Industrial SA210 Boiler Spiral Fin Tube With U Bends For Heat Recovery

Spiral finned tubes are widely used in heat recovery of boiler economizer, air preheater, and waste heat boiler, as well as heat exchange equipment in chemical industry, pressure vessel and other fields. The capacity of units used in boilers has also increased from small to large, and their applications are increasing day by day. At present, many professional manufacturers in China can produce high frequency resistance welding, brazing spiral finned tubes, and the production equipment and technology of finned tubes have been developed, designed and manufactured from importation, digestion and absorption to self-development. The quality has reached the requirements of advanced foreign standards.

Advantages of using finned tubes:

1. the heat transfer area is increased in the effective space to improve the heat transfer effect.

2. Reduce the occupancy space of heat transfer surface and reduce its volume, especially for fast-loading boilers.

3. Reduce the equipment cost and improve the safety of equipment.

4. Due to the decrease of water side pressure drop, the operation cost is reduced.

5. The stiffness of finned tubes are increased, and the seismic resistance of the tube is improved.

Manufacturing method

Spiral finned tubes can be manufactured by various ways. At present, there are several main manufacturing methods for finned tubes used in heat exchangers such as boilers and pressure vessels.

High frequency resistance welding spiral finned tube

High frequency resistance welding spiral finned tube is kind of high frequency current imported into the welded parts. By using the resistance heat generated by the current through the contact surface of the welded joints and adjacent areas, the welded contact surface can reach the plastic state of melting or semi-melting, then appropriate pressure is applied to the welded contact surface, to complete welding work of finned tubes.

Brazed spiral finned tube

Brazing spiral finned tube is a kind of metal filler with a melting point lower than that of the welded part, and then heating the brazing temperature. When the welded part is not melting, the solder melting well wets and brazes, and forms the brazing joint depending on expansion and dispersion of the contact point of the welded part, thus completing the welding of the spiral finned tube.

Integral spiral finned tube

Integral spiral finned tube is formed by extrusion and tie of thick-walled tube(billet tube) under the condition of medium frequency continuous heating.It is known as the latest method of manufacturing finned tube in domestic market. It is developed by a domestic company and the researched and developed integral finned tube as well as the self-manufactured integral finned tube manufacturine equipment have been applied for patents.