High-Quality Seamless and Welded Pipes for Marine and Industrial Applications
Copper nickel pipes are made from an alloy of copper and nickel, with strengthening elements like manganese and iron. Despite high copper content, copper nickel pipes have a silver color. These alloys have proven to be highly resistant to seawater, brine water, organic compounds, salts, and diluted non-oxidizing acids.
Due to high resistance to marine organisms such as barnacles, copper nickel is commonly used in seawater piping systems and oil piping systems.
Available Grades and Specifications
| Grade | UNS Number | Common Name |
|---|---|---|
| 90/10 Copper Nickel | C70600 / 7060X | CuNi 90/10, CuNi10Fe1.6Mn |
| 70/30 Copper Nickel | C71500 | CuNi 70/30 |
Pipe Size Chart
| Parameter | Range |
|---|---|
| Standard | ASME, API, ASTM |
| Specifications | DIN 86019, EEMUA 144, ASME B36.10 |
| Dimensions | ½ inch to 16 inch OD and NB in various thicknesses |
| Thickness | 1.5mm – 10mm / SCH5, SCH10, SCH40, STD, SCH80 |
| Length | 6 meters, Single Random, Double Random, or custom length |
| Type | Seamless or Welded |
| End Finish | Beveled End or Plain End |
International Standards Comparison
CuNi 90/10 (C70600 / 7060X) – Standard Specifications Comparison
| Element | DIN 86019 2.1972 | EEMUA 144 UNS 7060X | BS 2871 CN 102 | ASTM B466 C70600 | JIS H 3300 C7060 | MIL-T-16420K C70600 |
|---|---|---|---|---|---|---|
| Ni% | 9.0-11.0 | 10.0-11.0 | 10.0-11.0 | 9.0-11.0 | 9.0-11.0 | 9.0-11.0 |
| Fe% | 1.5-1.8 | 1.5-2.0 | 1.0-2.0 | 1.0-1.8 | 1.0-1.8 | 1.0-1.8 |
| Mn% | 0.5-1.0 | 0.5-1.0 | 0.5-1.0 | 1.0 Max. | 0.2-1.0 | 1.0 Max. |
| C% | 0.05 Max. | 0.05 Max. | - | 0.05 Max. | - | 0.05 Max. |
| Pb% | 0.03 Max. | 0.01 Max. | 0.01 Max. | 0.02 Max. | 0.05 Max. | 0.02 Max. |
| S% | 0.015 Max. | 0.02 Max. | - | 0.02 Max. | - | 0.02 Max. |
| P% | 0.02 Max. | 0.02 Max. | - | 0.02 Max. | - | - |
| Zn% | 0.15 Max. | 0.20 Max. | 0.50 Max. | 0.50 Max. | - | 0.05 Max. |
| Cu% | Balance | Balance | Balance | Balance | - | 86.5 Min. |
CuNi 70/30 (C71500) – Standard Specifications Comparison
| Element | DIN 17664 2.0882 | BS 2871 CN 107 | ASTM B466 C71500 | JIS H 3300 C7150 | NES 780 | MIL-T-16420K C71500 |
|---|---|---|---|---|---|---|
| Ni% | 30.0-32.0 | 30.0-32.0 | 29.0-33.0 | 29.0-33.0 | 30.0-32.0 | 29.0-33.0 |
| Fe% | 0.4-1.0 | 0.4-1.0 | 0.4-1.0 | 0.4-1.0 | 0.6-1.0 | 0.4-1.0 |
| Mn% | 0.5-1.5 | 0.5-1.5 | 1.0 Max. | 0.2-1.0 | 0.5-1.5 | 1.0 Max. |
| C% | 0.05 Max. | 0.06 Max. | 0.05 Max. | - | 0.06 Max. | 0.05 Max. |
| Pb% | 0.03 Max. | 0.01 Max. | 0.02 Max. | 0.05 Max. | 0.01 Max. | 0.02 Max. |
| S% | 0.02 Max. | 0.08 Max. | 0.02 Max. | - | 0.02 Max. | 0.02 Max. |
| P% | 0.02 Max. | - | 0.02 Max. | - | 0.01 Max. | - |
| Zn% | 0.5 Max. | 0.50 Max. | 0.50 Max. | - | 0.50 Max. | 0.50 Max. |
| Cu% | Balance | Balance | Balance | - | 66.5 Min. | 65.0 Min. |
Physical Properties
CuNi 90/10 (C70600)
| Property | Value |
|---|---|
| Tensile Strength (MPa) | 260 Min. |
| Yield Strength (MPa) | 90 Min. |
| Elongation (δ10%) | 30% Min. |
| Hardness (HV5) | 120 Max. |
CuNi 70/30 (C71500)
| Property | Value |
|---|---|
| Tensile Strength (MPa) | 360 Min. |
| Yield Strength (MPa) | 125 Min. |
| Elongation (δ10%) | 30% Min. |
Key Properties of Copper Nickel Pipes
| Property | Description |
|---|---|
| Corrosion Resistance | Low general corrosion rates in seawater (0.0025-0.025mm/yr) |
| Stress Corrosion Cracking | Highly resistant to ammonia-related stress corrosion |
| Crevice Corrosion | High resistance to crevice corrosion and chloride stress corrosion |
| Pitting Resistance | Good; pits tend to be broad and shallow |
| Biofouling Resistance | Inherent resistance due to copper ions at the surface |
| Weldability | Readily weldable; no post-weld heat treatment required |
| Fabrication | Easy to cold work and form |
Applications of Copper Nickel Pipes
| Industry | Application |
|---|---|
| Marine Engineering | Seawater piping systems, condensers, heat exchangers |
| Shipbuilding | Hulls, propellers, crankshafts, hydraulic lines |
| Desalination | Multi-stage flash desalination units |
| Petrochemical & Chemical | Corrosive fluid handling, heat exchangers |
| Armaments Industry | Military marine applications |
| Mint Industry | Coinage (typical mix: 75% copper, 25% nickel) |
| Offshore Oil & Gas | Fire water systems, platform leg sheathing, risers |
| Power Generation | Condenser tubes, cooling water systems |
Why Copper Nickel for Marine Applications?
Copper nickel is extremely resistant to corrosion in seawater because its electrode potential is neutral with respect to seawater. For this reason, copper nickel is used for heat exchangers, piping, and condensers in seawater systems.
Detection
| Inspection Method | Standard / Purpose |
|---|---|
| Eddy Current Testing | ASTM E243 - Detects defects in non-ferromagnetic tubing |
| Hydrostatic Test | Pressure integrity verification |
| Ultrasonic Testing | Wall thickness measurement |
| Chemical Analysis | Spectrometer - Verifies c71500 chemical composition or C70600 composition |
| Mechanical Testing | Tensile, hardness, flattening, expansion tests |
| Flattening Test | Required per ASTM B111 |
| Third-Party Inspection | SGS, BV, or as customer requested |
Packaging
| Item | Method |
|---|---|
| Small diameter pipes (≤ 12 inch) | Waterproof paper + plastic bag + wooden case |
| Large diameter pipes (> 12 inch) | Plastic end caps + steel strip bundles + wooden pallets |
| Marking | Grade (C70600/C71500), size, schedule, heat number, standard (ASTM B111 / ASME SB466) |
| Documents | Packing list, mill test certificate, commercial invoice |
Factory Equipment
| Equipment | Purpose for Copper Nickel Production |
|---|---|
| Induction Melting Furnace | Precise control of c71500 chemical composition and C70600 composition |
| Continuous Casting Machine | Billet production |
| Extrusion Press | Hollow shell formation |
| Cold Pilger Mill | Tube diameter reduction |
| Draw Bench | Final sizing and surface finish |
| Annealing Furnace | Stress relief (700-825°C for both alloys) |
| Straightening Machine | Dimensional accuracy |
| NDT Equipment | Eddy current and ultrasonic testing |
Certificates
