1. Basic Definition & Structure

H-type finned tube (also called square finned tube) is a high-efficiency welded heat transfer component, named after its symmetrical H-shaped rectangular fins welded onto the base tube via resistance welding.

It has two mainstream structures:

• Single H Finned Tube: One base tube clamped and welded by a pair of symmetrical rectangular fins, forming an H outline.

• Twin H (HH) Finned Tube: Two parallel base tubes share one set of double-sided H fins, with higher structural rigidity, widely adopted in power plant economizersAlibaba.co....

Main raw materials:

• Base tube: Carbon steel (A106, A179, A210), alloy steel, stainless steel (TP304/316L), ND anti-corrosion steel; OD 25–73mm, wall thickness 2.0–16mm.

• Fin strip: Carbon steel or stainless steel strip; fin thickness 1.5–3.5mm, fin pitch 8–50mm, fully customizable per drawingsAlibaba.co....

Manufacturing process: Symmetric steel strips wrap the tube outer wall → full resistance welding for metallurgical integration → cutting, shaping, pressure inspection, anti-rust treatment. The tight welding joint eliminates air gaps, greatly lowering thermal resistance between fins and tube.

2. Core Advantages

(1) Ultra-high Heat Transfer Efficiency

H-shaped rectangular fins multiply the outer heat exchange area, with the heat transfer surface up to 7–8 times that of smooth bare tubes. Straight parallel airflow channels strengthen flue gas disturbance, significantly lifting overall heat exchange coefficient and cutting equipment footprint.

(2) Anti-fouling & Self-cleaning Performance

Parallel straight flue gas passages between fins avoid ash dead zones. High-speed flue gas continuously scours fin surfaces, minimizing fly ash adhesion. It delivers outstanding soot-blowing effect, effectively preventing blockage in high-dust flue gas environments.

(3) Low Flue Gas Resistance & Energy Saving

Streamlined fin layout reduces airflow pressure drop, lessening the load of induced draft fans and auxiliary power consumption, lowering long-term operating costs.

(4) Excellent Wear & Vibration Resistance

Integrated full welding enhances overall structural strength. The tube bundle layout reduces local flue gas velocity, cutting abrasion loss. Its service life is 3–4 times longer than smooth tubes in coal-fired, biomass and waste incineration boilers, slashing maintenance and replacement expenses.

(5) High Thermal Stability

The solid metallurgical welding bond resists thermal fatigue and fin detachment under repeated heating & cooling cycles, stably operating under working temperatures up to 450℃.

3. Working Principle

Heat medium (water, steam) flows inside the base tube, while high-temperature flue gas passes outside the H fins. The extended fin surface greatly enlarges the contact area between flue gas and metal wall. Heat rapidly transfers from flue gas to the internal medium through fins and tube wall, realizing efficient waste heat recovery and energy recycling.

4. Main Application Scenarios

1. Power Industry: Economizers, low-temperature flue gas waste heat recovery systems of coal-fired, biomass and waste-to-energy power plants; air preheaters.

2. Industrial Boilers: Waste heat boilers, furnace tail heat recovery for chemical, metallurgy, cement and kiln industries.

3. Petrochemical Industry: High-temperature gas coolers, sulfur condensers, process waste heat recycling equipment.

4. Marine Equipment: Compact marine boiler economizers with strict space limits.

5. HVAC & Heat Exchange: Industrial air coolers, heating heat exchangers.

5. Short Version (For Product Catalog / Inquiry Email)

H-type Finned Tube

H-type finned tube is a welded square fin heat exchanger element, available in single H and twin HH types. Symmetrical rectangular fins are fully resistance-welded on base tubes for zero thermal resistance.

Key strengths: Large heat transfer area, low gas flow resistance, self-cleaning & anti-ash accumulation, strong wear resistance and long service life. Widely used as boiler economizer and flue gas waste heat recovery parts in power, chemical, metallurgical and marine industries. All sizes and materials can be customized according to client technical drawings and working conditions.