KL Fin Tube (KL Type Knurled L-Footed Finned Tube for Heat Exchangers)

Material / Product Description

KL fin tube (KL type knurled L-footed finned tube) is a wrap-around finned tube where an L-shaped fin strip is helically wound onto a pre-knurled base tube. The knurling and L-foot create a tight mechanical interlock and a large metal-to-metal contact area, improving heat transfer efficiency and fin bond stability compared with standard L or LL fins.

Typical base tube materials include seamless carbon steel (ASTM A179, A192, A210 Grade A1), low-alloy steel (ASTM A213 T11) and stainless steel (ASTM A213 TP304). KL fin tubes are mainly used in air-cooled heat exchangers, gas coolers and compact finned bundles in power, petrochemical and gas-processing plants.

Specifications

Base tube

• Outside diameter: approx. 12.7–50.8 mm (½"–2")

• Wall thickness: typically ≥1.65 mm, per design pressure and code

• Materials (examples): ASTM A179, A192, A210 Gr A1, A213 T11, A213 TP304

Fin geometry

• Fin height: about 8–20 mm

• Fin thickness: about 0.3–0.8 mm

• Fin pitch: about 8–12 fins per inch

• Fin materials: aluminium or copper

Temperature range

• Usual design upper limit in air-cooler service: around 250 °C, subject to tube alloy, fin material and design code.

Key Features

• Strong fin-to-tube bond with knurled base tube and L-foot fin

• High heat-transfer efficiency due to large metal contact area

• Good resistance to thermal cycling and vibration

• Flexible combinations of tube and fin materials to match the process

Our Advantages

1. Thermal cycling and fin loosening
   KL fin tubes keep the fin mechanically locked into the knurled tube surface, maintaining performance after repeated start–stop and temperature cycling.

2. Corrosion and material selection
   We match tube grades to the service:

   • ASTM A179 / A192 / A210 Gr A1 for clean or mildly corrosive duties

   • ASTM A213 T11 for higher-temperature or mildly corrosive flue gas

   • ASTM A213 TP304 and other stainless or Cu–Ni options for more aggressive media

3. Fouling and cleaning
   Fin height and pitch are selected so that bundles can be cleaned with air, steam or water jets without damaging fins, keeping capacity stable over the life of the exchanger.

4. Cost vs. extruded fins
   KL fin tube offers stronger bonding and better thermal performance than basic L/LL fins, but with lower cost and more material flexibility than fully extruded fins in many applications.

5. Standards and documentation
   Base tubes are produced to ASTM/ASME, EN, JIS, GOST or GB standards with full material test reports and traceability to support international design codes.

Chemical Composition

Mechanical Properties

Applicable Standards and Application Fields

Applicable standards: ASTM/ASME A179, A192, A210, A213; EN 10216 / EN 10217; JIS G3461 / G3462; corresponding GOST and GB finned-tube and air-cooler standards.

Application fields:

• Power generation – air-cooled condensers, boiler gas coolers and waste-heat recovery coils

• Oil and gas / petrochemical – air-cooled heat exchangers, compressor coolers, finned economisers

• Gas processing and LNG – gas coolers and tail-gas heat recovery units

• Chemical and fertilizer plants – reactor gas coolers and overhead condensers

• HVAC and industrial cooling – dry coolers and finned-coil heat exchangers

Q: Are you trading company or manufacturer ?

A: manufacturer,also can do trading.

Q: How long is your delivery time?

A: Generally speaking,it is 10-15 days if the goods are in stock,or it is 30-40 days if the goods are not in stock,

it is according to quantity.

Q: Do you provide samples? is it free or extra ?

A: Yes, we could offer the sample for free charge but need pay the cost of freight.

Q: What is your terms of payment ?

A: Payment<=2000USD, 100% in advance. Payment>=2000USD, 30% T/T in advance ,balance before shippment.

If you have another question, pls feel free to contact with me.