Extruded Fin Tube, Extruded Finned Tube,

What is extruded aluminum fin tube?

Extruded aluminum fin tube is formed as bi-metallic tubes. Extruded aluminum fin tube include a base tube and an aluminum muff tube. The fins are formed on a cold rolling process from the wall thickness of the aluminum muff tube. Extruded fin gives very good corrosion protection to the base tube, as the base tube is not visible to the atmosphere in between the fins.

How to fabricate the extruded aluminum fin tube?

The extruded fin is made of an outer aluminum tube with a thick wall (muff) that is aligned over an inner base tube. The two tubes are pushed through three arbors with rotating discs that squeeze or extrude the aluminum fins up and out of the muff material in a spiral shape in a single operation. As a result, the tubes base is completely connected to the main tube. Since these fins never break, deform or loosen, their heating efficiency does not change over time.

Insert tube into the aluminum muff tube–>compressing or rolling–>strip peeling–>washing–pressure test–>blast blowing–>packaging.

Extruded aluminum fin tube size and material:

Extruded aluminum fin tube advantages:

1. 100% fin-to-tube bond providing exceptional efficiency and longevity.
2. Excellent corrosion protection on the base tube.
3. Easy to clean with a high-pressure water jet without deforming the fins.
4. As the outer sleeve is continuous No galvanic corrosion between the tube and fins.
5. The bonding of the outer and inner tubes removes the risk of loss of contact with the aluminium due to thermal stress and fins are vibration resistant.
6. Higher heat transfer performance for the life of the unit.
7. Extruded Finned tubes are commonly used in applications with temperature up to 325 °c.

The extruded finned tubes are produced by compressing an aluminum tube or sleeve, onto the base tube. The bloom is exposed to very high pressures which essentially “grows” the fins into the final fin profiles. This process manufactures an excellent strong joint with great resistance (fin stiffness) as well as exceptional heat transfer capabilities (longevity, temperature range). The advantage of extruded fin tubes are full protection of bare tube against corrosion and fin has high mechanical strength. Extruded finned tubes provide the most stable performance over time as compared to the other fin types. The fin is rolled from an outer aluminum tube by a process using pressure to create a rolled “pressure bond” between the liner tube and fins. The aluminum fin material completely encloses the tube, except at the ends where a tube coating can be applied.

Extruded aluminum fin tube application:

Primarily extruded finned tubes are used in high temperature conditions and corrosive atmospheric conditions, such as operating temperatures less than 300°C or off-shore applications; heat pipes air to air heat exchangers for HVAC applications, air dehumidification in air treatment plants, energy recovery in air exhaust system. This kind of fin design is the least economical as compared to the other fin types; main reason due to the increased amount of aluminum used around 40% also increased labors during the manufacturing. However this increased cost can be compensated if using lower grade parent tube material. Extruded aluminum fin tube widely used in Air Cooler,Air preheater,Charge Air Chiller, Condenser,Evaporator, Fluid Cooler, Gas Cooler,Oil Cooler, Radiator, Refrigeration,Steam to Air Heat Exchanger etc.