Copper Nickel
Cupro nickel 90/10 (C70600) and 70/30 (C71500) tube, pipe, plate, sheet, bar, flange and fitting — ASTM B111 / B466 / B171 with EN 10204 3.1 / 3.2 MTC.
What is cupro nickel?
Cupro nickel is a copper-nickel alloy — 90/10 (UNS C70600, 10% Ni) and 70/30 (UNS C71500, 30% Ni) — with excellent resistance to seawater corrosion, erosion and biofouling, making it the default material for marine condenser tubing, seawater piping and offshore firewater systems. The 70/30 grade tolerates higher flow velocities and temperatures than 90/10.
Steelco Metal & Alloys stocks cupro nickel in Mumbai in condenser and heat-exchanger tube, seamless and welded pipe, plate, sheet, bar, forged flanges and buttweld fittings, sourced from approved European, Japanese and Indian producers. Every dispatch leaves our Mumbai warehouse with an EN 10204 3.1 mill test certificate (3.2 with TUV, SGS, BV, Lloyd's or IRS witness on request), PMI verification and full heat-number traceability.
Cupro nickel grades we stock.
Both marine grades are held in ready stock, with tube sheets and fittings to match.
Cupro Nickel we hold in ready stock.
Condenser tube
Ø 6 – 76 mm to ASTM B111 in 90/10 and 70/30, straight and U-bent.
Pipe
Seamless and welded 1/2" – 24" NB to ASTM B466 / B467.
Plate & sheet
1 – 50 mm to ASTM B171 / B122 for tube sheets and vessels.
Round bar
Ø 6 – 200 mm to ASTM B151 for machined components.
Flanges
Forged flanges 1/2" – 24", Class 150 – 300 to ASTM B171 / MSS SP-44.
Fittings
Buttweld and forged fittings to ASME B16.9 / B16.11 in C70600 and C71500.
Use our free metal weight calculator — bars, sheets, plates, pipes and sections.
Our cupro nickel range
Ready stock across every mainstream form — dispatched with mill test certificates and full traceability from our Mumbai warehouse.
Condenser Tube
Ø 6 – 76 mm, ASTM B111, straight and U-bent.
Explore
Pipe & Fittings
Seamless and welded 1/2" – 24" NB.
Explore
Plate & Sheet
1 – 50 mm for tube sheets and vessels.
Explore
Round Bar
Ø 6 – 200 mm for machined parts.
Explore
Flanges
Class 150 – 300 forged flanges.
Explore
Tube Sheets
Drilled and grooved to drawing.
Explore
Fasteners
Marine-grade studs, bolts and nuts.
Explore
Welding Consumables
ERCuNi filler wire and ECuNi electrodes.
ExploreCupro Nickel specifications.
Standards, sizes, thickness and condition we routinely supply across every product form.
| Product | Size Range | Thickness / Wall | Finish / Condition | Standards |
|---|---|---|---|---|
Condenser Tube | Ø 6 – 76 mm | 0.7 – 3 mm | Annealed, light drawn | ASTM B111 / B543 |
Seamless Pipe | 1/2" – 12" NB | Sch 10 – Sch 80 | Annealed | ASTM B466 |
Welded Pipe | 1/2" – 24" NB | Sch 5 – Sch 40 | Annealed | ASTM B467 |
Plate & Sheet | 1000 – 2000 mm wide | 1 – 50 mm | Hot- and cold-rolled | ASTM B171 / B122 |
Round Bar | Ø 6 – 200 mm | — | Drawn, extruded | ASTM B151 / B21 |
Flanges | 1/2" – 24" | Class 150 – 300 | Forged, machined | ASTM B171 / MSS SP-44 |
Note: Eddy-current tested tube and hydro-tested pipe available on request.
Where cupro nickel is used.
Shipbuilding
Seawater cooling, ballast, bilge and firewater piping in 90/10.
Power Plants
Surface condenser and auxiliary cooler tubing in 70/30.
Desalination
Brine heater and heat recovery tubing resistant to erosion-corrosion.
Offshore Platforms
Firewater ring mains, seawater lift and splash-zone piping.
Oil & Gas
Coolers, condensers and utility seawater systems.
Marine Fabrication
Tube sheets, baffles and heat-exchanger internals.
Frequently asked questions.
Answers to the questions our Mumbai desk is asked most often.
What is the difference between cupro nickel 90/10 and 70/30?
+
90/10 (C70600) contains about 10% nickel and is the economical choice for seawater piping at flow velocities up to roughly 3.5 m/s. 70/30 (C71500) contains about 30% nickel with higher strength, better resistance to erosion at velocities up to about 4.5 m/s, and better performance in polluted or higher-temperature seawater.
Why is cupro nickel used for seawater systems?
+
Copper-nickel forms a protective cuprous oxide film in seawater and the copper content is naturally biofouling-resistant, so marine growth does not colonise the surface. This combination of corrosion resistance and antifouling behaviour keeps heat-transfer performance stable over decades of condenser service.
What welding consumable is used for cupro nickel?
+
ERCuNi (AWS A5.7) filler wire for GTAW and GMAW, and ECuNi (AWS A5.6) covered electrodes for manual welding. Both are 70/30 based even when joining 90/10, so that the weld metal is more corrosion resistant than the parent metal.
Every dispatch is traceable, tested and certified.
Material is supplied with EN 10204 3.1 (3.2 on request) mill test certificates, PMI and spectro verification, and is open to third-party inspection by TUV, SGS, BV, Lloyd’s and IRS from our Mumbai warehouse.
EN 10204 3.1 / 3.2
Mill test certificate with every consignment.
PMI & Spectro
Positive material identification before dispatch.
Third-party Inspection
TUV · SGS · BV · Lloyd's · IRS welcome.
Export Documentation
Full set prepared for 40+ countries.
Other grades you may also need
Ready to price your requirement?
Share your grade, form, size and quantity — our Mumbai desk responds with pricing, stock position and lead time, usually the same working day.