ASTM A312 TP347H HFW Solid Finned Tube with SS304 Fins For Air preheaters

ASTM A312 TP347H HFW Solid Finned Tube with SS304 Fins For Air preheaters

A High Frequency Welded (HFW) solid finned tube is a type of heat exchanger tube commonly used in various industrial processes where heat must be efficiently transferred from one medium to another (for instance, from a gas to a liquid, or vice versa). These tubes are designed to improve the heat transfer efficiency by increasing the surface area of the tube that is in contact with the fluid to be cooled or heated.

The "solid finned" description refers to the fins being solid, meaning they are made from the same material as the tube and are integral to it. The finned structure is manufactured through a high-frequency electrical resistance welding process, which is efficient and results in high-quality, consistent fin-to-tube bond. No filler material is used, resulting in a cleaner, more robust construction that provides excellent heat transfer characteristics and resistance to corrosive environments.

ASTM A312 TP347H HFW Solid Finned Tube with SS304 Fins is a specialized type of heat exchanger tubing designed for high-temperature and corrosive environments. Here's a breakdown of its components:

1. Chemical Composition of ASTM A312 TP347H (Weight %)

Notes:

• Niobium (Nb) requirement: Minimum Nb must be 10 times the carbon content (e.g., if C=0.08%, Nb ≥ 0.8%).
• Stabilization: Nb (Columbium) prevents chromium carbide precipitation (sensitization) during welding or high-temperature exposure.

2. Mechanical Properties of ASTM A312 TP347H

Additional Notes:

• High-Temperature Suitability: TP347H is designed for elevated temperatures (up to 800°C / 1472°F), with superior creep resistance due to higher carbon and niobium content.
• Heat Treatment: Solution annealed at ≥ 1040°C (1900°F) followed by rapid cooling for optimal corrosion resistance.

Comparison with Non-"H" Grade (TP347)

Key Applications of TP347H

• Power Plants: Superheater tubes, reheater coils.
• Oil & Gas: Refinery heaters, cracking tubes.
• Chemical Processing: High-temperature reactors.

3. Key Features of A312 TP347H Solid Finned Tube with SS304 Fins

• High-Temperature Performance: TP347H base tube resists oxidation and creep in boilers, superheaters, and heat recovery systems.
• Corrosion Resistance: Suitable for acidic, sulfurous, or chloride-containing environments (e.g., power plants, refineries, chemical processing).
• Enhanced Heat Transfer: Fins increase surface area, improving thermal efficiency in air-cooled heat exchangers, economizers, or waste heat recovery units.

4. Why This Combination(A312 TP347 Base Tube+ SS304 Fins)?

• TP347H Base Tube: High creep strength and oxidation resistance.
• SS304 Fins: Cost-effective corrosion resistance for fin-side exposure (e.g., air, mild corrosive gases).
• HFW (High-Frequency Welded): Balances performance and cost vs. seamless tubes.
• Solid Fins: Durable under thermal cycling/vibration vs. wrapped fins.

The ASTM A312 TP347H HFW Solid Finned Tube with SS304 Fins is specifically designed for high-efficiency heat transfer in high-temperature and corrosive environments. Its key applications include:

1. Power Generation (Boilers & Superheaters)

• Superheater/Reheater Tubes: Resists steam oxidation and creep at temperatures up to 800°C (1472°F) in coal-fired, gas-fired, and waste-to-energy plants.
• Heat Recovery Steam Generators (HRSGs): Recovers waste heat from gas turbines, where SS304 fins enhance air-side heat transfer.

2. Petrochemical & Refining

• Fired Heaters & Cracking Furnaces: Handles high-temperature hydrocarbon streams (e.g., ethylene production) where TP347H’s Nb stabilization prevents sensitization.
• Sulfur Recovery Units (SRUs): Resists acidic condensates and thermal cycling.

3. Waste Heat Recovery Systems

• Economizers/Air Preheaters: SS304 fins (good formability, cost-effective) maximize heat exchange in flue gas applications.

4. Chemical Processing

• ​High-Temperature Reactors: Used in nitric acid, fertilizer, and hydrogen plants where corrosion resistance to oxidizing media is critical.