What are the classifications of finned tubes according to manufacturing process and material?

What are the classifications of finned tubes according to manufacturing process and material?

According to the manufacturing process, finned tubes can be classified as integral finned tubes, welded finned tubes, high frequency welded finned tubes and mechanically connected finned tubes.

(1) Integral finned tubes, made by casting, machining or rolling, with the fins and tubes as a whole.

(2) Welded finned tubes, manufactured using processes such as brazing or inert gas shielded welding. Modern welding technology allows fins of different materials to be joined together and enables finned tubes to be manufactured simply and economically, with good heat transfer and mechanical properties, and has been widely used. As the residue in the weld seam is not conducive to heat transfer and can even cause fracture, the quality of the welding process must be ensured when producing these finned tubes.

(3) High-frequency welding finned tubes, using high-frequency electrical induction generated by a high-frequency generator, so that the surface of the tube and the fins in contact with the high temperature, in the depth of about 10μm to dissolve the two, and then pressure to make the fins and tubes together. No flux or solder, simple manufacture, high productivity, excellent heat transfer and mechanical properties. This is the most ideal type of finned tube, which is being recognized and adopted by the majority of users.

(4) Mechanically connected finned tubes, there are usually three types of finned tubes, such as winding type, inlay type, sleeve type or string type. The finned tube is simple to manufacture, the metal belt is mechanically or welded around one end of the tube, and the torque of the tube rotation will wind the metal belt tightly around the outer wall of the tube, and the other end is fixed into the finned tube. The material used for the winding can be copper, steel or aluminium strip.

Commonly used finned tube heat exchangers are finned tubes, mainly wound, tied, strung and high frequency welded finned tubes. The finned material is usually steel tube with steel fins, steel tube with aluminium fins, stainless steel tube with stainless steel fins, copper tube with copper fins and copper tube with aluminium fins. The material of the tie fin type is steel tube with fins, stainless steel tube with aluminium fins, copper tube with aluminium fins. String fins are available for copper tubes with aluminium fins and stainless steel tubes with stainless steel fins. The high frequency welded ones are steel tube high frequency welded steel fins, stainless steel high frequency welded stainless steel fins.