Welded Copper Nickel Pipe
Welded copper-nickel pipe is produced from copper-nickel alloy strip or plate through forming and welding processes, followed by inspection, sizing and finishing.
HC supplies high-quality Welded Copper-Nickel Pipe for marine, offshore and industrial piping systems worldwide. Available in 90/10 Copper Nickel (UNS C70600) and 70/30 Copper Nickel (UNS C71500), our welded pipes combine outstanding seawater corrosion resistance with excellent fabrication performance and long service life.
Manufactured in accordance with international standards including ASTM, ASME, EEAMU, DIN, EN and MIL specifications, every pipe is inspected for dimensional accuracy, weld integrity and mechanical performance before shipment.
Welded Copper-Nickel Pipe Specifications
| Item | Specification |
| Product | Welded Copper-Nickel Pipe |
| Manufacturing Process | ERW (Electric Resistance Welded), Longitudinal Welded |
| Available Grades | C70600 (90/10 CuNi), C71500 (70/30 CuNi) |
| Product Type | Straight Pipe, Marine Pipe, Heat Exchanger Pipe |
| Outside Diameter (OD) | 15 mm – 1200 mm (1/2" – 48") |
| Wall Thickness (WT) | 1.0 mm – 25 mm |
| Length | Fixed Length, Random Length, Double Random, Customized Length |
| Pipe Standards | ASTM B466, ASTM B467, ASME SB466, ASME SB467, DIN 86019, DIN 86018, EEMUA 234, ASME B36.19M, EN, MIL Standards |
| Surface Finish | Pickled, Bright Annealed (BA), Polished |
| Testing & Inspection | Hydrostatic Test, Eddy Current Test, PMI, Ultrasonic Test (UT), Mechanical Test, Dimensional Inspection, Visual Inspection |
| Applications | Shipbuilding, Offshore Platforms, Seawater Cooling Systems, Desalination Plants, Heat Exchangers, Condensers, Power Plants, Marine Engineering |
| Supply Condition | Annealed, Straight Ends, Plain Ends, Beveled Ends |
| OEM Service | Custom Sizes, Custom Lengths, Marking, Packaging Available |
Welded Copper-Nickel Pipe for Marine, Offshore & Seawater Systems
The most common grades are C70600 / CuNi 90/10 and C71500 / CuNi 70/30. Both grades are widely used in marine and industrial seawater systems, while the final selection usually depends on flow velocity, corrosion conditions, project standards and service environment.
If you are comparing different alloy options, you can also visit our Copper Nickel Pipe page for a broader material overview.
C70600 / CuNi 90/10 Welded Copper-Nickel Pipe
Widely used for seawater pipelines, shipbuilding, condensers and cooling systems. It offers a practical balance of corrosion resistance, workability and long-term cost performance.
For projects focused on seawater service, our CuNi 90/10 Pipe is one of the most commonly selected solutions.
C71500 / CuNi 70/30 Welded Copper-Nickel Pipe
Preferred for higher flow velocity, stronger corrosion resistance and more demanding offshore conditions. It is commonly used in severe marine and offshore applications.
For high-performance offshore applications, you may also check our CuNi 70/30 Pipe product page.
Why Choose Welded Copper-Nickel Pipe?
Welded copper-nickel pipe is selected not only for corrosion resistance, but also for its practical advantages in fabrication, installation and long-term maintenance.
Compared with carbon steel and stainless steel, welded copper-nickel pipe offers significantly better resistance to seawater corrosion, biofouling and chloride attack. The smooth internal surface reduces pressure loss while minimizing marine organism attachment, making it the preferred material for seawater transportation systems.
Excellent Resistance to Seawater Corrosion
Copper-nickel alloys form a protective surface film in seawater, helping the pipe resist general corrosion, pitting and stress corrosion cracking.
This makes welded copper-nickel pipe a practical option for:
- Seawater intake and discharge lines
- Firewater systems
- Ballast systems
- Offshore cooling water pipelines
- Desalination and brine pipelines
For projects focused on seawater service, our CuNi 90/10 Pipe is one of the most commonly selected solutions.
Good Biofouling Resistance
Marine growth can reduce flow efficiency and increase maintenance costs. Copper-nickel pipe naturally helps reduce biofouling compared with many conventional piping materials.
This advantage is one reason engineers often choose copper-nickel for Marine Piping Systems.
Strong Weldability and Fabrication Performance
Welded copper-nickel pipe offers good fabrication performance and can be supplied in different sizes, wall thicknesses and lengths. It is suitable for further processing such as cutting, bending, flange connection and on-site installation.
For larger or more complex systems, we can also supply matching Copper Nickel Pipe Fittings, including elbows, tees, reducers and flanges.
Long Service Life with Lower Maintenance Costs
Although the initial material cost may be higher than some alternatives, copper-nickel pipe often provides a lower total cost over the service life of the system.
Its resistance to seawater corrosion and marine fouling helps reduce shutdowns, replacement frequency and maintenance workload. For offshore and shipbuilding projects, this long-term reliability is especially valuable.
Welded Copper Nickel Pipe Common Standards
Our welded copper-nickel pipes are manufactured in accordance with internationally recognized specifications to meet the requirements of marine, offshore, shipbuilding, power generation, and industrial piping projects. In addition to standard production, we also support project-specific technical specifications and customer engineering drawings.
International Standards
- ASTM B466 / ASTM B467
- ASME SB466 / ASME SB467
- ASTM B543
- DIN 86018 / DIN 86019
- EN Standards
- MIL Specifications
Marine & Offshore Specifications
- EEMUA 144
- EEMUA 234
- ASME B36.19M
- Shipbuilding Project Standards
- Offshore Engineering Requirements
Custom Manufacturing
- Project Technical Specifications
- Client Drawings & Dimensions
- Special Mechanical Property Requirements
- Customized Inspection & Testing Plans
- Third-Party Certification Available
Whether you require ASTM-standard welded CuNi pipe for commercial applications or project-specific products manufactured to customer specifications, our engineering team can provide compliant solutions with complete material traceability and inspection documentation.
Welded Copper Nickel Pipe Stock
CuNi Pipe Stock — DIN 86019 / DIN 86018
| Seam-welded Pipe | |||
| 18 | 450 | 457 | 4.5 |
| 20 | 500 | 508 | 5 |
| 24 | 600 | 610 | 5 |
| 28 | 700 | 711 | 6 |
| 32 | 800 | 813 | 6 |
| 36 | 900 | 914 | 8 |
CuNi Pipe Stock — EEMUA 234
| Seam-welded Pipe | ||||
| 18 | 450 | 457.2 | 8 | 9.5 |
| 20 | 500 | 508 | 8.5 | 11 |
| 24 | 600 | 610 | 10.5 | 13 |
| 28 | 700 | 711 | 12 | 15 |
| 32 | 800 | 813 | 13.5 | 17 |
| 36 | 900 | 914 | 15.5 | 19 |
CuNi Pipe Stock — ASME B36.19M
| Seam-welded Pipe | |||
| 18 | 450 | 457 | 4.78 |
| 20 | 500 | 508 | 5.54 |
| 24 | 600 | 610 | 6.35 |
Copper Nickel Material Grades
Our welded copper nickel pipes are manufactured in the two most widely specified copper nickel alloys for marine and industrial service: UNS C70600 (90/10 CuNi) and UNS C71500 (70/30 CuNi). Each grade offers excellent resistance to seawater corrosion while providing different mechanical properties for specific operating conditions.
If you are selecting materials for shipbuilding, offshore platforms, condensers, or seawater piping systems, our engineering team can help verify the appropriate alloy according to your project specifications and applicable standards.
| UNS Grade | Alloy | Recommended Applications |
| C70600 | 90/10 Copper Nickel | Marine piping, condensers, cooling water systems, shipbuilding and desalination plants |
| C71500 | 70/30 Copper Nickel | Offshore facilities, high-velocity seawater pipelines, naval vessels and demanding marine environments |
Projects operating under higher seawater velocity or more aggressive corrosion conditions often specify 70/30 Copper Nickel Pipe for its improved strength and enhanced resistance to erosion-corrosion.
Applications of Welded Copper-Nickel Pipe
Welded copper-nickel pipe is widely used in industries where corrosion resistance and stable service life matter.
Typical applications include:
- Shipbuilding
- Naval vessels
- Offshore platforms
- Seawater cooling systems
- Desalination plants
- Heat exchangers
- Power stations
- Fire protection piping
- Marine condensers
- Chemical processing plants
- Oil & gas facilities
- Industrial cooling water systems
If your project involves seawater handling or coastal operation, copper-nickel pipe can provide a dependable balance of durability, workability and long-term value.
Welded Copper Nickel Pipe Chemical Composition
90/10 (UNS C70600) Welded CuNi Pipe Chemical Composition
| KME CuNi90/10 | DIN 17664 2.0882 | BS 2871 CN102 | ASTM B466 C70600 | JIS H3300 C7060T | DIN 86019 2.1972 | EEMUA 234 UNS 7060X | GB/T 5231 BFe10-1.6-1 | |
| Ni% | 10.0-11.0 | 9.0-11.0 | 10.0-11.0 | 9.0-11.0 | 9.0-11.0 | 9.0-11.0 | 10.0-11.0 | 9.0-11.0 |
| Fe% | 1.5-1.8 | 1.0-2.0 | 1.0-2.0 | 1.0-1.8 | 1.0-1.8 | 1.5-1.8 | 1.5-2.0 | 1.5-1.8 |
| Mn% | 0.6-1.0 | 0.5-1.0 | 0.5-1.0 | max.1.0 | 0.2-1.0 | 0.5-1.0 | 0.5-1.0 | 0.5-1.0 |
| C% | max.0.05 | max.0.05 | max.0.05 | max.0.05 | max.0.05 | max.0.05 | max.0.05 | |
| Pb% | max.0.01 | max.0.03 | max.0.01 | max.0.02 | max.0.05 | max.0.01 | max.0.01 | max.0.03 |
| S% | max.0.005 | max.0.02 | max.0.05 | max.0.02 | max.0.005 | max.0.02 | max.0.01 | |
| P% | max.0.02 | max.0.02 | max.0.02 | max.0.02 | max.0.02 | max.0.02 | ||
| Zn% | max.0.05 | max.0.50 | max.0.50 | max.0.50 | max.0.05 | max.0.20 | max.0.20 | |
| Other | max.0.20 | max.0.30 | max.0.20 | max.0.30 | max.0.40 | |||
| Cu% | rem. | rem. | rem. | rem. | +Ni+Fe+Mn min99.5 | rem. | rem. | rem. |
70/30 (UNS C71500) Welded CuNi Pipe Chemical Composition
| KME CuNi70/30 | DIN 176642.0882 | BS 2871 CN107 | ASTM B466C71500 | JIS H3300C7150T | |
| Ni% | 30.0-32.0 | 30.0-32.0 | 30.0-32.0 | 29.0-33.0 | 29.0-33.0 |
| Fe% | 0.47-0.7 | 0.4-1.0 | 0.4-1.0 | 0.4-1.0 | 0.4-1.0 |
| Mn% | 0.5-1.0 | 0.5-1.5 | 0.5-1.5 | max.1.0 | 0.2-1.0 |
| C% | max.0.04 | max.0.05 | max.0.06 | max.0.05 | |
| Pb% | max.0.01 | max.0.03 | max.0.01 | max.0.02 | max.0.05 |
| S% | max.0.01 | max.0.02 | max.0.08 | max.0.02 | |
| P% | max.0.02 | max.0.02 | max.0.02 | ||
| Zn% | max.0.20 | max.0.50 | max.0.50 | max.0.50 | |
| Other | max.0.30 | max.0.30 | |||
| Cu% | rem. | rem. | rem. | rem. | +Ni+Fe+Mn min99.5 |
Quality Control for Copper Nickel Welded Pipes
Each copper nickel welded pipe is produced under a controlled inspection process to help ensure stable corrosion resistance, reliable weld integrity and accurate dimensions for marine, offshore and shipbuilding applications. From incoming material verification to final pressure testing, every key production stage is checked to meet project specifications and international standards.
- Incoming raw material verification with mill certificate review
- Positive Material Identification, including Cu-Ni grade confirmation
- Weld seam inspection for consistency and structural reliability
- Hydrostatic pressure testing before shipment
- Eddy current testing for surface and near-surface discontinuities
- Ultrasonic examination when required by project standards
- Dimensional inspection for outside diameter, wall thickness and length
- Mechanical testing to verify strength, elongation and performance
- Independent third-party inspection available upon request
Our Supply Capability for Welded Copper-Nickel Pipe
Every welded copper-nickel pipe project has different technical requirements. We manufacture products according to your drawings, specifications, and international standards to support marine, offshore, and industrial applications.
Our production capabilities allow us to deliver both standard products and custom solutions with reliable quality and consistent lead times.
- Custom outside diameter, wall thickness, and pipe length
- Single random, double random, or fixed-length production
- Plain end, beveled end, or machining based on project requirements
- Internal and external surface cleaning before shipment
- Hydrostatic testing, PMI verification, dimensional inspection, and visual examination
- EN 10204 3.1 material certificates and complete inspection documentation
- Export-grade packaging for sea freight, container loading, and long-distance transportation
Our quality management process covers raw material verification, in-process inspection, final testing, and packaging inspection before delivery.
Why Choose Our Welded Copper Nickel Pipe?
For marine, offshore and industrial piping systems, a dependable copper nickel pipe supplier should offer more than a competitive price. Consistent material quality, clear traceability, responsive communication and on-time delivery are all essential to keeping your project moving.
Technical Guidance From Inquiry to Delivery
Our team supports buyers, engineers and procurement teams throughout the purchasing process, helping reduce specification errors and sourcing delays.
- Assistance with CuNi 90/10 and CuNi 70/30 material selection
- Review of ASTM, ASME, EN, DIN and project-specific requirements
- Coordination of pipes with compatible fittings, flanges and accessories
- Material certificates, packing lists and export documents preparation
- Order planning for maintenance, repair and project-based procurement
Stable Supply for Marine and Industrial Applications
Our welded copper nickel pipes are supplied for seawater cooling systems, shipbuilding, desalination plants, offshore facilities and other corrosive service environments. Each order can be arranged according to project drawings, applicable standards and delivery schedules.
To simplify procurement, we can also provide matching copper nickel pipe fittings for complete piping system requirements.
Packaging & Delivery
Each welded copper-nickel pipe is carefully prepared for shipment to help protect the surface, pipe ends and overall dimensional integrity during handling, storage and long-distance transport. Depending on pipe size, order quantity and destination requirements, we provide seaworthy wooden cases, plywood crates, steel-framed bundles or customized export packaging.
Pipe ends can be fitted with protective caps, and moisture-resistant wrapping, inner supports and secure strapping are used when required to reduce the risk of scratches, dents, contamination or movement in transit. Clear product labels, heat numbers, specifications, quantities and customer-required shipping marks can be added for easy identification and warehouse management.
We also support tailored packing solutions for project cargo, container loading and international delivery, helping ensure welded copper-nickel pipes arrive safely and ready for inspection or installation.
Frequently Asked Questions – Welded Copper-Nickel Pipe
What is a welded copper-nickel pipe?
A welded copper-nickel pipe is manufactured by forming a copper-nickel strip into a cylindrical shape and joining the edges using a longitudinal welding process. It provides excellent seawater corrosion resistance while offering a cost-effective solution for medium and large diameter piping systems.
Is welded copper-nickel pipe suitable for seawater?
Yes. Both C70600 and C71500 welded copper-nickel pipes are specifically developed for seawater service and exhibit excellent resistance to chloride corrosion, biofouling, and erosion.
What is the difference between seamless and welded copper-nickel pipe?
Seamless pipe is manufactured without a weld seam and is commonly selected for high-pressure applications. Welded copper-nickel pipe is more economical for larger diameters while still providing excellent corrosion resistance and mechanical reliability for most marine and industrial systems.
Which grade is better, C70600 or C71500?
C70600 (90/10) is widely used in commercial marine systems due to its excellent balance of corrosion resistance and cost. C71500 (70/30) offers higher strength and improved resistance in high-velocity seawater or more aggressive marine environments.
Can you manufacture custom sizes?
Yes. HC manufactures welded copper-nickel pipes in customized diameters, wall thicknesses, lengths, and specifications according to project requirements.
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