Home > Welded Tubes > Copper Brass Copper Nickel Welded Tubes
INOX STEEL INDIA is a trusted supplier of Copper, Brass and Copper-Nickel (Cu-Ni) Welded Tubes, engineered for marine service, desalination, HVAC, offshore platforms, heat exchangers, and power plant cooling systems.
Cu-Ni alloys — especially 90/10 and 70/30 — are world-standard materials used for seawater cooling, condensers, heat exchangers, brine systems and marine hardware due to their:
All tubes are produced as per ASTM B466 / B467, TIG-welded, bead-controlled, pickled, and tested for dimensional accuracy & corrosion performance.
Copper-Nickel welded tubes are fabricated from copper-nickel alloy strip/plate, precision-formed into tubes and welded using TIG or Plasma welding. These alloys deliver:
Cu-Ni 90/10 (C70600)
90% Copper + 10% Nickel (with Fe & Mn)
Perfect for:
Shipbuilding
Seawater pipelines
Firewater systems
Heat exchangers
Cu-Ni 70/30 (C71500)
70% Copper + 30% Nickel
Perfect for:
Offshore platforms
Subsea piping
Desalination plant evaporators
High-chloride brine heaters
Copper-Nickel welded tubes are fabricated from copper-nickel alloy strip/plate, precision-formed into tubes and welded using TIG or Plasma welding.
Marine & Shipbuilding
Desalination Plants
HVAC & Refrigeration
| Parameter | Cu-Ni 90/10 | Cu-Ni 70/30 |
|---|---|---|
| Seawater Corrosion | ⭐⭐⭐⭐ | ⭐⭐⭐⭐⭐ |
| Erosion Resistance | ⭐⭐⭐⭐ | ⭐⭐⭐⭐⭐ |
| Thermal Conductivity | ⭐⭐⭐⭐⭐ | ⭐⭐⭐⭐ |
| Cost | Lower | Higher |
| Typical Use | General marine | High-velocity seawater, offshore |
| Outside Diameter (OD) | Wall Thickness (WT) | Typical Applications |
|---|---|---|
| 6 – 12.7 mm | 0.7 – 1.2 mm | HVAC coils, chiller lines, refrigeration |
| 12.7 – 25.4 mm | 0.7 – 2.0 mm | Marine cooling lines, condensers |
| 25.4 – 50.8 mm | 1.0 – 3.0 mm | Heat exchangers, oil & gas seawater piping |
| 50.8 – 108 mm | 1.2 – 5.0 mm | Desalination, offshore firewater systems |
| 108 – 219 mm | 1.5 – 8.0 mm | High-capacity seawater intake & brine systems |
Available Lengths: ✔ 1m • 3m • 6m • 12m | ✔ Custom cut lengths for heat exchanger bundles.
| Corrosive Environment | Cu-Ni 90/10 | Cu-Ni 70/30 | Brass | Copper |
|---|---|---|---|---|
| Seawater | ⭐⭐⭐⭐ | ⭐⭐⭐⭐⭐ | ⭐⭐ | ⭐ |
| High-velocity seawater (>3 m/s) | ⭐⭐ | ⭐⭐⭐⭐⭐ | ⭐ | ⭐ |
| Brine systems | ⭐⭐⭐ | ⭐⭐⭐⭐ | ⭐ | ⭐ |
| Biofouling resistance | ⭐⭐⭐⭐ | ⭐⭐⭐⭐⭐ | ⭐⭐ | ⭐ |
| Material | Thermal Conductivity (W/m·K) | Heat Transfer Suitability |
|---|---|---|
| Copper | 380–400 | Excellent, highest heat transfer |
| Cu-Ni 90/10 | 40–60 | Good, stable in seawater |
| Cu-Ni 70/30 | 25–40 | Moderate, but superior corrosion resistance |
| Brass | 105–120 | Very good for HVAC |
Welding Processes Used: TIG / GTAW, Plasma Welding, Automatic Welding.
| Alloy | Filler Metal | AWS Code | Notes |
|---|---|---|---|
| Cu-Ni 90/10 | ERCuNi | AWS A5.7 | Matches 90/10 chemistry |
| Cu-Ni 70/30 | ERCuNi70/30 | AWS A5.7 | Higher Ni for seawater velocity |
| Copper | ERCu | — | High conductivity joints |
| Brass | ERCuZn | — | Requires skilled welding for Zn control |
| Application Requirement | Recommended Alloy | Reason |
|---|---|---|
| General seawater systems | Cu-Ni 90/10 | Balanced cost + corrosion |
| High-velocity seawater | Cu-Ni 70/30 | Highest erosion resistance |
| Desalination | C71500 (70/30) | Handles hot brine + chlorides |
| HVAC & refrigeration | Brass / Copper | High thermal conductivity |
Standard Tests (ASTM B466/B467)
✔ Hydrostatic Test
✔ Eddy Current Test
✔ Visual & Dimensional
✔ Mechanical Tests (TS/YS/Elongation)
Optional Tests
✔ PMI (Positive Material Identification)
✔ IGC (Intergranular Corrosion)
✔ Ultrasonic Testing
✔ Radiography (RT)
✔ Flattening / Flaring
✔ Erichsen Cupping Test (for ductility)
Certifications Available
| Alloy | Welded Tube Price (INR/Kg) | Welded Tube Price (USD/Kg) |
|---|---|---|
| Cu-Ni 90/10 (C70600) | ₹ 950 – ₹ 1,450 | $12 – $18 |
| Cu-Ni 70/30 (C71500) | ₹ 1,350 – ₹ 1,950 | $17 – $24 |
| Brass Tubes | ₹ 600 – ₹ 900 | $7 – $12 |
| Copper Tubes | ₹ 700 – ₹ 1,200 | $8 – $15 |
Prices vary based on OD, WT, welding method, testing level & export requirements.
| Finish | Usage |
|---|---|
| Bright Annealed | HVAC, refrigeration |
| Pickled & Passivated | Marine & seawater |
| Light Polished | Architectural |
| Cleaned & Degreased | Heat exchangers, offshore |
Stock Locations: Mumbai • Ahmedabad • Chennai • Pune • Hyderabad • Delhi NCR • Bengaluru.
Export Supply: Marine-grade export supply to GCC, Europe & Asia. All shipments certified, tested & seaworthy.
| Industry | Why Cu-Ni/Brass/Copper is Preferred | Grade Recommendation |
|---|---|---|
| Marine & Shipbuilding | Anti-biofouling, seawater stability | Cu-Ni 90/10 |
| Offshore Oil & Gas | High-strength + corrosion resistance | Cu-Ni 70/30 |
| Desalination | Handles hot brine & high chlorides | Cu-Ni 70/30 |
| HVAC & Refrigeration | High thermal conductivity | Copper/Brass |
| Power Plants | Efficient heat transfer in condensers | Cu-Ni 90/10 |
| Chemical Processing | Stable in aggressive water chemistries | Cu-Ni 70/30 |
✔ Standard Packaging
✔ Export Packaging
✔ Documentation
For Copper-Nickel, Brass & Copper Welded Tubes,
52-A, Mulji Thackersi Bldg, Islampura Street, Shop No. 10, Near Alankar Cinema, Mumbai – 400 004
alloy@inoxsteelindia.in
+91 9930796690
For seawater cooling, condensers, desalination, offshore platforms, HVAC & marine pipelines. 90/10 → General seawater 70/30 → High-velocity, aggressive seawater Yes — Cu-Ni alloys naturally prevent algae, mussel & barnacle growth. Yes — fully compliant with hydro, eddy current & PMI reports. TIG/Plasma welding for strong, clean joints. Yes — they offer excellent heat transfer + corrosion stability. Yes — INOX STEEL INDIA exports to UAE, Saudi Arabia, Oman, Qatar, Europe & Africa. What are Cu-Ni 90/10 and 70/30 welded tubes used for?
Which alloy is better for seawater?
Do copper-nickel tubes resist biofouling?
Do you supply ASTM B466 / B467 tubes?
What welding process is used?
Are copper-nickel tubes suitable for heat exchangers?
Do you export to GCC & Europe?
Manufacturer & supplier of Copper-Nickel Welded Tubes in Cu-Ni 90/10 (C70600) and 70/30 (C71500). TIG/Plasma welded, seawater corrosion-resistant tubes for marine, offshore, desalination, HVAC & heat exchangers. ASTM B466/B467 certified. Exporter to GCC, Europe & Asia.
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