TOBO Industrial (Shanghai) Co., Ltd., a global leader in precision-engineered metal products, has announced the expansion of its advanced piping portfolio with the introduction of high-quality seamless copper-nickel alloy pipes in grades C70600 (90/10), CuNi 70/30, and CuNi 90/10, available in diameters ranging from 1 inch to 24 inches with a standard pressure rating of 20Pa. These precision-engineered round tubes are manufactured to meet the most demanding requirements of marine, offshore, power generation, and industrial processing applications where corrosion resistance and long-term reliability are paramount .
Material Science Excellence: Understanding Copper-Nickel Alloys
Copper-nickel alloys, particularly the 90/10 and 70/30 variants, are widely recognized for their outstanding performance in aggressive environments, especially in seawater and marine applications. These alloys contain carefully controlled additions of iron and manganese, which are essential for maintaining optimal corrosion resistance .
C70600 (90/10 Copper-Nickel): This alloy, containing approximately 90% copper and 10% nickel with 1.0-1.8% iron, is the most commonly used wrought copper alloy for marine engineering applications . It offers excellent resistance to seawater corrosion with rates typically below 0.025 mm per year, natural biofouling resistance, and thermal conductivity of approximately 40 W/m·K . C70600 is ideally suited for seawater cooling systems, desalination plants, marine piping, and power plant condensers .
C71500 (70/30 Copper-Nickel): The premium-grade alloy contains 29-33% nickel and 0.4-1.0% iron, delivering enhanced corrosion resistance in harsh marine environments, particularly against high-velocity seawater and aggressive chemical conditions . It is stronger than 90-10 copper-nickel and can resist higher flow rates . With tensile strength of 310-380 MPa and yield strength of 110-170 MPa, C71500 is preferred for offshore oil and gas platforms, naval vessels, and chemical processing equipment requiring maximum durability .
Both alloys demonstrate excellent 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 .
Comprehensive Size Range and Technical Specifications
TOBO's new seamless copper-nickel pipes are available in a complete range of dimensions to suit diverse application requirements:
Diameter Range: 1 inch to 24 inches (DN25 to DN600), covering the full spectrum of industrial piping needs
Pressure Rating: 20Pa standard, with higher ratings available for specialized applications
Wall Thickness Options: Schedule 5S through XXS, accommodating various pressure and service requirements
Lengths: Standard random lengths of 18-24 feet, with cut-to-size options available
Temper Options: Annealed (soft) for maximum formability, or light-drawn for enhanced strength
End Finish: Plain end, beveled end, or custom configurations as specified
Mechanical Properties:
Tensile Strength: 310-380 MPa (45-55 ksi) depending on temper and alloy
Yield Strength: 110-170 MPa (16-25 ksi)
Elongation: 30-40% in 2 inches, ensuring excellent ductility for fabrication
Hardness: 60-90 HRB, providing good wear resistance
Temperature Range: Stable performance from -50°C to 300°C
Manufacturing Excellence: The Seamless Advantage
TOBO's copper-nickel pipes are manufactured using advanced seamless extrusion and cold-drawing processes, ensuring maximum structural integrity and dimensional precision . Unlike welded alternatives, seamless construction eliminates potential weak points associated with longitudinal weld seams, resulting in homogeneous microstructure and uniform corrosion resistance throughout the pipe .
Production Process:
Seamless Extrusion: Hot extrusion of cast billets creates the initial tubular form with refined grain structure
Cold Drawing and Pilgering: Multiple cold-working passes achieve precise dimensional control and enhanced mechanical properties
Solution Annealing: Controlled heat treatment relieves internal stresses and restores ductility for optimal performance
Surface Enhancement: Advanced finishing processes create smooth internal and external surfaces ideal for fluid transport applications
Quality Assurance and International Standards Compliance
TOBO's seamless copper-nickel pipes are manufactured and tested to meet rigorous international standards:
Applicable Specifications:
ASTM B466 / ASME SB466: Standard specification for seamless copper-nickel pipe and tube
ASTM B111 / ASME SB111: Standard for copper and copper-alloy seamless condenser tubes
EEMUA 144 / 234: Recommended practice for copper-nickel fabrication for offshore applications
EN 12451: Copper and copper alloys - seamless, round tubes for heat exchangers
Comprehensive Testing Protocol:
100% Ultrasonic Testing: For wall thickness uniformity and detection of internal defects
Eddy Current Testing: Non-destructive examination per ASTM E243 standards
Hydrostatic Pressure Testing: Verification to 1.5 times working pressure
Chemical Analysis: Spectrochemical verification for each heat lot, ensuring precise alloy composition
Mechanical Testing: Tensile, yield, and elongation verification per applicable standards
Dimensional Verification: Laser micrometer systems ensuring compliance with specified tolerances
Certification Options:
TOBO provides comprehensive documentation including Mill Test Certificates (MTCs) and can arrange EN 10204 Type 3.1 or 3.2 certification through independent third-party inspection by recognized agencies such as SGS, BV, or TUV upon request .
Industry Applications Across Critical Sectors
These high-quality seamless copper-nickel pipes serve essential functions across multiple industries where corrosion resistance and reliability are paramount:
Marine and Offshore Engineering:
Seawater cooling systems for main engines and auxiliary equipment on commercial and naval vessels
Ballast water management and firefighting systems
Offshore platform piping and subsea equipment
Shipbuilding and repair applications requiring long-term seawater service
Desalination and Water Treatment:
Multi-stage flash (MSF) evaporator and condenser tubing
Reverse osmosis (RO) plant high-pressure piping
Brine heater and heat recovery sections
Intake and discharge lines handling high-salinity seawater
Power Generation:
Steam condenser tubing in coastal and nuclear power plants
Heat exchanger systems and feedwater heaters
Cooling water systems for thermal power stations
Auxiliary cooling circuits requiring corrosion-resistant materials
Oil and Gas Industry:
Offshore topside and subsea piping systems
Seawater injection lines for reservoir pressure maintenance
Process cooling and heat exchanger applications
Firewater systems on platforms and FPSO vessels
Chemical and Industrial Processing:
Heat exchanger and condenser tubes for corrosive media
Process piping in chemical plants handling aggressive fluids
Pharmaceutical manufacturing equipment requiring corrosion-resistant materials
Pollution control and industrial heat recovery systems
Performance Advantages and Total Cost of Ownership
TOBO's seamless copper-nickel pipes deliver significant advantages over alternative materials:
Corrosion Performance:
Seawater corrosion rate: <0.025 mm per year, ensuring decades of reliable service
Excellent resistance to pitting, crevice corrosion, and stress corrosion cracking
Superior performance in sour service (H₂S) environments
Natural resistance to biofouling and marine growth, reducing maintenance requirements
Comparative Advantages:
50% longer service life than stainless steel in marine environments
40% better heat transfer efficiency compared to stainless steel alternatives
Superior erosion-corrosion resistance in high-velocity flow conditions
Better performance in polluted or brackish water applications
Economic Benefits:
Reduced maintenance costs through natural corrosion and biofouling resistance
Extended replacement intervals, minimizing lifecycle costs
Higher operational reliability, reducing unplanned downtime
Lower total cost of ownership despite premium initial investment
EEMUA 234 Compliance for Offshore Applications
For demanding offshore projects, TOBO's copper-nickel pipes can be supplied in accordance with EEMUA Publication 234, the comprehensive specification for copper-nickel alloy piping for offshore applications . This standard ensures:
Strict chemical composition controls with optimized iron and manganese content
Enhanced corrosion resistance for aggressive offshore environments
Rigorous testing requirements including corrosion testing per ASTM G48 where specified
Full traceability with EN 10204 3.1 or 3.2 certification
Sustainability and Environmental Responsibility
TOBO's copper-nickel pipes align with global sustainability objectives:
100% Recyclable: At end of service life, the alloy can be reprocessed without loss of quality, contributing to circular economy principles
Extended Service Life: Long operational lifespan reduces material consumption and waste generation compared to frequently replaced alternatives
Reduced Chemical Usage: Natural biofouling resistance minimizes need for toxic antifouling coatings and biocidal treatments
Energy-Efficient Manufacturing: Modern production facilities employ optimized processes reducing carbon footprint
RoHS and REACH Compliance: Products meet environmental safety regulations for restricted substances
Global Supply and Availability
TOBO maintains substantial inventory of ASTM B466-compliant seamless copper-nickel pipes, with efficient logistics networks serving international markets. The global copper-nickel pipe market is experiencing significant growth, with projected 6.8% CAGR through 2028 driven by expanding offshore energy projects, desalination plants, and shipbuilding activities . The Asia-Pacific region currently holds approximately 45% market share, reflecting the region's dominant position in shipbuilding and industrial development .
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, 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 Standard for Critical Piping Systems
The introduction of high-quality seamless copper-nickel alloy pipes in C70600, CuNi 70/30, and 90/10 grades from 1" to 24" represents a significant advancement in materials technology for demanding industrial applications. By combining the proven corrosion resistance of copper-nickel alloys with seamless construction and rigorous quality assurance, TOBO provides engineers and procurement specialists with reliable solutions for critical fluid transport systems.
Whether specified for seawater cooling systems on offshore platforms, high-pressure piping in desalination plants, or critical connections in power generation facilities, these pipes deliver the longevity, reliability, and performance that modern industry demands.
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.