Why boiler use finned tubes?

In equipment that transforms thermal power, finned tubes are typically utilized to maximize the heat distribution surface. The heat transfer coefficient of water inside the tube is dozens or even hundreds of times greater than that of air outside the tube because the inside and outside of the tube are two different types of medium for convection heat transfer. In order to compensate for the air outside the tubes low heat transfer coefficient, fins are added outside the tube, considerably increasing its initial heat transfer area on the air side.

The following are the principal uses for finned tubes:

1. Fluids on either side of a heat transfer process have asymmetric heat transfer resistance. One side has a high heat resistance while the other has a low heat resistance. On the side with a high level of heat resistance, fins should be installed. For instance, a steam generator, air chiller, or boiler economizer.

2. To improve heat transmission, fins should be put on both sides of the tube at the same time if the heat transfer coefficient on both sides of the tube is very low. For instance, an air heater.

3. Finned pipes should not be used in place of threaded or corrugated pipes when the heat transfer coefficients on both sides of the pipe are high. Condenser at a power plant, for instance.

4. Finned tubes offer a distinctive environmental benefit and have a good anti-corrosion performance in use.

5. Another important quality of finned tubes is wear resistance. The wear resistance of finned tubes will always assist the machinery have a long life when assembling various pieces.

6. Finned tubes have the potential to reduce ash build up.

Finned tubes are categorized according to their construction and use.

Finned tube can be further divided into finned tubes that exchange heat with air, flue gas, organic medium, refrigeration medium, and finned tubes that are used to dissipate heat from electrical components.