The application of finned tube heat exchangers in refrigeration systems

Finned tube heat exchangers play a core role in air conditioning and refrigeration systems. Their process optimization and practical application cases directly affect the energy efficiency, reliability and cost of the system. The following is a detailed analysis of its specific processes and typical cases:

1. Key Manufacturing Processes of Finned Tube Heat Exchangers

1.1. Material selection

1.1.1.Copper tubes + aluminum fins: The combination of copper tubes (with high thermal conductivity) and aluminum fins (lightweight and corrosion-resistant) is commonly used in air conditioning systems, such as the Φ4mm to Φ30mm copper tubes displayed by Shandong becihen mechanical and electrical equipment Co.,ltd.

1.1.2. All-aluminum microchannel heat exchanger: Some manufacturers adopt an all-aluminum structure, such as the aluminum flat tubes of Shandong beichen M&E Co.,Ltd., which have the advantages of lightweight and low charge volume, but the corrosion problem needs to be solved.

1.1.3. 5052 series aluminum alloy: Shandong beichen uses this material as the support string plate to enhance low-temperature corrosion resistance and thermal conductivity.

2. Fin processing technology

2.1. Stamping forming: The high-efficiency fin stamping die displayed by Shandong beichen M&E Co., Ltd. can be customized with different fin shape sizes.

2.2.Corrugated fins/window-opening fins: Enhance air side turbulence and increase heat transfer coefficient, but the risk of ash accumulation needs to be balanced.

2.3.Hydrophilic/hydrophobic coating: Used to prevent frosting or accelerate drainage. For instance, the defrosting, water guiding and splash-proof device of Shandong Beichen M&E uses brush strips to reduce ice formation.

3. Tube-wing combination technology

3.1. Mechanical tube expansion: Traditionally, copper tubes and fins are fixed through mechanical expansion joints, but gaps may occur due to thermal expansion and contraction.

3.2.High-frequency welding: Enhances bonding strength and reduces contact thermal resistance. For instance, some manufacturers use welded finned tubes.

3.3. Brazing (microchannel heat exchanger) : Aluminum flat tubes and fins are connected by brazing, but the problems of pitting and fin detachment need to be addressed.

4. Optimization of pipeline layout

4.1. Small pipe diameter technology: For instance, in the R290 refrigerant system, 5mm copper tubes are used instead of 7mm ones, increasing the heat exchange capacity by 34.19% and reducing the consumption of copper and aluminum by 28.6%/30%. 10.

4.2.Multi-tube cross-arrangement: For instance, a certain patented technology uses two tubes with reverse fin penetration to increase the pipe length and enhance the heat exchange area by 7.

4.3.U-shaped tube + header design: Shandong beechen M&E's patented technology reduces capillary resistance and improves energy efficiency through headers.

5. Analysis of Typical Application Cases

5.1.Household air conditioner (evaporator/condenser)

5.1.1.Case: TCL air conditioners adopted reinforced brackets to fix the main outlet pipe, solving the problem of cracking and leakage caused by traditional welding.

5.1.2.Optimization points: The diameter of the copper tube has been reduced from 7mm to 5mm, and the refrigerant charge has been decreased, making it suitable for R290 environmentally friendly refrigerant 10.

5.2. Commercial central air conditioning

5.2.1.Case: The finned heat exchanger of Guangdong Ouke adopts the header and flow diversion technology. During cooling, the liquid refrigerant directly enters the header, reducing the capillary resistance and significantly improving energy efficiency.

5.2.2.Optimization point: The floating coil design is adopted to prevent pipe string damage and increase service life by 6.

5.3. Cold chain cold storage (evaporator)

5.3.1.Case: The defrosting, water guiding and anti-splash device of Yantai Aowei uses brush strips to reduce the freezing of splashing water droplets and lower the defrosting energy consumption by 4%.

5.3.2.Optimization point: It adopts a 5052 aluminum alloy support structure to enhance low-temperature corrosion resistance.

5.4. Automotive air conditioning (microchannel heat exchanger)

5.4.1. Case: The aluminum flat tube microchannel heat exchanger of Wanhe Trading has inner ribs to enhance disturbance and increase the heat transfer coefficient, but the corrosion problem needs to be solved. 2.

5.4.2.Optimization point: The vertical fin structure of Jiangsu Keling Storage reduces water retention and improves drainage efficiency. 2.

5.5.Industrial refrigeration (Shell and Tube Heat Exchanger)

5.5.1.Case: Hangzhou Shen's CO₂ spiral tube heat exchanger, with strong pressure resistance, is suitable for carbon dioxide heat pump systems 2.

5.5.2.Optimization point: Spiral baffles are adopted to enhance turbulence and improve heat exchange efficiency. 2

6. Future Development Trends

6.1. Smaller pipe diameters: Copper pipes with diameters of 5mm and smaller are becoming a trend, reducing material costs and refrigerant charges by 10%.

6.2. Intelligent control: Combined with PLC to optimize the defrosting cycle, such as automatically adjusting the electric heating defrosting strategy. 4

6.3. Corrosion resistance optimization: Develop new coating or alloy materials, such as pre-coated aluminum fins (SiO₂ type) 2.

6.4. Microchannel technology: Vertical finned and all-aluminum microchannel heat exchangers are gradually replacing traditional finned tubes.

7. Conclusion

The process optimization of finned tube heat exchangers (such as small tube diameters, cross-arrangement, and new coatings) and case applications (such as air conditioners, cold storage, and automotive air conditioners) have demonstrated their high efficiency and adaptability in refrigeration systems. In the future, with the advancement of materials science and manufacturing technology, its energy efficiency and reliability will be further enhanced.

Shandong Beichen Electromechanical Equipment Co., Ltd. constantly innovates and improves its technology in response to market demands and industry changes. It has independently developed some finned tube heat exchangers that meet market needs, which have received extensive attention and high praise from the market.

Related Links:

How to understand finned tube heat exchangers?

Fin Tube Heat Exchanger Manufacturing Process