Before continuous winding on the surface of steel tube, the outer surface of base tube should be rolled out. After winding, the fin foot is knurled into corresponding knurling on the base tube therefore enhancing the bond between fin and tube.

Comparing with L type fin and LL type fin, it has better heat transfer same as L foot fin, extruded fin, KL Fin Tube and Embedded G Fin, double L footed fin are primarily used in air-cooled applications such as large radiators, compressor oil coolers, and other forced-draft or induced-draft air-cooled applications.

Embedded G Fin Tube, L Foot Fin, LL Fin, KL Fin Tube and Extruded Fin Tubes are widely applied tube bundle elements for air coolers and the general application fields are:

Chemical and petrochemical industry

Steam condensate systems

Heat exchangers for power plants (such as geothermal power plants, nuclear plants, electric plants, etc)

Food processing plants and refrigeration technology.

Tube Material:

Seamless Carbon Steel. (such as SA179, SA192, SA106, SA213 T11, SA213 T5.)

Stainless Steel (SA213 TP304, SA213 TP316, Alloy 825, ASTM B163 N04400)

Copper (UNS C12200, C14200, C70600, CuNi 70/30, CuNi 90/10)

Titanium: (AB38 Gr.2)

Fin Material: Aluminum (Al1050, Al1060, Al1100) and Copper

Increase fin to tube bond

Better thermal contact and heat transfer efficiency then L Foot Fin

Increased atmospheric corrosion protection of the core tube

Resistant to vibrations

Good stability

Dimension of KL Fin Tube for references as below

Base Tube Diameter: 12.7mm to 50.8mm

Base Tube Wall thickness: 1.65mm Min depending on tube material and outside diameter

Knurled Fin Height: 7mm to 25.4mm, usually standard height is 15.875mm.

Knurled Fin Strip Thickness: 0.4mm

Fin Pitch: 8-12FPI.