L KL LL Type Fin Tube

Wound L KL LL Type Spiral Fin Tube.This type of Fin Tube widely finds acceptance where the Heat Transfer Temperature is relatively lower and the cost needs to be controlled. These type of Fin Tubes are relatively lesser in cost as compared to the ‘G’ Type Fin Tube and the Extruded Type Fin Tube.

The finned tube is made by attaching fins to the outer surface of a base tube, which increases the surface area of the tube and enhances its heat transfer performance.

The L/LL/KL configuration refers to the shape of the fins on the tube. L-shaped fins have a flat top and a tapered bottom, while LL-shaped fins have a double tapered structure with a groove in the center to improve the bonding strength between the fins and the base tube. KL-shaped fins are similar to L-shaped fins but have a knurled surface to increase the contact area between the fins and the base tube.

L/LL/KL finned tubes are commonly used in air-cooled heat exchangers, such as radiators, condensers, and evaporators, as well as in industrial process heating and cooling applications.

L finned tubes, LL (Doulbe L) finned tubes, KL finned tubes (knurled fin tubes) (with aluminum fins)The aluminum fin strip or the copper fin strip is folded into an L shape and spirally wound tightly under the action of tension on the outer surface of the base tube. Tension in the fin strip is wrapped around the tube serves to make the fin foot forcefully on the tube, thus hold the fin firmly in place.

‘L’ Type Fin Tube
In the ‘L’ type fin tube, also referred to as the ‘L’ foot fin tube, the fin is constructed by spirally wrapping the fin stock around the base tube, hence its alternative name, spirally wound fin tube. The base of the fin tube is molded into an ‘L’ shape. This design not only provides a sturdy foundation for the fin but also offers some protection against atmospheric corrosion.

‘LL’ フィンチューブ
The ‘LL’ fin tube is an advancement of the wrap around fin tube and the ‘L’ fin tube. It follows a similar manufacturing process to the ‘L’ type, with the key enhancement being the complete overlap of the ‘L’ foot of one fin by the ‘L’ foot of the subsequent fin. This overlapping creates a dual ‘L’ foot shape at the base, enhancing the tube’s corrosion resistance.

‘KLM’ or Knurled ‘L’ Foot Fin Tube
The ‘KLM’ fin tube, also known as the knurled ‘L’ foot fin tube, represents the most common and widely preferred type of wrap around fin tube currently in use. Manufactured similarly to the ‘L’ fin tube, the distinguishing feature involves knurling the tube and the ‘L’ base of the fin stock simultaneously. This process results in a more secure bond and improved thermal contact between the fin and the tube.