What C70600 is
C70600 is nominally 90% copper, 10% nickel, with iron and manganese additions that build a tough, self-healing oxide film in flowing seawater. That film is why 90/10 copper-nickel resists erosion-corrosion, pitting, and biofouling far better than brass, and why it has been the standard for shipboard seawater systems and coastal power station condensers for seventy years.
It also transfers heat well, forms and welds easily, and is one of the few alloys that gets more reliable the longer it sits in salt water.
Processed in Hillsboro, not imported and relabeled
Ameritube has manufactured copper-nickel tube for two decades. Qualified cast shells come in, and everything after that happens in one building in Texas: pilgering, multi-pass drawing, annealing in our 60-foot furnace, straightening, cutting, cleaning, and 100% testing. Every step is on the same traveler, and the mechanical properties on your MTR were produced here. Ameritube now melts and casts C12200 copper in-house, and copper-nickel is next in line for the furnace.
That matters for three reasons:
- Documented origin. Country of origin and processing history stated on every certification, so your DFARS and Buy American review has what it needs.
- Lead time you can plan around. Shells are stocked; finished tube is made to your order here, not on a foreign mill's schedule.
- Accountability. If a question comes up about a test result, the person who ran the draw bench is down the hall.
Standards we supply to
- ASME SB-111 / ASTM B111, condenser and heat exchanger tube
- ASME SB-466 / ASTM B466, seamless pipe and tube for general service
- MIL-T-16420K, Class 200, 700, 1650, 3300, and 6000, shipboard seawater piping
- MIL-T-15005F, condenser and heat exchanger tube for naval service
- ASTM B543 and B552 equivalents on request
Chemical composition
| Element | Requirement |
|---|---|
| Copper | Remainder (nominal 88.6 to 90.4%) |
| Nickel | 9.0 to 11.0% |
| Iron | 1.0 to 1.8% |
| Manganese | 1.0% max |
| Zinc | 1.0% max |
| Lead | 0.05% max |
Typical mechanical properties, annealed
| Property | Value |
|---|---|
| Tensile strength | 40,000 psi min (275 MPa) |
| Yield strength | 15,000 psi min (105 MPa) |
| Elongation in 2" | 30% min |
| Density | 0.323 lb/in3 (8.94 g/cm3) |
Where it is used
- Marine and naval. Seawater cooling, firemain, ballast, and bilge piping. Condenser tube for surface ships and submarines. Complete ship sets with fittings and flanges, see the marine page.
- Heat exchangers and condensers. Coastal and estuary power stations, refinery cooling water exchangers, compressor skid coolers on offshore platforms.
- Desalination. Multi-stage flash and multi-effect distillation evaporator and heat recovery tube.
- Chemical process. Gulf Coast plants running brackish cooling water, where admiralty brass has failed.
- Offshore oil and gas. Seawater lift, cooling, and fire water systems on platforms and FPSOs.
When to step up to C71500
If water velocity exceeds about 10 feet per second, if the water is polluted with sulfides, or if the design calls for higher strength, 70/30 copper-nickel (C71500) is the next alloy up. We make both. Ask and we will tell you which one the service actually needs.
Tube or pipe, OD and wall (or NPS and schedule), temper, length, quantity, the governing spec and class (for MIL-T-16420K state Class 200 through 6000), any bending or U-bend requirement, and the level of NDT and certification your customer needs.