Finned Tubes(Heat Pipe System) for Heating Agricultural Greenhouses
With the rapid development of modern agriculture, livestock and poultry greenhouses have become vital facilities for ensuring the supply of agricultural products during winter. However, maintaining a stable temperature within the greenhouse to provide a comfortable growth environment for animals during the cold winter months poses a significant challenge for farmers. In recent years, finned tubes—a type of highly efficient, energy-saving heating equipment—have seen widespread adoption in these greenhouses.
1. Core Structure and Working Principle
A finned tube consists of two parts: a base tube and external fins. The base tube is typically made of seamless steel and serves to transport a heating medium, such as hot water or steam. Densely arranged metal fins (usually made of steel or aluminum strips) are welded or rolled onto the exterior. This structure increases the heat dissipation surface area by four to six times—or even more—compared to traditional bare tubes. As the heating medium flows through the tube, heat is conducted from the base tube to the fins and then rapidly dissipated into the air. This process significantly boosts heat exchange efficiency, achieving rates three to five times higher than standard bare-tube radiators.
2. Main Manufacturing Types
Finned Tubes for Heating Agricultural Greenhouses Specifications
| Parameter | Extruded Finned Tubes | High-Frequency Welded (HFW) Fin Tubes | Hot-Dip Galvanized Finned Tubes |
| Base Tube Materials | Stainless steel, carbon steel, alloy | — | — |
| Base Tube Outer Diameter (OD) | 12 mm – 60 mm | 16 mm – 273 mm (Common: 25–159 mm / DN25–DN108) | 16 mm – 273 mm (Common: 25–159 mm / DN25–DN108) |
| Base Tube Wall Thickness | — | 2 mm – 8 mm (Customizable based on pressure) | 2 mm – 8 mm (Customizable based on pressure) |
| Fin Height | 7 mm – 16 mm | 5 mm – 30 mm (Generally ≤ base pipe radius) | 5 mm – 30 mm (Generally ≤ base pipe radius) |
| Fin Thickness | 0.25 mm – 1.0 mm | 0.6 mm – 2.5 mm | 0.6 mm – 2.5 mm |
| Fin Pitch | 2.3 mm – 5.0 mm | 5 mm – 25 mm (Common: 5, 6, 8, 10, 12 mm) | 5 mm – 25 mm (Common: 5, 6, 8, 10, 12 mm) |
| Fin Materials | Aluminum, copper | — | — |
| Length | — | Customizable up to 30 m or longer | Customizable up to 30 m or longer |
Based on manufacturing processes, the finned tubes commonly used in agricultural greenhouses fall into the following categories:
High-frequency welded finned tubes: These utilize the skin effect and proximity effect of high-frequency current to heat the steel strip and steel tube to a plastic state before pressure-welding them together. Characterized by a high weld fusion rate and a tight bond, they are currently the mainstream choice for greenhouse heating. Common specifications include DN65×2.5; they offer high-temperature resistance, corrosion resistance, and excellent sealing properties.
Hot-dip galvanized finned tubes: These are produced by applying a hot-dip galvanizing treatment to the surface of cold-wound or high-frequency welded finned tubes. They exhibit excellent corrosion and weather resistance, effectively withstanding the corrosive effects of fertilizer vapors and moisture within the greenhouse, and offer a service life of over 15 years.
Steel-aluminum composite bimetallic finned tubes (rolled/extruded): These are created using a mechanical rolling process that tightly bonds an aluminum strip to the outer wall of a steel tube, forming an integrated structure. Aluminum features high thermal conductivity and rapid heat dissipation; its seamless construction eliminates the risk of rust, making it particularly suitable for high-humidity environments.
3. Design and Installation of Finned-Tube Heating Systems
Design: When designing a finned-tube heating system, the quantity and specifications of the tubes must be determined based on factors such as the greenhouse area and height, as well as the type and number of animals housed. Additionally, the selection and layout of the heat source must be considered to ensure heat is evenly distributed to every corner of the greenhouse.
Installation: During installation, appropriate spacing must be maintained between the finned tubes and the greenhouse walls or support structures to facilitate air circulation and heat dissipation. Proper securing and connection of the tubes are also essential to ensure system reliability.
4. Performance Advantages
High Efficiency and Energy Saving: High heat exchange efficiency allows for rapid temperature increases within the greenhouse, reducing energy consumption. Compared to traditional heating methods, heat utilization rates are significantly improved, lowering operating costs.
Precise Temperature Control: Even heat dissipation without “dead zones” effectively prevents excessive localized temperature differences. This helps maintain the optimal growth temperature range of 15–30°C for crops, protecting them against frost damage and late-spring cold snaps.
Strong Adaptability: The compact structure does not encroach on planting space and allows for flexible installation along the perimeter, at the top, or between crop rows. The corrosion-resistant material withstands high-humidity and dusty greenhouse environments and is resistant to dust accumulation.
Convenient Installation: Flange connections are commonly used, making assembly, disassembly, maintenance, and management easy.
5. Application Scenarios
Widely used in glass greenhouses, plastic tunnels, and seedling propagation facilities for vegetables, flowers, and nursery stock. It is particularly effective in cold northern regions, ensuring successful overwintering and off-season production. By improving seedling emergence rates, yields, and produce quality, it serves as vital infrastructure for increasing agricultural output and profitability. 6. Maintenance and Care of Finned-Tube Heating Systems
Regular Inspection: Conduct periodic inspections of the finned-tube heating system, checking the condition of the finned-tube surfaces, looking for loose connections, and verifying the proper operation of the heat source.
Cleaning and Maintenance: Regularly clean both the exterior and interior of the finned tubes to prevent dust and debris from clogging the pipes and impairing heat dissipation. Additionally, perform maintenance on the heat source to ensure the system operates stably over the long term.
7. Rigorous Inspection and Certification by SGS, BV, and ISO
To ensure superior quality and performance, Datang’s finned tubes undergo rigorous inspection by globally recognized quality assurance authorities—SGS, BV, and ISO. This independent verification process ensures that every aspect of the finned tubes—from material composition to manufacturing tolerances—meets the strictest international standards. Certification marks from SGS, BV, and ISO provide customers with peace of mind, assuring them that they are investing in a product of impeccable quality and reliability. With such stringent quality control, you can be confident that our finned tubes will not only meet or exceed your expectations but also deliver stable, high-efficiency heat transfer performance.
8. Specifications and Design Features
These finned tubes utilize standard specifications common to heat transfer tubing and are precision-engineered to optimize heat transfer performance across various operating conditions. Their dimensions strike an ideal balance between flow velocity, pressure drop, and heat transfer surface area, ensuring outstanding performance in diverse thermal systems. The fin design further enhances overall performance by increasing the effective heat transfer surface area. The layout and geometry of the fins are meticulously crafted to disrupt fluid flow, promote turbulence, and intensify convective heat transfer. This design facilitates efficient heat exchange between the tube wall and the surrounding fluid, thereby maximizing the system’s overall thermal efficiency.
9. Brand Identity and Origin
Our finned heat transfer tubes bear the renowned “Datang” trademark, symbolizing a legacy of excellence and innovation. The “Datang” brand is synonymous with quality and reliability, enjoying an industry-wide reputation for delivering cutting-edge heat transfer solutions. Manufactured in China—a global manufacturing hub—these finned tubes benefit from deep engineering expertise and advanced production processes. This powerful combination of a prestigious brand and China’s robust manufacturing capabilities ensures that customers receive products that are not only technologically advanced but also backed by strong brand credibility and a reliable supply chain. 10. Production Capacity and Supply Capability
Datang Finned Tube boasts a robust annual production capacity of 800,000 finned tubes, fully capable of meeting the needs of projects ranging from small-scale applications to large-scale engineering undertakings. Leveraging advanced manufacturing equipment and efficient production processes, we guarantee the timely delivery of high-quality finned tubes. As a professional Chinese manufacturer, we meet requirements with the highest standards—whether for small-batch orders needed for prototype testing or high-volume demands for major industrial facilities. Furthermore, we utilize specially designed plywood packaging to safeguard the products during transit, ensuring they arrive in perfect condition and are ready for immediate installation and use.
In summary, finned-tube systems designed for agricultural greenhouses are highly efficient, energy-saving, and durable heat-exchange units, specifically engineered to address the challenge of maintaining warmth in greenhouses during winter or low-temperature conditions. By significantly increasing the heat dissipation surface area, they facilitate rapid heat transfer and uniform distribution, serving as essential equipment for maintaining optimal crop growth temperatures in modern agriculture.