Low-fin tubes are enhanced heat transfer elements made by rolling continuous spiral fins on the outer surface of steel pipes. Their core function is to improve heat exchange efficiency by increasing the outer surface area of the pipes. Compared with traditional plain tubes, the outer surface area of low-fin tubes can be more than 3.5 times the inner surface area, significantly enhancing heat transfer performance. They are key components for achieving miniaturization, lightweight design, energy conservation, and consumption reduction in heat exchange equipment.

I. Structural and Performance Advantages

Low-fin tubes are processed using a mechanical rolling process, forming an integrated structure between the base tube and the fins. This fundamentally avoids problems such as fin detachment or contact thermal resistance. The key structural parameters include fin height, pitch (distance between adjacent fins), fin thickness, and finning ratio (the ratio of the total outer surface area of the finned tube to the area of the original plain tube). Generally, the larger the finning ratio of a low-fin tube, the more obvious the expansion of the effective heat exchange area, making it suitable for scenarios with strict requirements for heat transfer efficiency.

II. Production Technology and Reliability

The mainstream production process is the three-roll rolling method: Under the coordinated action of the rolls and the mandrel, regular spiral fins gradually form on the outer surface of the steel pipe. The entire processing process is divided into three stages: biting-in, rolling, and shaping, ensuring that the fins have a complete shape and a smooth surface. This process guarantees a tight connection between the fins and the base tube, enabling the product to have both deformation resistance and vibration resistance characteristics. Even after bending, the fins can remain stable.

III. Specification and Material Selection

Low-fin tubes come in a variety of specifications. The diameter usually ranges from φ16mm to φ32mm, and the length can be customized up to 9000mm. Between 19 and 26 fins can be processed per inch (25.4mm) of the tube body, allowing users to choose according to their actual needs. In terms of materials, common options include:

– Stainless steel (304/316): It has excellent corrosion resistance and is suitable for the chemical industry and marine environments.

– Carbon steel (10#, 20#): It offers high cost-effectiveness and is commonly used in general industrial fields.

– Duplex steel (2205): It combines strength and corrosion resistance and is suitable for high-temperature and high-pressure scenarios.

– Titanium alloy: It is resistant to acid and alkali corrosion and is suitable for extreme working conditions.

IV. Application Examples in Multiple Scenarios

1. HVAC systems: As the core components of condensers and evaporators, low-fin tubes reduce the equipment volume and energy consumption through enhanced heat exchange.

2. Power and energy industry: They recover waste heat in power plant boilers and low-temperature economizers, effectively utilizing the flue gas temperature from 120 to 180°C and improving energy efficiency.

3. Petrochemical industry: They are used in the heat exchange section of refining equipment, and the corrosion-resistant materials can handle complex medium environments.

4. New energy vehicles: They regulate the temperature in the battery thermal management system to ensure battery performance and lifespan.

5. Food and pharmaceutical industries: Small-diameter models meet the requirements of clean production through precise temperature control and support easy-to-clean designs.

V. Maintenance and Selection Recommendations

The maintenance of low-fin tubes mainly involves regularly cleaning the ash on the fins and checking the sealing of the connections. Their compact design facilitates installation and cleaning. When selecting low-fin tubes, users need to comprehensively consider the following factors:

– Medium characteristics (temperature, corrosiveness, flow rate);

– Space limitations and weight requirements;

– Budget and long-term operating costs.

With the advantages of high-efficiency heat transfer, stable structure, and flexible adaptation, low-fin tubes have become an indispensable solution in the heat exchange field, continuously promoting the energy-saving upgrade and performance optimization of industrial equipment.