Cupro Nickel Flanges
Cupro Nickel Flanges are among the most trusted components used in piping systems that demand high durability, superior corrosion resistance, and strength in extreme conditions. Composed primarily of copper and nickel, with small additions of iron, manganese, and zinc, these flanges are specially designed to withstand the harsh effects of seawater, brine, chemical solutions, and corrosive gases.
They are available in two popular grades: Cu-Ni 90/10 (90% copper and 10% nickel) and Cu-Ni 70/30 (70% copper and 30% nickel). Both types are widely used across industries such as shipbuilding, desalination plants, offshore oil and gas platforms, marine defense, and power generation, owing to their unique blend of toughness and corrosion resistance.
Flanges made from Cupro Nickel provide secure, leak-proof connections between pipes, valves, and other equipment, ensuring uninterrupted fluid flow even under high pressure and temperature fluctuations.
Chemical Composition of Cupro Nickel Flanges
The properties and performance of Cupro Nickel flanges are defined by their carefully balanced chemical composition.
Cupro Nickel 90/10 Flanges
Copper (Cu): 88.6% min
Nickel (Ni): 9–11%
Iron (Fe): 1.8% max
Manganese (Mn): 1.0% max
Zinc (Zn): 1.0% max
Lead (Pb): 0.05% max
Cupro Nickel 70/30 Flanges
Copper (Cu): 65.0% min
Nickel (Ni): 29–33%
Iron (Fe): 0.4–1.0%
Manganese (Mn): 1.0% max
Zinc (Zn): 1.0% max
Lead (Pb): 0.05% max
The 90/10 grade is commonly preferred for general seawater piping, while the 70/30 grade is better suited for environments with more aggressive conditions, such as high-velocity seawater, polluted marine systems, and condenser tubes.
Mechanical Properties of Cupro Nickel Flanges
Cupro Nickel flanges combine strength, toughness, and ductility while offering excellent performance in fluctuating thermal and pressure conditions.
Density: 0.323 lb/in³ at 68 °F
Melting Point: 2260 °F
Tensile Strength: 50,000 psi
Yield Strength (0.2% Offset): 20,000 psi
Elongation: 30%
These properties ensure that the flanges provide long service life, resistance to thermal stress, and the ability to withstand vibration, turbulence, and erosion in marine and industrial applications.
Types of Cupro Nickel Flanges
Cupro Nickel flanges are manufactured in multiple designs to suit different installation and operational requirements. The most common types include:
Slip-On Flanges – Easy to install and weld; suitable for low-pressure applications.
Weld Neck Flanges – Provide strong, stress-resistant connections for high-pressure systems.
Blind Flanges – Used to seal off pipelines or isolate sections for inspection and repair.
Socket Weld Flanges – Ideal for small-diameter, high-pressure piping systems.
Threaded Flanges – Allow easy assembly and disassembly without welding.
Lap Joint Flanges – Commonly used with stub ends where frequent dismantling is required.
Each type of flange is designed with precision, ensuring reliable performance and leak-proof connections in various industrial setups.
Key Features of Cupro Nickel Flanges
Superior Corrosion Resistance – Withstand the effects of seawater, saline solutions, and corrosive gases.
Excellent Mechanical Strength – Ensure durability under high pressure and temperature fluctuations.
Resistance to Biofouling & Erosion – Prevent microbial growth and damage in marine environments.
Thermal Stability – Retain strength and ductility even in fluctuating thermal conditions.
Ease of Fabrication & Weldability – Simple to install, repair, and maintain.
Long Service Life – Reduce the need for frequent replacement and downtime.
Applications of Cupro Nickel Flanges
Due to their durability and resilience, Cupro Nickel flanges are widely used in:
Marine Industry – For seawater cooling, ballast systems, firewater systems, and shipbuilding.
Desalination Plants – Handle saline water in evaporation and reverse osmosis units.
Oil & Gas Industry – Used in offshore rigs and pipelines exposed to corrosive seawater.
Power Generation – For condensers, heat exchangers, and cooling water piping.
Chemical Processing – Handle corrosive chemicals, brine, and acidic solutions.
Defense & Naval Sector – Extensively used in submarines, naval ships, and marine defense systems.
Advantages of Cupro Nickel Flanges
High resistance to seawater corrosion and stress cracking.
Superior strength and toughness for high-pressure systems.
Extended service life with reduced maintenance needs.
Cost-effective compared to exotic alloys like titanium or Hastelloy.
Excellent reliability in both static and dynamic fluid systems.
Conclusion
Cupro Nickel Flanges are a vital component for industries that rely on durable, corrosion-resistant, and high-strength piping connections. Whether in marine systems, offshore oil rigs, desalination plants, or chemical processing units, these flanges deliver reliability, safety, and efficiency.
Available in 90/10 and 70/30 grades, Cupro Nickel flanges are engineered to provide leak-proof, long-lasting connections while standing strong against erosion, biofouling, and thermal stress. With their exceptional chemical and mechanical properties, they remain one of the most cost-effective and performance-driven choices for industries worldwide.
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Explore moreFAQs - Cupro Nickel Flanges
Cupro Nickel flanges are used in marine, oil and gas, desalination, and power industries where high corrosion resistance, durability, and leak-proof piping connections are essential.
Cupro Nickel flanges are primarily available in 90/10 (Cu-Ni 90-10) and 70/30 (Cu-Ni 70-30) grades, both offering superior corrosion resistance and mechanical strength.
Cupro Nickel flanges resist seawater corrosion, biofouling, erosion, and stress cracking, making them highly reliable for marine cooling, ballast, firewater, and desalination piping systems.
Cupro Nickel flanges possess 50,000 psi tensile strength, 20,000 psi yield strength, 30% elongation, and excellent thermal stability, ensuring long service life in demanding environments.
They are extensively used in shipbuilding, desalination plants, offshore oil and gas platforms, chemical processing, power generation systems, and naval defense applications for reliable piping connections.
Common types include slip-on, weld neck, blind, socket weld, threaded, and lap joint flanges, each designed for specific piping requirements and industrial applications.
Cupro Nickel’s copper-nickel alloy with trace elements provides excellent resistance against seawater, brine, stress corrosion cracking, and erosion, even in polluted and high-velocity marine environments.
Yes, Cupro Nickel flanges are cost-effective due to their long service life, reduced maintenance needs, and reliability compared to exotic alloys like titanium and Hastelloy.
Absolutely, Cupro Nickel flanges are engineered for high-pressure and temperature applications, ensuring leak-proof, durable, and safe connections in demanding fluid handling systems.
70/30 grade offers greater resistance to high-velocity seawater and polluted environments, while 90/10 grade is cost-effective and suitable for standard seawater systems.