L Finned Tube(LL/KL Finned Tube)
Acree offers a range of wrapped finned tubes, including L-footed, double overlap (LL) fins, and knurled (KL) finned tubes.
- High efficient
- Cost effective
- Maximum heat transfer at lower temperatures.
- The unique L-shaped design holds fins rigidly to withstand heat cycling and high velocity air vibration.
- Introduction
- Materials and Properties
L Finned Tube
The L finned tube features fins shaped in an L form, which are tension-wound onto the outer surface of the base tube. The “L” foot of the fin provides enhanced corrosion protection for the base tube.
LL Finned Tube
Similar to the L-shaped finned tube, the LL finned tube has overlapping fin feet that fully cover the outer surface of the base tube. This design offers superior corrosion protection compared to the standard L-type.
KL Finned Tube
The KL finned tube is manufactured similarly to the L-type but with an additional step: the base tube’s surface is knurled before the fins are applied. The fin foot is then pressed into the knurled surface, creating a stronger bond between the fins and the tube, which significantly enhances heat transfer efficiency.
| Fins Per Inch | 100~433 FPM |
|---|---|
| Fin Height | 10 to 16mm |
| Fin Material | Cu, Al1100,Al1060 |
| Tube OD | 15.88 to 32mm |
| Tube Material | Cu, CuNi, Br, Al, SS, CS, Ni, Ti |
| Max Process Temperature, Single L
Max Process Temperature, Double Overlap L |
180°C
260°C |
| Max Process Temperature, Knurled L-Foot | 400°C |
Normal base material: Carbon Steel/ Carbon Alloy Steel/Stainless Steel/ Nickel Alloys/ Copper/Copper Alloys/Titanium, A179, A192, A210, stainless tube A269/A213 T5 T11 T22 304 316/316L and so on.
Manufacturing Process
Production Process of L-Foot Fin Tubes
- Preparation: The process begins with selecting a base tube, typically made from materials like copper, stainless steel, or carbon steel. The tube is cut to the required length and prepared for the finning process.
- Finning: L-shaped fin strips are independently formed and then securely wrapped around the base tube. These fins are often made from high-conductivity materials like aluminum or copper to optimize heat transfer efficiency.
- Bonding: The fin strips are firmly attached to the base tube using methods such as mechanical bonding, soldering, or brazing. This step ensures a strong, durable connection between the fins and the tube for long-lasting performance.
What is the advantages and weak points of the L footed finned tube?
Advantages of L-Foot Finned Tube:
- Ideal for Low-Temperature Applications: Suitable for use in environments with lower temperatures.
- Cost-Effective Solution: Among the various finned tube types, L-foot is the most economical option.
- Reusability: Damaged fins can be easily removed during production, allowing the base tubes to be reused for re-finning.
- No Helical Grooving Required: There’s no need to create a helical groove on the core tube, simplifying the production process.
- Compatible with Thin-Walled Tubes: L-foot fins can be applied to super thin-walled tubes, making them particularly advantageous when using costly alloys as core materials.
- Heat and Corrosion Resistance: Capable of withstanding temperatures up to 130°C without risk of atmospheric corrosion or thermal stress.
Weak points of L-Foot Finned Tube:
- Vulnerability to Mechanical Damage: The fins are not robust enough to resist damage from external forces applied to the finned area.
- Careful Handling Required: Must be handled with extra care to prevent fin damage during transportation and installation.
- Limited Cleaning Methods: Can be susceptible to damage if cleaned with steam or high-pressure water.
- Exposed Areas: Due to the helical wrapping, sections of the base tube remain uncovered, potentially exposing it to corrosive elements and galvanic corrosion at the base of the fins.
- Strict Base Tube Requirements: The base tubes must be perfectly straight and have a smooth exterior to ensure proper finning.
- Fins Must Be Secured: The fins should be fixed at both ends to prevent unwrapping during operation.
Related Products
L-foot finned tubes are widely used in industries where heat exchange is critical due to their enhanced surface area for heat transfer.
Oil and Gas Refineries
Petroleum, Chemical, and Petrochemical Industries
Natural Gas Treatment
Power Plants
Air Conditioning
Compressor Coolers
Advantages of KL Fin Tubing / Knurled Finned Tubes:
- Provides corrosion protection for the tube
- Suitable for medium temperature applications
- Stronger bond between the fin and tube
- Better thermal contact compared to standard L-fin tubes
- Enhanced heat transfer performance due to the knurling
- Improved atmospheric corrosion resistance of the core tube
- Excellent stability
- Resistant to vibrations
- Can be used at temperatures up to 400°C
- A unique combination of high thermal performance, stress resistance, and atmospheric corrosion protection
KL finned tubes are an excellent alternative to other types of finned tubes. The manufacturing process is similar to that of L-fin tubes, with the base tubes being knurled before the fin feet are applied. After application, the fin foot is knurled into the corresponding grooves on the base tube, resulting in a stronger bond and enhanced heat transfer characteristics.
To provide you with a prompt and accurate offer, we would be grateful if you could send us a detailed inquiry including the following information:
- Base tube material
- Base tube size (OD x WT x Length)
- Fin material
- Fin type
- Fin diameter or height
- Fin thickness
- Fins per inch, meter, or fin pitch
- Length of plain, unfinned ends
- Quantity of finned tubes