C71500 CuNi 70/30 Copper Nickel Tube for Marine Water Piping with High Tensile

Product Specification

C71500 CuNi 70/30 Cupronickel Seamless Tube Marine Water Piping Anti-Corrosion Pipe

1.Product Description

Copper nickel tube (also known as cupronickel tube) is a copper-based alloy tubing with nickel as the primary alloying element, typically containing 5% to 30% nickel. The most commercially common grades are 90-10 (10% nickel) and 70-30 (30% nickel) copper-nickel alloys, with small but important additions of iron and manganese to optimize corrosion resistance. These alloys exhibit a uniform face-centered cubic (FCC) structure that provides high toughness and excellent resistance to seawater corrosion. The tubes are available in both seamless and welded forms, complying with standards such as ASTM B466 (seamless) and ASTM B467 (welded). Copper-nickel tubes feature a silver-white metallic luster, with higher nickel content resulting in a whiter appearance.

2.Product Applications

Copper nickel tubes are widely used in marine and industrial environments where corrosion resistance is critical. The main applications for 90-10 and 70-30 copper-nickel alloys include:

• Seawater piping systems – cooling water, firewater, and ballast systems on ships and offshore platforms

• Heat exchangers and condensers – in power generation, chemical processing, and marine engineering

• Desalination plants – multi-stage flash (MSF) and multiple effect distillation (MED) systems

• Offshore oil and gas platforms – seawater cooling and firewater/deluge systems

• Shipbuilding – hulls, platform riser and leg sheathing, oil coolers

• Hydraulic tubing – including brake tubing for vehicles

• Chemical processing and power generation – heat transfer equipment and corrosion-resistant piping

3.Product Advantages

Excellent corrosion resistance – Copper-nickel alloys exhibit exceptional resistance to seawater corrosion, with general corrosion rates ranging between 0.025 and 0.0025 mm/year. The alloys form stable, adherent protective films composed of copper oxides and nickel-enriched compounds that continue to grow and self-heal during seawater exposure.

Superior biofouling resistance – The alloy resists marine organism attachment and biofouling, making it ideal for long-term seawater exposure.

High strength and durability – Both alloys have good mechanical strength and ductility, with 70-30 alloy possessing greater inherent strength. Strength can be further increased by work hardening.

Excellent thermal conductivity – 90-10 alloy has a thermal conductivity of approximately 50 W·m⁻¹·K⁻¹, while 70-30 alloy offers about 29 W·m⁻¹·K⁻¹, ensuring efficient heat exchange.

Good weldability and formability – The tubes can be welded, bent, flared, and processed through plastic deformation.

Long service life – Seawater piping systems using copper-nickel tubes have extended service lives, directly impacting vessel availability and lifecycle costs.

​4.Key Product Specifications

FAQ

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2.How long is your delivery time? Generally it is 5-10 days if the goods are in stock. or it is 15-20 days if the goods are not in stock, it is according to quantity.

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