Copper nickel pipe, also known as cupronickel pipe or CuNi pipe, is specially designed for seawater service and marine environments. Copper nickel alloys contain copper, nickel, iron and manganese, which provide excellent corrosion resistance and good mechanical performance in seawater applications.

Compared with carbon steel and some stainless steels, copper nickel pipe performs well in chloride-containing seawater environments. It can form a stable protective surface film in seawater, helping to reduce corrosion, erosion and marine organism attachment. For this reason, CuNi pipe is commonly used in shipbuilding, offshore engineering, desalination systems and heat exchanger equipment.With excellent resistance to seawater corrosion, erosion corrosion and marine biofouling, copper nickel pipe is one of the preferred materials for marine piping applications.

We supply 90/10 copper nickel pipes and 70/30 copper nickel pipes in grades such as C70600, C71500, CuNi10Fe1Mn and CuNi30Mn1Fe. Seamless pipes, welded pipes, heat exchanger tubes and matching copper nickel pipe fittings are available according to ASTM, DIN, EN, EEMUA and customer project requirements.

Available Copper Nickel Pipe Products

We supply a wide range of copper nickel pipes and tubes for marine and offshore piping systems.

90/10 Copper Nickel Pipe C70600

70/30 Copper Nickel Pipe C71500

DIN 86019 Copper Nickel Pipe

Common Material Grades

90/10 Copper Nickel Pipe vs 70/30 Copper Nickel Pipe

90/10 copper nickel pipe, usually supplied as C70600 or CuNi10Fe1Mn, contains approximately 90% copper and 10% nickel. It offers excellent seawater corrosion resistance, good weldability and cost-effective performance. It is widely used in shipbuilding and general marine piping systems.

70/30 copper nickel pipe, usually supplied as C71500 or CuNi30Mn1Fe, contains approximately 70% copper and 30% nickel. Compared with 90/10 CuNi, it provides higher strength and better resistance to erosion corrosion, making it suitable for higher velocity seawater systems and more demanding marine environments.

Standards

Our marine copper nickel pipes can be supplied according to the following standards or customer specifications:

• ASTM B466

• ASTM B467

• ASTM B111

• ASME SB466

• DIN 86019

• DIN 86090

• EEMUA 144

• EN 12449

• EN 12451

• GB/T standards

Specifications

Matching Copper Nickel Pipe Fittings

In addition to copper nickel pipes, we also supply matching CuNi pipe fittings for complete marine piping solutions:

• Copper nickel elbows

• Copper nickel tees

• Copper nickel reducers

• Copper nickel flanges

• Copper nickel caps

• Copper nickel stub ends

• Copper nickel couplings

• Copper nickel unions

• Custom CuNi pipe fittings

• Copper nickel fabricated pipe spools
  
  

Seamless Copper Nickel Pipe Production Process

For copper nickel seamless pipe, the typical production process includes billet inspection, heating, hot extrusion or piercing, cold drawing, intermediate annealing, final sizing, heat treatment, straightening, cleaning, inspection and packaging.

Seamless copper nickel pipes are widely used for marine pressure piping, heat exchangers, condensers and critical seawater systems where uniform structure and reliable performance are required.

Flow Chart

Raw Material Inspection → Heating → Hot Extrusion / Piercing → Cold Drawing / Cold Rolling → Annealing → Straightening → Pickling / Cleaning → Cutting → Testing → Marking → Packaging

Welded Copper Nickel Pipe Production Process

For copper nickel welded pipe, copper nickel strips or plates are formed into tubular shape and welded longitudinally. After welding, the pipe can be heat treated, sized, straightened and inspected according to the required standard.

Welded copper nickel pipes are suitable for large diameter seawater piping systems, shipbuilding pipelines and offshore engineering projects.

Flow Chart

Strip / Plate Inspection → Slitting → Forming → Longitudinal Welding → Weld Treatment → Sizing → Annealing → Straightening → Cleaning → Testing → Marking → Packaging

Quality Control and Inspection

To ensure reliable performance in marine environments, our copper nickel pipes can be supplied with necessary inspection and test reports according to customer requirements.

Available inspections include:

• Chemical composition analysis

• Mechanical property test

• Dimensional inspection

• Visual inspection

• Hydrostatic test

• Eddy current test

• Ultrasonic test

• Flaring test

• Flattening test

• PMI test

• Material test certificate

• Third-party inspection report

• Classification society inspection, if required
  
  

Packaging and Delivery

Marine copper nickel pipes are packed carefully to prevent damage, contamination and deformation during transportation. Standard packaging includes wooden cases, wooden pallets, bundles with protective wrapping and export seaworthy packing.

For precision tubes or heat exchanger tubes, additional protection such as end caps, plastic film, moisture-proof paper or individual separation can be provided according to customer requirements.