ASTM B466 CuNi 70/30 Copper Nickel Alloy Pipe C71500 Seamless for Marine Offshore

ASTM B466 CuNi 70/30 Copper Nickel Alloy Pipe C71500 Seamless for Marine Offshore

Copper Nickel Pipe is a corrosion-resistant tubular product made from a copper matrix with nickel as the primary alloying element. CuNi 70/30 (UNS C71500) contains approximately 29.0–33.0% nickel, with small additions of iron and manganese, offering higher strength, superior resistance to high-velocity seawater impingement corrosion, and excellent cavitation resistance. It can be produced in seamless or welded forms and meets international standards such as ASTM B466, ASTM B467, ASTM B111, and ASME SB466. Compared with CuNi 90/10, CuNi 70/30 is more suitable for high-flow, sand-containing, turbulent, and harsh seawater conditions, and is widely used in shipbuilding, marine engineering, power generation, nuclear power, desalination, and chemical heat exchange equipment.

2.Product Applications

Key applications of CuNi 70/30 copper nickel pipe include:

1. Shipbuilding & Marine Engineering: Seawater cooling lines, ballast water piping, fire main systems, bilge lines, deck wash systems, and high-velocity seawater pipelines on offshore platforms.

2. Power Generation & Nuclear Power: Condenser tube bundles, auxiliary cooling circuits, lube oil coolers, heat exchangers, and seawater cooling systems in nuclear power plants.

3. Desalination: Heat exchanger tubes, intake and outfall lines for MSF, MED, and RO plants.

4. Oil & Gas: Seawater injection, cooling, fire-fighting, and produced-water treatment piping on offshore platforms, FPSOs, and LNG modules.

5. Chemical & Process Industry: Distillation towers, reactors, seawater-cooled heat exchangers, condensers, and corrosion-resistant piping systems.

6. Marine Components: Seawater pump bodies, valve bodies, fittings, propeller shaft sleeves, and high-corrosion-resistant structural parts.

3.Product Advantages

1. Excellent High-Velocity Seawater Corrosion Resistance: CuNi 70/30 can withstand relatively high seawater flow rates, typically 3.0–4.5 m/s, while maintaining stable corrosion resistance under sand-containing and turbulent conditions.

2. Outstanding Cavitation & Crevice Corrosion Resistance: Compared with CuNi 90/10, 70/30 is less prone to cavitation and localised corrosion under high-flow and pressure-variation environments.

3. High Strength & Good Toughness: Annealed tensile strength of approximately 350–480 MPa, yield strength of 105–205 MPa, and elongation of 20–40%, combining strength and ductility.

4. Inherent Biofouling Resistance: Copper ion release inhibits marine organism attachment, reducing biocide dosing and shutdown cleaning frequency.

5. Good Weldability & Fabrication: Supports TIG/MIG welding, cold drawing, annealing, bending, flaring, and deep drawing; can be successfully welded to steel.

6. Long Service Life: Can reliably serve in seawater environments for over 20 years with low maintenance costs.

7. Wide Temperature Adaptability: Operating range of approximately -100°C to 371°C, with no low-temperature brittleness and stable high-temperature performance.

​4.Key Product Specifications

​