C71500 Copper Nickel Tubes PDF
C71500 Copper Nickel Size & Price PDF
Key takeaways
CuNi 90/10 is cost-effective and offers good corrosion resistance and thermal conductivity - ideal for standard marine piping and heat exchangers.
CuNi 70/30 provides higher strength and superior resistance in aggressive or high-velocity seawater environments - preferred for offshore and desalination systems.
Choosing the right alloy depends on the operating environment, mechanical demands, and budget considerations.
Copper-nickel (CuNi) alloys are renowned for their exceptional resistance to corrosion, especially in marine environments. Among these, the 90/10 and 70/30 compositions are the most prevalent, each offering distinct properties that make them suitable for specific applications.
Chemical Composition and Alloying Elements
CuNi 90/10 (C70600): Comprises approximately 90% copper and 10% nickel, with small additions of iron and manganese to enhance corrosion resistance and mechanical strength.
CuNi 70/30 (C71500): Contains about 70% copper and 30% nickel, along with slightly higher amounts of iron and manganese compared to the 90/10 alloy. This composition provides superior strength and resistance to aggressive environments.
Mechanical Properties
| Property | CuNi 90/10 | CuNi 70/30 |
|---|---|---|
| Tensile Strength (MPa) | ~310 | ~360 |
| Yield Strength (MPa) | ~100 | ~130 |
| Elongation (%) | ~30 | ~30 |
| Hardness (HB) | ~80 | ~100 |
Corrosion Resistance in Marine Environments
Both CuNi 90/10 and 70/30 alloys are highly resistant to corrosion in seawater, a property enhanced by the formation of a protective oxide layer on their surfaces. However, their performance differs under specific conditions:
CuNi 90/10: Suitable for environments with moderate flow rates and less aggressive conditions. It performs well in clean seawater applications.
CuNi 70/30: Offers superior resistance to high-velocity seawater, polluted marine environments, and areas prone to biofouling. Its higher nickel content and alloying elements contribute to this enhanced performance.
In terms of maximum allowable flow velocities:
CuNi 90/10: Up to 3.5 m/s for piping systems.
CuNi 70/30: Up to 4.0 m/s for piping systems.
Exceeding these velocities can lead to erosion-corrosion, so selecting the appropriate alloy based on flow conditions is essential.
Thermal and Electrical Conductivity
| Property | CuNi 90/10 | CuNi 70/30 |
|---|---|---|
| Thermal Conductivity (W/m·K) | ~50 | ~29 |
| Electrical Resistivity (μΩ·cm) | ~19 | ~34 |
CuNi 90/10 has higher thermal conductivity, making it more efficient for heat transfer applications. However, CuNi 70/30's lower thermal conductivity is offset by its superior strength and corrosion resistance, which are critical in more aggressive environments.
Fabrication and Weldability
Both alloys are known for their excellent fabrication properties:
Formability: CuNi 90/10 is more malleable, allowing for easier bending and forming, which is advantageous in complex installations.
Weldability: Both alloys can be welded using standard techniques. However, it's recommended to use 70/30 filler material when welding either alloy to ensure optimal joint strength and corrosion resistance.
Work Hardening: Neither alloy can be strengthened by heat treatment, but their strength can be increased through cold working processes.
Cost considerations
The cost difference between the two alloys is primarily due to their nickel content:
CuNi 90/10: More cost-effective, making it suitable for large-scale projects where budget constraints are a concern.
CuNi 70/30: Higher cost due to increased nickel content, but offers better performance in challenging environments, justifying the investment for critical applications.
Typical applications
| Application | Preferred Alloy |
|---|---|
| Seawater piping systems | CuNi 90/10 |
| Heat exchangers and condensers | CuNi 90/10 |
| Offshore oil and gas platforms | CuNi 70/30 |
| Desalination plants | CuNi 70/30 |
| Shipbuilding (hull cladding, seawater systems) | CuNi 70/30 |
| Power plant cooling systems | CuNi 90/10 |
Real-world applications and case examples
CuNi 90/10 and 70/30 alloys have been extensively used in critical infrastructure projects across marine, power generation, and offshore sectors. For example, CuNi 90/10 is widely used in shipbuilding for seawater piping systems, bilge lines, and ballast systems. Its balance of corrosion resistance and cost-efficiency makes it ideal for large commercial vessels and naval ships where extensive piping is needed.
In contrast, CuNi 70/30 is often found in high-performance environments such as offshore oil rigs, FPSOs (Floating Production Storage and Offloading units), and desalination plants. These systems demand higher mechanical strength and better protection against harsh seawater and biological growth. In desalination plants, for instance, CuNi 70/30 is used in multi-stage flash (MSF) and reverse osmosis systems due to its excellent resistance to erosion from high-velocity brine.
Power plants located in coastal areas also use both alloys-CuNi 70/30 is typically reserved for condenser tubes that face direct exposure to seawater cooling loops, while CuNi 90/10 is used for less exposed systems. These real-world uses illustrate how critical the right alloy selection is for long-term performance and cost optimization.
Our spot inventory
| ASME SB111 CuNi 90/10 |
C71500 seamless condenser tube |
CuNi 90/10 welded copper nickel pipe |
| ASTM B111 CuNi 70/30 |
ASTM B466 C71500 pipe |
CuNi 70/30 cupronickel boiler tube |
| 70/30 copper nickel pipe |
CuNi 90/10 heat exchanger tube |
C71500 welded copper nickel pipe |
| SB111 UNS CuNi 90/10 |
70/30 cupronickel condenser tube |
ASTM B111 CuNi 90/10 heat exchanger tube |
|
CuNi 90/10 copper nickel pipe |
ASTM B111 CuNi 70/30 heat exchanger tube |
ASME SB111 CuNi 70/30 copper nickel pipe |
About us
Gnee is a premier manufacturer and international supplier of comprehensive copper and copper alloy products, committed to delivering excellence in copper tubes, copper sheets, copper plates, copper bars, copper rods, copper wires, and copper strips.
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We supply a full range including **Capillary Tubes, Thin-Walled Copper Tubes, Thick-Walled Copper Tubes, Round Pipes, Square Pipes, Rectangular Pipes, Welded Pipes, Seamless Pipes, Heat Exchanger Tubes, and Condenser Tubes.
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Common Alloys & International Standards:
We master a wide array of materials compliant with ASTM, EN, JIS, and GB standards:
Pure Copper: C11000 (ETP Copper), C10200 (Oxygen-Free Copper), C12000 (DLP)
Brass Alloys: C26000 (Cartridge Brass), C27200 (Brass), C28000 (Muntz Metal)
Copper-Nickel: C70600 (CuNi90/10), C71500 (CuNi70/30)
Phosphor Bronze: C51900, C52100, C54400
Serving industries from HVAC/R and plumbing to electrical, automotive, and marine engineering, Gnee provides OEM support, competitive pricing, and reliable bulk supply for your global projects.
