Embedded Knurled Fin Tube
About Us
Dellok(YONGHUI Radiating Pipe Manufacturing Co.,Ltd) was established in 2002, which is located in Nanjing, China.We joined HARBIN AIR CONDITIONING CO., LTD. in 2022 and became the most professional industry manufacturer in China. After many years of development, the company now has 66 million yuan in fixed assets, more than 200 employees, and 33 technical staffs. We have 4 aluminum processing production lines, with the annual processing capacity of more than 20,000 tons; And we have 5 tube-drawing production lines; 47 fintube production lines, 1 imported production line from American with the brand of McElroy , with the annual production capacity of 12 million meters the above.

Embedded Finned Tube
Finned tube is a tube with small finned fins around its outer surface. These fins act as a filter and a mechanism for transferring heat from the material inside the tube to or from the outer space. Finned tubes are used in applications where heat is transferred from a hot fluid to a cooler fluid through the wall of the tube. The rate at which this heat transfer occurs depends on three factors:
The difference in temperature between the two fluids.
The coefficient of heat transfer between each fluid and the wall.
Surface area of fluid exposure.
L type fin tube: Adopting the winding process, the production efficiency is high, uniform lamella distance , good heat transfer, high finization ratio, the base tube can be protected from air erosion. The aluminum fin or copper fin is folded into an L shape and continuously spirally wound on the outer surface of the base tube under the action of tension.
Maximum working temperature-150°C (302°F), acceptable for atmospheric corrosion resistance, poor mechanical resistance. Commonly used heat sink materials are aluminum and copper.
LL typefinned tube: Under the L-shaped foundation, the fin root completely covers the outer surface of the base tube; to some extent, this fin type guarantees better corrosion resistance. Maximum working temperature-180°C (356°F), acceptable for atmospheric corrosion resistance, poor mechanical resistance. Commonly used heat sink materials are aluminum and copper
KL type finned tube: Before the fins are continuously wound on the surface of the steel pipe, the outer surface of the base pipe needs to undergo a knurling process; after the fins are wound, the root of the fin attached to the steel pipe will also be knurled to strengthen the steel pipe and Combination of fins. For this reason, this fin type ensures better heat transfer characteristics under the fins of L and LL. Maximum working temperature-260°C (500°F), acceptable for atmospheric corrosion resistance, poor mechanical resistance. Commonly used heat sink materials are aluminum and copper.
Finned Tube applications
Application: Mainly used in air coolers in petrochemical, electric power, paper making, tobacco, building heating and other industries, air heaters and air heaters in spray drying systems such as vegetable protein and starch in the food industry. Blast furnace and converter systems, power generation: condensate exhaust gas discharged from steam turbines, condensate contact cycle cooling condensation, fossil and nuclear power plants, air conditioners (Freon, ammonia, propane), waste incineration equipment, compressor coolers, etc.
We customized finned tube according to customer indivisual requirement, for more details about L/LL/KL Finned Tube please inquire us!

Product Description
Fin Type: L/LL/KL Finned Tube
Tube Material: Carbon steel, stainless steel, copper, aluminum
Fin Material: Copper, aluminum
Fin Tube Length: No Limit
Working temperature: 230℃.
Features: Adopting the winding process, the production efficiency is high, the lamella distance is uniform, the heat transfer is good, the finization ratio is high, the base tube can be protected from air erosion.

L type finned tube:
Adopting the winding process, the production efficiency is high, uniform lamella distance , good heat transfer, high finization ratio, the base tube can be protected from air erosion. The aluminum fin or copper fin is folded into an L shape and continuously spirally wound on the outer surface of the base tube under the action of tension.
Maximum working temperature-150°C (302°F), acceptable for atmospheric corrosion resistance, poor mechanical resistance. Commonly used heat sink materials are aluminum and copper.

FAQ
1. What is a fin tube?
A fin tube, whether baseboard or convector-style, is a heating element, made of copper or steel, for a piping system. It has square or spiral aluminum "fins" that radiate (distribute) the heat and are low to the floor. Fin tubes replaced radiators in the 1940s and 50s and were popular before forced air systems became common.
2. Why use finned tubes?
Finned tubes are used in applications involving the transfer of heat from a hot fluid to a colder fluid through a tube wall. The rate at which such heat transfer can occur depends on three factors: (1) the temperature difference between the two fluids; (2) the heat transfer coefficient between each of the fluids and the tube wall; and (3) the surface area to which each fluid is exposed. In the case of a bare (unfinned) tubes, where the outside surface area is not significantly greater than the inside surface area, the fluid with the lowest heat transfer coefficient will dictate the overall heat transfer rate. When the heat transfer coefficient of the fluid inside the tube is several times larger than that of fluid outside the tube (for example steam inside and oil outside), the overall heat transfer rate can be greatly improved by increasing the outside surface of the tube. In mathematical terms, the product of heat transfer coefficient for the outside fluid multiplied by the outside surface area is made to more closely match the product of the inside fluid heat transfer coefficient multiplied by the inside surface area.
So the whole concept of finned tubes is to increase the outside surface area of the tube. As an example, a finned tube configuration of 2” (nominal, 2.375” actual) pipe with a ¾” high welded helical solid fin of 12 gauge thickness with 6 fins per inch has an outside surface area of 8.23 sq. ft. per linear foot; whereas the same bare pipe has an outside surface area of only .62 sq. ft. per linear foot. That is a 13X increase in outside surface area.
By increasing the outside surface area of the tube, the overall heat transfer rate is increased, thereby reducing the total number of tubes required for a given application. This reduces the overall equipment size and the cost of the project. In many cases, one finned tube replaces six or more bare tubes at less than 1/3 the cost and ¼ the volume.
3. What is Tension Wound Fin Tubes?
The Tension Wound Fin means the fins wrapped tightly around the tube and welded or stapled at the ends of tubes to hold the form. Tension Wound Fins can also be solder-coated to strength the corrosion resistance. Tension wound fin works especially prefer with fins and tubes that are use the same material.
There are 4 types of tension wound fin tubes in our factory:
A. L finned tube
B. LL finned tube
C. KL finned tube
D. Crimped finned tube