Inspiration for Spiral Finned Tubes in Economizers

The utilization of spiral finned tubes in economizers brings about several advantages, contributing to enhanced energy efficiency and performance. Here are key insights and considerations:

1. Extended Heating Surface for Improved Performance:

   - Extended economizer heating surface reduces ash surface abrasion and enables a compact structure.

   - It contributes to reduced air flow resistance, flow resistance of the working fluid, and overall metal consumption.

2. Spiral Tube Utilizing High-Frequency Welding:

   - Spiral finned tubes are formed using high-frequency welding, where a strip is spirally welded along the optical tube track.

   - The welding process allows fins and the base pipe to melt into one, minimizing contact resistance and withstanding alternating heat stress.

3. Structural Parameters of Spiral Fin Economizer:

   - Key parameters include base tube diameter, spiral fin tube wall thickness, fin thickness, height, pitch, and arrangement (inline or staggered).

   - Adaptations may be required based on economizer installation height and space limitations.

4. Heat Transfer Coefficient and Energy Efficiency:

   - Extended heating surfaces exhibit increased heat transfer and energy efficiency compared to light pipes.

   - Spiral finned tubes, despite having a smaller heat transfer coefficient, demonstrate the largest energy efficiency due to their expansion coefficient.

5. Impact of Base Pipe Diameter on Heat Transfer:

   - The increase in the diameter of the base pipe leads to a reduction in various heating surface heat transfer coefficients and energy efficiency.

   - Proper consideration of base pipe diameter is crucial for maintaining energy efficiency.

6. Wear Resistance Improvement:

   - Spiral fin-type and helical fin-type expansion economizer heating surfaces demonstrate improved wear resistance.

   - This improvement is attributed to changes in the flow field of flue gas and alterations in flue gas flow rate.

7. Selection of Small Group for Enhanced Efficiency:

   - Choosing a smaller group for the economizer heating surface enhances heat transfer tube diameter energy efficiency and reduces wear.

   - Larger base pipe diameters offer advantages such as increased wall thickness and improved wear resistance.

8. Extended Surface Technology for Convection Heating Surfaces:

   - Extended surface technology is recommended for convection heating surfaces, especially when gas side heat transfer coefficients are significantly smaller than water or steam side coefficients.

9. High-Frequency Resistance Welding Advantages:

   - High-frequency resistance welding in spiral finned tubes offers distinctive features, including solid welding, minimal contact resistance, and strengthened base tube strength.

   - This method allows for a substantial reduction in the number of tubes, saving material and reducing the chance of exploding or leaking.

10. Increased Heating Surface Layout and Temperature Reduction:

   - Spiral finned tubes enable a greater heating surface layout per unit volume, allowing for lower flue gas velocities and reduced wear.

   - Arranging more fins and tube heat transfer area in the same space can further reduce flue gas temperature, addressing challenges related to high flue gas temperatures.

In conclusion, the use of spiral finned tubes in economizers presents a comprehensive solution for optimizing heat transfer, energy efficiency, and wear resistance, contributing to the overall performance and longevity of boiler systems.

Extended surface economizer