Industrial Steam-heated Water Using Tube-fin Heat Exchangers

Industrial steam-heated water using tube-fin heat exchangers

Tube-fin heat exchangers consist of two main components: tubes and fins:

Tubes: Typically made of metal tubes (materials include copper, stainless steel, or carbon steel, selected based on the corrosiveness of steam and water), with high-temperature steam (heat source) flowing through the tubes. The steam condenses inside the tubes, releasing latent heat.

Fins: Metal sheets (fins, made of materials matching the tubes, such as copper fins or aluminum fins) are attached to the outer surface of the tube bundle (water side) using expansion joints. This increases the heat transfer area on the outer side of the tubes (water side).

Core advantages of finned tube heat exchangers in “steam heating water” applications

High heat transfer efficiency

The heat transfer coefficient of water (approximately 1000–5000 W/(m²・K)) is significantly lower than that of steam condensation (approximately 5000–15000 W/(m²・K)), representing a “heat transfer bottleneck” on the water side. Fins expand the heat transfer area on the water side (typically 5–10 times that of plain tubes), effectively compensating for the low heat transfer coefficient on the water side. This results in an overall heat transfer efficiency improvement of 30–50% compared to conventional plain tube heat exchangers.

Compact structure, space-saving

Under the same heat transfer capacity, the volume of a finned tube heat exchanger is only 1/3–1/2 that of a conventional shell-and-tube heat exchanger, making it suitable for industrial sites with limited space (such as small and medium-sized hot water stations or process heating lines).

Adapted to steam condensation characteristics

When steam condenses, it releases a large amount of latent heat (accounting for 70%-90% of the total heat). By circulating steam through the tubes, the high heat transfer coefficient advantage can be fully utilized; simultaneously, the steam flow resistance within the tube bundle is low, preventing gas accumulation, and enabling stable heat release.

Stable temperature control

The condensation temperature of steam remains constant (e.g., the condensation temperature of saturated steam at 0.3 MPa is approximately 133°C). By adjusting the steam flow rate (e.g., installing a regulating valve), the outlet water temperature can be precisely controlled (with an error typically ≤±2°C), meeting the stringent temperature requirements of industrial processes (e.g., cleaning, reactor heating, etc.).