L Type finned tube for heat exchanger is a type of finned tube used in heat exchangers to increase the surface area for heat transfer between the fluid inside the tube and the fluid outside the tube.
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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.
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.
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).
L-Type finned tubes are one of specific types of finned tubes that feature a unique L-shaped fin design. The fins are attached to the outer surface of the tube, forming a series of continuous L-shaped profiles along the length of the tube.
The L-Type finned tubes find application in various industries, including power generation, petrochemical, and HVAC systems. They are commonly used in heat exchangers, air coolers, and condensers, where efficient heat transfer is essential.
The specific design and dimensions of L-Type finned tubes can vary based on the requirements of the application. Factors such as the fluid characteristics, operating temperature, and pressure conditions influence the selection of materials, fin geometry, and fin spacing to optimize heat transfer performance.
The primary purpose of L-Type finned tubes is to enhance heat transfer efficiency. The L-shaped fin design increases the surface area of the tube, improving heat dissipation or heat absorption in applications that require high heat transfer rates.
L-Type finned tubes offer improved heat transfer performance due to their increased surface area. This leads to enhanced heat dissipation or absorption, resulting in improved system efficiency and energy savings.
L-Type finned tubes can be designed to be compatible with various fluids, depending on the selected materials. Different materials such as copper, aluminum, or stainless steel can be used to ensure compatibility with specific fluids and operating conditions.
By enhancing heat transfer efficiency, L-Type finned tubes contribute to improved system performance. They help to maintain optimal temperature levels, enhance overall heat exchange capabilities, and increase energy efficiency.
Transferring heat from a hot fluid into a colder fluid through a tube wall is the reason many of us use finned tubes.
But you may ask, what is the major advantage of using a finned tube? Why can’t you just use a regular tube to make this transfer? Well you can but the rate will be much slower.
By not using a finned tube the outside surface area is not significantly greater than the inside surface area. Because of that, 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 the fluid outside the tube the overall heat transfer rate can be greatly improved by increasing the outside surface area of the tube.
Finned tubes increase outside the surface area. By having a finned tube in place, it increases the overall heat transfer rate. This then decreases the total number of tubes required for a given application which then also reduces overall equipment size and can in the long-run decrease the cost of the project. In many application cases, one finned tube replaces six or more bare tubes at less than 1/3 the cost and 1/4 the volume.
For applications that involve the transfer of heat from a hot fluid to a colder fluid through a tube wall, fin tubes are used. Usually, for an air heat exchanger, where one of the fluids is air or some other gas, the air side heat transfer coefficient will be much lower, so additional heat transfer surface area or a fin tube exchanger is very useful. The overall pattern flow of a finned tube exchanger is often crossflow, however, it can also be parallel flow or counterflow.
Fins are used to increase the effective surface area of heat exchanger tubing. Furthermore, finned tubes are used when the heat transfer coefficient on the outside of the tubes is appreciably lower than that on the inside. In other words, heat transferred from liquid to gas, vapor to gas, such as steam to air heat exchanger, and thermic fluid to air heat exchanger.
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.
A finned tube exchanger typically has tubes with fins attached to the outside. Usually, there will be some liquid flowing through the inside of the tubes and air or some other gas flowing outside the tubes, where the additional heat transfer surface area due to the finned tube increases the heat transfer rate. In a crossflow fin tube exchanger, the fins will typically be radial fins and they’ll either be circular or square in shape.
By not using a finned tube, the outside surface area is not significantly greater than the inside surface area. Because of this, 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 the fluid outside the tube, the overall heat transfer rate can be greatly improved by increasing the outside surface area of the tube.
By having a finned tube in place, it increases the overall heat transfer rate. Finned tubes increase the outside surface area. This decreases the total number of tubes required for a given application which then also reduces overall equipment size and can in the long-run decrease the cost of the project.
Finned tube heat exchangers are used in a variety of applications, and more so as industrial heat exchangers. An air heat exchanger like the evaporator coil in an air conditioning unit is typically a fin tube exchanger. Another common fin tube air heat exchanger is the car radiator. The purpose of the car radiator is to cool the hot water in the tubes with the air passing through the crossflow. On the contrary, the air conditioner evaporator coil has the purpose of cooling the air passing through it. The finned tubes that are manufactured at Kainon Boilers, use high grade carbon steel, stainless steel, copper, brass, and aluminum. Our finned tube exchangers are designed to meet the specific duty condition, temperature and pressure of the fluids.
| Type | Description | Base tube | Fin specification (mm) | ||
| O.D. (mm) | Fin pitch | Fin height | Fin thick | ||
| Embedded | G-type fin tueb | 16-63 | 2.1-5 | <17 | ~0.4 |
| Extruded | Single metal combined metal | 8-51 | 1.6-10 | <17 | 0.2-0.4 |
| Low fin tube t-type fin tube | 10-38 | 0.6-2 | <1.6 | ~0.3 | |
| Bamboo tube corrugated tube | 16-51 | 8-30 | <2.5 | / | |
| Wound | l/kl/ll type fin tube | 16-63 | 2.1-5 | <17 | ~0.4 |
| String | String fin tube | 25-38 | 2.1-3.5 | <20 | 0.2-0.5 |
| U-type | U-type tube | 16-38 | / | / | / |
| Welding | HF-welding fin tube | 16-219 | 3-25 | 5-30 | 0.8-3 |
| H/HH type fin tube | 25-63 | 8-30 | <200 | 1.5-3.5 | |
| Studed fin tube | 25-219 | 8-30 | 5-35 | φ5-20 | |
Four ERW high frequency fining lines, daily capacity around 30 tons.
Three bending machines, maximum OD76*80.
Three ERW studding lines, daily capacity around 100,000 studs.
One DC ERW H/HH fining lines, daily capacity around 20 tons.
Three PLC high speed presser.
Five L/LL/KL/KLM fining lines, daily capacity around 7,000 meters.
Five G fining lines, daily capacity around 5,000 meters.
Ten extrusion fining lines, daily capacity around 15,000 meters.
Hydraulic test lines up to 40MPa.
One under water pneumatic test line.
Computer controlled microscope projector.
One computer controlled pull-off-off tester.
One penetration mirror microscope.
One ultrasonic thickness gauge.
Fin tube boilers represent one of a number of pressurized equipment options used to heat water or convert water into steam under controlled conditions. As in a water tube boiler, water passes through boiler tubes while combustion gases remain in the shell side, passing over the tube surfaces.
For Aluminum L-Foot finned tubes, the fin material is aluminum, either 1100-0. The tube material is generally carbon steel, stainless steel, or brass; however the tube can be of any material.
For Welded Helical Solid and Welded Helical Serrated finned tubes, the fin and tube materials can be any combination that can be welded together using HIGH FREQUENCY WELDING process.
The materials chosen for a given application are a function of service temperature, corrosive environment, and/or erosive environment. Common tube materials used for our welded product lines include: carbon steel, carbon moly, chrome moly, stainless steel, Inconel, and Incoloy. Common fin materials include: carbon steel; stainless steels of types 304, 310, 316, 321, 409, and 410; Nickel 200, and Inconel.
We offer you a broad portfolio of materials and can expand our offering at any time to meet your specific needs regarding thermal conductivity, mechanical properties, or corrosion resistance.
| Material | Grade |
| Carbon Steel Tubes | A179, A192, SA210 Gr A1/C, A106 Gr B, A333 Gr3 Gr6 Gr8, A334 Gr3 Gr6 Gr8, 09CrCuSb, DIN 17175 St35.8 St45.8, EN 10216 P195 P235 P265, GB/T3087 Gr10 Gr20, GB/T5310 20G 20MnG, |
| Alloy Steel Tubes | A209 T1 T1a,A213 T2 T5 T9 T11 T12 T22 T91,A335 P2 P5 P9 P11 P12 P22 P91,EN 10216-2 13CrMo4-5 10CrMo9-10 15NiCuMoNb5-6-4 |
| Stainless Steel Tubes | TP304/304L, TP316/TP316L TP310/310S TP347/TP347H |
| Copper Tubes | UNS12200/UNS14200/UNS70600, CuNi70/30, CuNi 90/10 |
| Titanium Tubes | B338 Gr 2 |
Specific classification of finned tubes, there are lot of types of finned tubes, meanwhile also lot of new species comes up.
And so on.
The material certificate including all the tests can be provided, and also with EN10204 3.1standard.
Отопительные трубы с ребрами обеспечивают хорошую теплопередачу, благодаря абсолютно жесткой посадке плоского ребра на внутренней трубе. Наши отопительные трубы с ребрами применяются везде, где особые условия монтажа требуют использования необычных решений, например, в фасадных системах отопления, на многоярусных складах, в теплицах, при защите стеклянных куполов от запотевания и т.д., также трубы используются для отопления жилых, промышленных и складских помещений. Имеют документированную высокую степень теплоотдачи.
Ребристые трубы монтируются при помощи стандартных фитингов, либо под сварку по желанию Заказчика.
Мы изготавливаем два типоразмера ребристой трубы :
Ду32 и Ду40.
Длину трубы определяет Заказчик.
Покрытие трубы:
-грунт
-порошковая окраска
-горячий цинк.
По ценам и срокам изготовления вы можете узнать, позвонив по телефону
Ребристая труба для отопления на свинокомплексах и птицефабриках
It is fabricated with a batch of single fins that were processed by the punch press and then manually or mechanically, with a certain distance (wingspan) on the base tube.
This is the earliest fin tube fabrication with low cost and simple production process/ technology, easy to maintain. Divides into manual set and mechanical set. Manual set uses a tool that relies on the power of man to press the fins one by one. This method is limited by the pressure of the fin, so it is easy to get loose. The machine – set fin is carried on the wing piece machine. Due to the mechanical impact or liquid pressure, the pressure of the fin is high, so it can be used in a larger volume. The bonding strength between fin and tube is high and not easy to loosen. Mechanical transmission has high productivity, but the noise is large, the safety is poor, and the working conditions of the workers are not good. Although the hydraulic transmission does not have the above problem, but the equipment price is more expensive, the technical requirement to use maintenance personnel is higher, its productivity is also lower.
Currently HF Fin Tube is one of the most widely used helical fin tubes, you can see it as waste heat recovery in power, metallurgy, concrete, oil and gas, petrochemical, etc. When winding the steel strip around steel tube, the use of high frequency current skin effect and proximity effect on steel strip and steel pipe surface heating, until the plastic state or melt, the coil steel belt must be under pressure to complete welding. Comparing with embedded type and spot welding spiral crimped type, it is more advanced either on fin tube quality or production efficiency or automation degree.
The extruded fin is formed from an outer aluminum tube with a large wall thickness (muff), which is aligned over an inner base tube. The two tubes are pushed through three arbors with rotating discs that literally squeeze or extrude the aluminum fins up and out of the muff material in a spiral shape in one operation. Comparing with welding fin tube, dr extruded fin has higher production efficiency with low cost on material and high heat transfer. At present, it divides into copper or aluminum single metal fin tube and bi-metal composited fin tube.
Fin tube manufacturers produce a wide range of fin tubes. They are used in heat exchangers (air, water and chemically cooled) for various industries such as petroleum, petrochemical, steel, power generation and many more.
Corrosion protection processes are performed during fin tube manufacturing and the material used is corrosion resistant. Some fin tube types are:
Helical high finned tubes are used to repair air-cooled heat exchangers and are available in 5 variations
| Type | Photo | Descriptions | Properties |
|---|---|---|---|
| "KL" fin tubes |  |
After application the fin foot is knurled into the corresponding knurling on the base tube thereby enhancing the bond between the fin and tube resulting in improved heat transfer characteristics. Max. operating. temp. 260ºC | Max working temperature – 260 °C (500 °F) Atmospheric corrosion resistance – acceptable Mechanical resistance – acceptable Fin material – aluminum, copper |
| "G" fin tubes |
|
Fin strip is wound & embedded on a groove and securely locked by closing the groove with the base tube metal. This ensures maximum heat transfer at high temperatures. Max. operating temp. 450ºC |
Max working temperature – 400 °C (752 °F) Atmospheric corrosion resistance – poor Mechanical resistance – acceptable Fin material – aluminum, copper, carbon steel |
| "LL" fin tubes |
|
Manufactured in the same way as the ‘L’ fin type except that the fin foot is overlapped to completely enclose the base tube thereby giving excellent corrosion resistance. This type of tube is often used as an alternative to the more expensive extruded type fin in corrosive environments. Max. operating. temp. 180ºC | Max working temperature – 180 °C (356 °F) Atmospheric corrosion resistance – acceptable Mechanical resistance – poor Fin material – aluminum, copper |
| “L” fin tubes | 
|
The strip material is subjected to controlled deformation under tension giving the optimum contact pressure of the foot of the fin onto the base tube thus maximizing the heat transfer properties. The foot of the fin considerably enhances the corrosion protection of the base tube. Max. operating. temp. 150ºC | Max working temperature – 150 °C (302 °F) Atmospheric corrosion resistance – acceptable Mechanical resistance – poor Fin material – aluminum, copper |
| Extruded fin tubes | 
|
This fin type is formed from a bi-metallic tube consisting of an aluminium outer tube and an inner tube of almost any material. The fin is formed by rolling material from the outside of the exterior tube to give an integral fin with excellent heat transfer properties and longevity. Extruded fin offers excellent corrosion protection of the base tube. Max. operating. temp. 280ºC. | Max working temperature – 285 °C (545 °F) Atmospheric corrosion resistance – excellent Mechanical resistance – excellent Fin material – aluminum |
Fin foot is pre-formed into an LL shape (overlapped LL) and applied to base tube under tension. However, foot is pre-shaped to give overlap of one foot onto another, thereby improving base tube protection and thermal contact area Fin materials: Aluminum Base tube materials: Any metallic material. The smooth flat fins perpendicular to the tube surface give rise to very low resistance to air /gas flow and ensure that fouling is kept to a minimum. The foot of the fin is in contact with base tube and provides a complete sheathing over the finned length.
The Overlapped “L” fin design has interlocking fins that are wound together to prevent movement and separation. The fin protects the entire tubes, so the designation works well for the applications where corrosion is a factor.This type of finned tube is often used as an alternative to the more expensive extruded type fin in corrosive environments.
Fin tubes are a type of heat exchanger that is used in many different industries. These tubes have a finned surface, which increases their surface area and allows them to transfer heat more efficiently. This makes them ideal for applications where high heat transfer rates are required, such as in power plants and refrigeration systems.
Fin tubes are made from a variety of materials, including copper, aluminum, and stainless steel. They are available in a range of sizes and shapes and can be customized to meet the specific needs of each application.
One of the key benefits of fin tubes is their ability to operate efficiently at high temperatures and pressures. This makes them suitable for use in a wide range of applications, including air conditioning, heat exchangers, and radiators.
In addition to their high thermal performance, fin tubes are also durable and long-lasting. They are resistant to corrosion and can withstand the harsh environments often found in industrial settings. This makes them a cost-effective solution for many different industries.
The first actual inspection work on the fin tube heat exchanger is the raw materials inspection. Based on the ASME Code, providing material test reports for fin tube heat exchanger plates is mandatory. For other components, the marking inspection will be enough.
The Finned Tube is exposed to the outside to prevent rainwater from falling, try to keep it dry, and it should not be too close to the ground to prevent the irrigation in the greenhouse from corroding the finned tube. After the maintenance of the finned tube, the service life of the finned tube will be greatly increased.
We are a pretty proactive bunch. So, while we do charge a small fee per design to cover our costs, we absorb these costs when it is for a regular customer or where we are working jointly on a project. We also refund the fees in case it is followed by an order.
Absolutely, we can.
Applied Fin Tube is made with strip wrapped under tension around the base of the tube. Fins are welded to the base tube at the strip ends.
Pin Fin tubes are made from wire. Being cylindrical, wire has a larger area per unit of weight than the strip used in L type fin tubes. Also, due to the looped nature of the wire, less material is put on the tube than in the case of L fins. Consequently, the surface area of fins per meter of tubes is also less. However due to the superior turbulence created by the looped wire the actual heat transfer per meter of tube is significantly higher than in the case of L Type Fin Tubes. All of this together contributes to the weight differential between wire wound fin tubes and L Type Fin Tubes. In the case of similar metals, it is weighing half and in the case of Aluminium L fin vs. Steel wire fin they weigh about the same. The higher performance S5 pin fin tubes have an airside heat transfer performance per meter of tube that is 250% of the L type fin tubes.
Yes. A lot of our customer choose to supply their own pipes or tubes, however, a lot of customers ask us to supply them and we are happy to accommodate! We stock various sizes and if we don’t have what you need we can bring it in from one of our many suppliers. If you would like us to include the pipe or tube material in your order, please indicate that when you request a QUOTE.
A continuous helical fin is attached to the base tube by high frequency electric resistance welding in order to give an efficient and thermally reliable bond. Fins can be either solid or serrated (segmented). The weld produced in this process is a true forge, blacksmith weld. This type of weld is comprised of a fusion between two portions of parent metal without the introduction of a filler material. The weld is simply produced by heating the interfaces to be joined to a plastic state and applying pressure.
Used in boilers, furnaces and fired heaters for efficient heat recovery.
The main uses for high frequency welded finned tubes are in the heat recovery associated with boilers for power generation and in furnace applications for the petrochemical industry.
Our finning machines are equipped with online single or duplex cold bending equipment that can manipulate both ends of tubes in a single operation, thus ensuring exact alignment of the ends.
We do not. Our market lends itself to customer designed products, each special in itself. The number of combinations of diameter, overall length, materials and fin specs are too vast. Sunny Steel builds each finned product to each customers needs.
Finned tubes are the main components of heat exchangers. They are a series of tubes where fins have been added on the outside to increase the contact area with the outside fluid, to exchange heat and between the fluid inside the tube and the fluid outside the tube. Finned tubes are elongated aluminium cladded carbon steel flat tubes with brazed aluminium fins.
The rate at which such heat transfer can occur depends on three factors:
Ceramic lined pipe is made through self-propagating high-temperature synthesis (SHS) technique.
Cast basalt lined steel pipe is composed by lined with cast basalt pipe, outside steel pipe and cement mortar filling between the two layers.
Ceramic tile lined pipes have very uniform coating of specially formulated ceramic material that is affixed to the inner of the pipe.
The material of the rare earth alloy wear-resistant pipe is ZG40CrMnMoNiSiRe, which is also the grade of rare earth alloy steel.
Tubes Erosion Shields are used to protect boiler tubing from the highly erosive effects of high temperatures and pressures thereby greatly extending tube life.
The ASTM A213 T91 seamless tubes are primarily used for boiler, superheater, and heat-exchanger.
