Technology on Different Finned Tubes

It is fabricated with a batch of single fins that were processed by the punch press and then manually or mechanically, with a certain distance (wingspan) on the base tube.

HF (High Frequency)Solid Fin Tube

This is the earliest fin tube fabrication with low cost and simple production process/ technology, easy to maintain. Divides into manual set and mechanical set. Manual set uses a tool that relies on the power of man to press the fins one by one. This method is limited by the pressure of the fin, so it is easy to get loose. The machine - set fin is carried on the wing piece machine. Due to the mechanical impact or liquid pressure, the pressure of the fin is high, so it can be used in a larger volume. The bonding strength between fin and tube is high and not easy to loosen. Mechanical transmission has high productivity, but the noise is large, the safety is poor, and the working conditions of the workers are not good. Although the hydraulic transmission does not have the above problem, but the equipment price is more expensive, the technical requirement to use maintenance personnel is higher, its productivity is also lower.

Currently HF Fin Tube is one of the most widely used helical fin tubes, you can see it as waste heat recovery in power, metallurgy, concrete, oil and gas, petrochemical, etc. When winding the steel strip around steel tube, the use of high frequency current skin effect and proximity effect on steel strip and steel pipe surface heating, until the plastic state or melt, the coil steel belt must be under pressure to complete welding. Comparing with embedded type and spot welding spiral crimped type, it is more advanced either on fin tube quality or production efficiency or automation degree.

Three-Roll Extruded Integral Fin Tube

The Extruded Fin is formed from an outer aluminum tube with a large wall thickness (muff), which is aligned over an inner base tube. The two tubes are pushed through three arbors with rotating discs that literally squeeze or extrude the aluminum fins up and out of the muff material in a spiral shape in one operation. Comparing with welding fin tube, DR Extruded Fin has higher production efficiency with low cost on material and high heat transfer. At present, it divides into copper or aluminum single metal fin tube and bi-metal composited fin tube.

Fin tube manufacturers produce a wide range of fin tubes. They are used in heat exchangers (air, water and chemically cooled) for various industries such as petroleum, petrochemical, steel, power generation and many more.

Corrosion protection processes are performed during fin tube manufacturing and the material used is corrosion resistant. Some fin tube types are:

Type

Fin Tube Properties

“L” fin tubes

• Max working temperature – 150 °C (302 °F)
• Atmospheric corrosion resistance – acceptable
• Mechanical resistance – poor
• Fin material – aluminum, copper

"LL" fin tubes

• Max working temperature – 180 °C (356 °F)
• Atmospheric corrosion resistance – acceptable
• Mechanical resistance – poor
• Fin material – aluminum, copper

"KL" fin tubes

• Max working temperature – 260 °C (500 °F)
• Atmospheric corrosion resistance – acceptable
• Mechanical resistance – acceptable
• Fin material – aluminum, copper

"KL" fin tubes

• Max working temperature – 260 °C (500 °F)
• Atmospheric corrosion resistance – acceptable
• Mechanical resistance – acceptable
• Fin material – aluminum, copper

"G" fin tubes

• Max working temperature – 400 °C (752 °F)
• Atmospheric corrosion resistance – poor
• Mechanical resistance – acceptable
• Fin material – aluminum, copper, carbon steel

Extruded fin tubes

• Max working temperature – 285 °C (545 °F)
• Atmospheric corrosion resistance – excellent
• Mechanical resistance – excellent
• Fin material – aluminum