 316L stainless steel finned tubes (DN100-DN150), resistant to high-temperature corrosion

Air Conditioning and Refrigeration: Copper-aluminum composite finned tubes, improving COP by 8%-12%

What is a high-frequency fin tube welding machine?

The spiral fin tube high frequency welding production line is a fin tube welding machine developed independently based on the welding needs of stainless steel and alloy steel fin tubes and our experience and theoretical knowledge in fin tube welding technology. The so-called single-circuit system replaces the original two-circuit (or three-circuit) inductively coupled high-frequency fin tube induction heating equipment with a single-circuit, capacitively coupled high-frequency fin tube induction heating system. Product specifications include 100KW, 200KW, and 300KW. In addition, significant technical improvements have been made to the fin tube winding, forming, and welding processes. Currently, our company is the only company in my country that manufactures this single-circuit, improved high-frequency fin tube welding system with winding and forming functions.

This equipment has been used and proven for many years, with stable performance and advanced technology, earning it the trust and praise of all users.