TOBO Industrial (Shanghai) Co., Ltd., a premier manufacturer and global supplier of precision-engineered metal products, has announced the expansion of its advanced alloy portfolio with the introduction of 2mm Square and Rectangular Tubes manufactured from premium Alloy CuNi 90/10 (C70600) and 70/30 (C71500) . These precision-formed nickel-copper tubes are specifically engineered for high-efficiency cooling fin applications across marine, power generation, chemical processing, and industrial heat exchange systems worldwide.
Material Science Excellence: The Copper-Nickel Advantage for Cooling Fins
The newly launched tubes leverage the distinct advantages of premium copper-nickel alloys, which have been trusted for decades in demanding marine and offshore environments . Both C70600 (90/10) and C71500 (70/30) alloys are renowned for their exceptional combination of thermal conductivity, corrosion resistance, and mechanical durability.
C70600 (90% Copper, 10% Nickel) – Optimal Balance of Performance and Cost:
Thermal Conductivity: Approximately 40 W/m·K, providing efficient heat transfer for cooling applications
Corrosion Resistance: Excellent resistance to seawater corrosion, biofouling, and impingement attack, with typical rates below 0.025 mm per year in marine environments
Mechanical Properties: Tensile strength of 275-450 MPa, elongation of 30-45%, yield strength of 105-170 MPa
Applications: Condensers, seawater-cooled heat exchangers, and general marine cooling systems
C71500 (70% Copper, 30% Nickel) – Premium Grade for Maximum Performance:
Thermal Conductivity: Approximately 29 W/m·K, suitable for high-temperature applications
Superior Corrosion Resistance: Enhanced resistance to high-velocity seawater, acids, and sulfide-containing environments. Of all commercial copper alloys, C71500 offers the best resistance to aqueous corrosion
Enhanced Strength: Tensile strength of 400-515 MPa, yield strength of 170-380 MPa, significantly higher than 90/10 alloy
High-Temperature Stability: Maintains mechanical properties in continuous service up to 400°C
Applications: Offshore oil and gas platforms, naval vessels, chemical processing equipment, and critical heat exchangers
Both alloys exhibit outstanding resistance to chloride-induced stress corrosion cracking—a common failure mode for stainless steels—and their natural biofouling resistance minimizes maintenance requirements in seawater service .
Precision Geometry: The 2mm Square and Rectangular Advantage for Cooling Fins
The specific focus on 2mm square and rectangular profiles represents a significant engineering advancement for cooling fin design . These compact, precision-formed tubes offer multiple performance benefits over traditional round tubing:
Enhanced Surface Area Contact: The flat surfaces of square and rectangular tubes maximize thermal contact with brazed or mechanically attached cooling fins, improving overall heat transfer efficiency by approximately 25-40% compared to equivalent round tubes
Space Optimization: The compact 2mm profile enables higher-density heat exchanger designs, crucial for space-constrained applications in shipbuilding, offshore platforms, and advanced electronics cooling
Improved Structural Integrity: The geometry provides enhanced rigidity and resistance to deformation under pressure or thermal cycling while maintaining excellent ductility for fabrication
Superior Fluid Dynamics: Controlled corner radii optimize the balance between pressure drop and heat transfer efficiency, ensuring consistent performance throughout the system's service life
Uniform Wall Thickness: Precision manufacturing ensures consistent 2mm wall thickness, providing predictable heat transfer characteristics and reliable pressure containment
Manufacturing Precision and Quality Assurance
TOBO's CuNi square and rectangular tubes are produced using advanced precision extrusion and cold-drawing processes, resulting in exceptional dimensional accuracy and surface finish . Each tube undergoes rigorous quality control protocols to ensure compliance with international standards:
Applicable Specifications:
ASTM B111 / ASME SB111: For copper and copper-alloy seamless condenser tubes
ASTM B466 / ASME SB466: For seamless copper-nickel pipe and tube
EN 12451 / DIN 86019: For marine and industrial heat exchanger tubes
Quality Assurance Measures:
100% Dimensional Verification: Laser micrometer systems ensuring compliance with specified tolerances
Eddy Current Testing: Non-destructive examination for surface and internal defects per ASTM E243
Hydrostatic Pressure Testing: Verification of pressure integrity
Chemical Analysis: Spectrochemical verification of alloy composition per heat lot
Mechanical Testing: Tensile, yield, and elongation verification per applicable standards
Key Technical Specifications:
Parameter C70600 (90/10) C71500 (70/30)
Wall Thickness 2mm (±0.05mm) 2mm (±0.05mm)
Profile Options Square & Rectangular Square & Rectangular
Thermal Conductivity ~40 W/m·K ~29 W/m·K
Tensile Strength 275-450 MPa 400-515 MPa
Yield Strength 105-170 MPa 170-380 MPa
Elongation 30-45% 30-40%
Max Service Temp 300°C 400°C
Temper Options Annealed (O61) or Light-Drawn (H55) Annealed (O61) or Light-Drawn (H55)
Industry Applications: Meeting Critical Cooling Demands
These specialized square and rectangular tubes are engineered for mission-critical cooling applications across multiple industries:
Marine and Offshore Engineering:
Shipboard cooling systems and engine heat exchangers requiring long-term seawater service
Offshore platform equipment and hydraulic system cooling
Naval vessel systems where reliability and corrosion resistance are paramount
Seawater-cooled condensers for marine propulsion systems
Power Generation and Energy Systems:
Power station condensers and auxiliary cooling units
Renewable energy systems, including solar and wind power electronics cooling
Generator and transformer cooling systems
Heat recovery steam generator (HRSG) components
Chemical and Process Industries:
Process heat exchangers handling corrosive media
Pharmaceutical manufacturing equipment requiring corrosion-resistant thermal management
Desalination plant heat recovery and rejection system components
Chemical reactor cooling coils and jacketing
Transportation and Advanced Electronics:
Electric vehicle battery and power electronics thermal management
Aerospace avionics and hydraulic system cooling
Data center cooling systems requiring compact, efficient heat exchange
Railway traction system cooling components
HVAC and Refrigeration:
Large-scale chiller heat exchanger tubes
Condenser and evaporator coils for commercial refrigeration
Heat pump heat exchanger components
Cooling Fin Integration: Optimal Design Considerations
The square and rectangular profile of these tubes is specifically optimized for cooling fin attachment:
Fin Attachment Methods: Compatible with mechanical expansion, brazing, or welding for fin-to-tube bonding
Fin Materials: Compatible with copper, aluminum, or stainless steel cooling fins
Tube Pitch Optimization: The square profile allows for consistent, predictable tube spacing in fin bundles
Enhanced Heat Transfer: The flat surfaces provide superior contact area compared to round tubes, reducing thermal interface resistance
Total Cost of Ownership and Sustainability Advantages
While CuNi alloys command a higher initial material cost compared to alternatives such as aluminum or carbon steel, the Total Cost of Ownership (TCO) presents compelling economic justification for cooling fin applications:
Extended Service Life: Demonstrated 25-40 year service life in seawater applications, eliminating frequent replacement cycles associated with aluminum or carbon steel heat exchangers
Reduced Maintenance: Natural corrosion and biofouling resistance minimize cleaning requirements, chemical treatments, and inspection frequency, reducing annual maintenance costs by up to 60% compared to conventional materials
Sustained Efficiency: Less than 5% heat transfer degradation over 10,000 hours in simulated seawater service ensures consistent thermal performance throughout system lifetime
Complete Recyclability: 100% recyclable without degradation of material properties, supporting circular economy principles and sustainable infrastructure development
Energy Savings: Maintained thermal efficiency throughout service life reduces pumping and cooling energy requirements, contributing to lower operational expenses
Comparative Advantages Over Alternative Materials
Property CuNi 90/10 (C70600) Aluminum 6061 316 Stainless Steel
Thermal Conductivity 40 W/m·K 167 W/m·K 16 W/m·K
Seawater Corrosion Excellent Poor Moderate
Biofouling Resistance Excellent Poor Poor
Max Service Temp 300°C 200°C 800°C
Relative Cost Moderate Low High
While aluminum offers higher thermal conductivity, its poor corrosion resistance in marine environments leads to rapid degradation and frequent replacement. CuNi alloys provide the optimal balance of thermal performance and corrosion resistance for long-life cooling applications .
Global Supply and Availability
TOBO maintains substantial inventory of precision-drawn CuNi square and rectangular tubes, with efficient logistics networks serving international markets. Key manufacturing clusters in China, particularly in Shanghai and Jiangsu provinces, have developed advanced metallurgical facilities capable of producing these high-performance tubes with integrated R&D, precision drawing, and non-destructive testing (NDT) capabilities .
Ordering Information:
Minimum Order Quantity: Flexible, with sample orders negotiable
Delivery Time: 15-60 working days depending on quantity and specifications
Payment Terms: T/T, L/C, Western Union
Shipping Terms: FOB Shanghai, CIF, CFR, Ex-Work available
TOBO welcomes inquiries for custom specifications, including non-standard dimensions, special tempers, and project-specific certification requirements.
Conclusion: Setting a New Benchmark in Compact Heat Exchanger Technology
The introduction of Alloy CuNi 90/10 C70600 and 70/30 C71500 2mm Square and Rectangular Tubes for Cooling Fins represents a significant advancement in thermal management technology for demanding environments. By combining the proven corrosion resistance of copper-nickel alloys with optimized square/rectangular geometry and precision manufacturing, TOBO is enabling a new generation of compact, efficient, and durable heat exchangers .
As global industries face increasing challenges from energy efficiency requirements, environmental regulations, and operation in aggressive marine and industrial environments, these specialized tubes provide engineers and system designers with a reliable, high-performance solution that addresses multiple performance dimensions simultaneously—thermal efficiency, corrosion resistance, mechanical strength, and lifecycle value .
About TOBO Industrial (Shanghai) Co., Ltd.
TOBO is a professional manufacturer and exporter of precision-engineered metal products based in Shanghai, China. With robust production capacity and a commitment to metallurgical excellence, TOBO serves customers worldwide across marine, energy, chemical, and industrial sectors. The company specializes in copper-nickel alloys, nickel alloys, stainless steels, and associated products for demanding applications, with strict quality control and complete traceability .