ASTM A376 TP347H HFW Finned Tube with C.S. Fins for Waste Heat Recovery Plants

ASTM A376 TP347H HFW Finned Tube with C.S. Fins for Waste Heat Recovery Plants

1. Product Overview (Original Unique Writing, Rich Long-Tail Keywords)

Our ASTM A376 TP347H HFW finned tube is a premium bimetallic heat transfer assembly purpose-built for high-temperature flue gas, waste heat recovery and process cooling services, where the pressure boundary base pipe demands superior stabilized stainless steel performance while carbon steel fins deliver economical, high thermal conductivity for enhanced air-side heat exchange. Unlike all-stainless finned tubes, this hybrid construction pairs a niobium-stabilized TP347H austenitic stainless steel base tube with helically high-frequency welded carbon steel fins, striking an optimal balance between high-temperature creep resistance, intergranular corrosion protection and project cost control.

The base tube strictly complies with ASTM A376, the governing specification for seamless austenitic stainless steel tubing intended for high-temperature central station power, boiler and pressure piping service. The carbon steel fin strip is continuously helically wrapped and high-frequency fusion welded onto the outer tube wall, forming a rigid metallurgical bond that eliminates contact thermal resistance. This bimetallic HFW finned tube retains the outstanding high-temperature strength and sensitization resistance of TP347H for the wetted pressure boundary, while carbon steel fins offer excellent heat conduction, easy fabrication and outstanding abrasion resistance against particulate-laden flue gas. It maintains reliable thermal performance under sustained operating temperatures ranging from 450°C up to 850°C.

This TP347H base / carbon steel fin HFW finned tube is a core component for utility boiler economizers, high-temperature waste heat boilers, process air coolers, flue gas heat recovery systems, thermal oil heat exchangers and petrochemical process coolers. It is widely selected for projects where the process side requires stabilized stainless steel to resist intergranular corrosion after prolonged thermal exposure, yet the gas side does not require full stainless steel cladding. Our production supports fully customized dimensions: base tube outer diameter, wall thickness, fin height, fin pitch, bare unfinned end length and overall tube length; full MTR material test reports, PMI verification and hydrostatic test records are supplied for every shipment.

Core Product Code Breakdown

• ASTM A376 TP347H HFW: High-frequency welded fin construction on seamless TP347H base tube, UNS S34779 niobium-stabilized austenitic stainless steel, certified to ASTM A376 specification for high-temperature pressure tubing
• Finned Tube: Helical high-frequency resistance welded solid spiral fin structure
• C.S. Fins: Carbon steel fin strip, cost-effective, high thermal conductivity for gas-side heat transfer

Base Tube

TP347H Base Tube Chemical Composition Table (ASTM A376 Standard, wt.%)

Note: Niobium is added to combine preferentially with carbon, suppressing chromium carbide precipitation during repeated high-temperature thermal cycling. This stabilization eliminates the risk of intergranular corrosion after weld exposure or long hold times in the sensitization temperature window, making TP347H superior to standard 304H for high-temperature boiler and power piping.

TP347H Base Tube Mechanical Properties Table (Room Temperature, ASTM A376 Minimum Values)

Additional mechanical feature: TP347H possesses excellent long-term creep rupture strength under sustained high-temperature pressure load, the key reason it is specified for superheater, reheater and waste heat boiler tubing.

3. Production & Structural Specifications

Manufacturing Process

1. Seamless TP347H stainless steel tubing manufactured and solution annealed to ASTM A376 for uniform grain structure and stabilized corrosion resistance

2. Carbon steel fin strip helically wound tightly around the outer surface of the base tube

3. High-frequency resistance fusion welding creates a continuous metallurgical bond between carbon steel fin and stainless steel base tube

4. Deburring, dimensional inspection, hydrostatic pressure test, PMI material positive identification, marking and final packing

4. Key Competitive Advantages

• TP347H niobium-stabilized base tube: Outstanding resistance to intergranular corrosion after thermal sensitization, reliable creep strength for continuous high-temperature pressure service
• Economical carbon steel fins: High thermal conductivity, lower material cost, good wear resistance against ash and dust in flue gas streams
• HFW fusion weld between fin and tube: Metallurgical bonding with minimal contact resistance, stable heat transfer performance over decades of operation
• Bimetallic optimized design: Separates pressure boundary material requirement from gas-side fin material, avoiding over-specification and reducing total project investment
• Full ASTM A376 traceability: Complete chemical, mechanical and non-destructive documentation for power, boiler and ASME code projects
• Flexible custom manufacturing: Adjustable fin geometry, plain end sections and total lengths to match customer heat exchanger and boiler layout
• Rigorous quality control: Hydrostatic test, PMI, visual and dimensional inspection for every tube bundle

5. Industrial Application Scenarios

This ASTM A376 TP347H HFW finned tube with carbon steel fins serves demanding high-temperature thermal equipment globally:

• Power Generation: Utility boiler superheater/reheater auxiliary heat transfer sections, HRSG waste heat recovery bundles, biomass boiler flue gas coolers
• Petrochemical Industry: High-temperature process air coolers, reformer waste heat recovery, heavy oil reboiler cooling circuits
• Waste Heat Recovery Plants: High-temperature flue gas heat exchangers, thermal oil furnaces, exhaust energy recovery for industrial kilns
• Chemical Processing: High-temperature reaction medium coolers, sulfur recovery unit heat transfer bundles
• Energy & Heavy Industry: Cogeneration plant heat exchangers, incinerator flue gas cooling, high-temperature air preheaters