L Type Finned Tube,Wrapper Fin tube Wound Fin Tube

L Type Finned Tube for Heat Exchanger
L Type Finned Tube is a finned tube made of aluminum fin tape or copper fin tape folded into an L-shaped spiral under tension and wrapped tightly around the outer surface of the base tube.

The tension in the fin strips of the L Type Finned Tube wraps around the tube, causing the fin feet to press forcefully against the tube, holding the fins firmly in place. L Type Finned Tube is usually used in air coolers in petrochemical, power, paper, tobacco, building heating and other industries as well as heat exchangers in power plants (electricity, nuclear, thermal and geothermal power plants), the maximum operating temperature can reach 230°C.

L Type Finned Tube for Heat Exchanger Quick Details:
Fin type: Solid plain
Fin Tube Type:L Type
Outer diameter (OD): 16mm Min~50.8mm max.
Tube length: up to 18,000 mm.
Fin height: 16.5mm max.
Fin thickness: generally 0.4mm~0.6mm
Fin pitch: 2.1mm minimum (12FPI)
Surface Protection: Both bare ends shall be zinc or aluminum metallized by electrospray arc system coating.
Accessories: Tube support boxes, clamps or spacer boxes (materials: aluminium, zinc and stainless steel).

Common Specifications of L Type Finned Tube for Heat Exchanger

We can customize L Type Finned Tube for heat exchanger according to your drawings
Example:

Manufacturing Process:
Fin strips (usually aluminum and copper) are folded into an L shape and wound under tension on the surface of the base tube. The feet of the fins are connected together and cover the surface of the fins.

L Finned Tube is combined with two different materials
Core tube material: carbon steel, low alloy steel, stainless steel, brass, copper, copper-nickel alloy, aluminum bronze, nickel alloy.

Fin material: aluminum, copper, steel
1. Aluminum (Alu.1100, Alu.1060)
2. Copper.
3. Steel

Quality Control
Inspection and Tests Performed
Chemical Composition inspection,
Mechanical Properties Test(Tensile Strength, Yield Strength, Elongation, Flaring, Flattening, Hardness, Impact Test), S
surface and Dimension Test,
No-destructive Test,
Hydrostatic Test.

Delivery conditions
The tube ends are square cut without burrs, the inside is dry and blown clean, and the ends of the L-shaped tension wound finned tube are coated with varnish on the outside.

Acceptance Criteria
API Standard 661 (Air-Cooled Heat Exchangers for General Refinery Service) or Delivery Conditions (TDC).

Features of L Type Finned Tube
1. The trapezoidal section formed by the calendering of L Type Finned Tube for heat exchanger is consistent with the distribution of heat flow density, the tubes are tightly combined, and the thermal efficiency is high, which eliminates the contact heat caused by the gap between the tubes and the finned tube. resistance, the fin spacing is uniform, and the heat transfer performance is good.
2. The tube can withstand temperatures up to 150°C and there is no risk of atmospheric corrosion or thermal stress.
3. The L-type finned tube provides the contact area between the fin strip and the surface of the tube to protect the tube wall from atmospheric corrosion.
4. This L TYPE design is much more economical than LL, KL or even G-embedded types.
5. Maximum operating temperature: 230°C

Application of L Type Finned Tube
1. Highly corrosive systems (condenser, evaporator, desalination, fertilization, urea system, ammonia, gas, corrosive acid);
2. Air coolers in petrochemical, electric power, paper, tobacco, building heating and other industries;
3. Air heaters and air heaters for spray drying systems such as vegetable protein powder and starch in the food industry;
4. Heat exchanger installations in power plants (electrical, nuclear, thermal and geothermal power plants).

Additional Info
Payment Terms:T/T, LC
Delivery: 15-30 days after payment
Marking: Standard + Steel Grade + Size + Heat No + Lot No
Package: Iron frame packing boxes and the desiccants are put into each package for continental transportation as well. or as required

Wound sheet type The L type fin tube wound tube is easy to manufacture and cheap, and it is widely used in air coolers for petrochemical industry. However, because the aluminum sheet is fastened to the surface of the steel pipe by the initial stress of winding, when the temperature of the pipe wall is high, the tension of the fin is greatly reduced, the fin starts to loosen, and the contact thermal resistance increases, so its use temperature is relatively low, generally low At 130°C.
Therefore, the L type finned tube wound tube is suitable for occasions with relatively stable working conditions and no sudden changes in temperature; it is also not suitable for occasions with large vibrations. The base tube is partially covered by the bent legs between the fins, and its resistance to atmospheric corrosion is general, which is between the DR type and the G type.