What's the difference between CuNi 90/10 and 70/30?

70/30, richer in nickel, has higher erosion-corrosion resistance for high flow velocities and warm seawater. 90/10 covers most everyday uses at a lower cost.

Are finned tubes available from partner stock?

No, mill route only — see the dedicated finned tubes page for detail on this sourcing route.

Where does this cluster's grade catalogue come from?

From the partner mill Metal Alloys Corporation's (India) public catalogue, verified on 15/08/2026: cupronickels, brasses, DHP/ETP coppers, bronzes, finned tubes and U-bend tubes.

Are these alloys used in naval and defence?

Yes, this is a legitimate use of cupronickels — condensers and seawater circuits on naval and defence applications.

COPPER ALLOYS

Copper alloys

Sheet, tube and bar in copper alloys for marine exchangers and condensers: cupronickel 90/10 and 70/30, admiralty/aluminium/naval brass, bronzes, DHP/ETP coppers. Finned tubes and tubesheets available from the mill.

Request a quote

What is a copper alloy for piping?

A copper alloy for piping is a material family — cupronickel, brass, bronze, pure copper — used in exchangers and condensers for its thermal conductivity and natural resistance to marine fouling, an alternative to stainless when the environment is particularly chloride-laden.

How to choose it?

Cupronickel 90/10 or 70/30 is the reference for a seawater condenser or exchanger. Admiralty or aluminium brass works in less severe environments; naval brass and bronzes cover mechanical and valve uses. See the cupronickel page for detail on the two reference grades.

In this pillar

Cupronickel tube Cupronickel 90/10 and 70/30 is the reference for marine condensers and exchangers: good th… Copper alloy finned tube A finned tube increases the air-side heat exchange surface of a bundle, in cupronickel or … Copper alloy tubesheet A tubesheet holds and positions the tubes of a condenser or exchanger bundle. Like finned …

Available grades

Cupronickel 90/10 (C70600) and 70/30 (C71500), cupronickel 95/5, admiralty brass (C44300), aluminium brass (C68700), naval brass (C46400), bronzes, DHP and ETP coppers — the partner mill Metal Alloys Corporation's catalogue, verified on 15/08/2026, covers this whole list.

Copper alloys (CuNi 90/10, CuNi 70/30, Laiton amirauté)

My grade isn't listed →

Applicable standards

ASTM B111 and ASME SB111 (exchanger tube), EN 12451, BS 2871 Part 3, JIS H3300 and NF A51-102 cover tube production. ASTM B466 was reviewed and excluded: absent from the partner mill catalogue, never verified.

ASTM B111
ASME SB111
EN 12451
BS 2871 Part 3
JIS H3300
NF A51-102

Partner stock or mill?

Standard forms (sheet, tube, bar) follow the same partner stock / mill logic as the rest of the site. Finned tubes and tubesheets, however, are only available from the mill — see their dedicated pages.

From partner stock: 48 hours for urgent needs, 5 working days as standard.

We go through the mill when volume and lead time make sense — typically container-load quantities, sometimes less, with a lead time of a few months including transport. That arbitration is ours to make: when buying at source works out cheaper for you, we say so.

Frequently asked questions

What's the difference between CuNi 90/10 and 70/30?: 70/30, richer in nickel, has higher erosion-corrosion resistance for high flow velocities and warm seawater. 90/10 covers most everyday uses at a lower cost.
Are finned tubes available from partner stock?: No, mill route only — see the dedicated finned tubes page for detail on this sourcing route.
Where does this cluster's grade catalogue come from?: From the partner mill Metal Alloys Corporation's (India) public catalogue, verified on 15/08/2026: cupronickels, brasses, DHP/ETP coppers, bronzes, finned tubes and U-bend tubes.
Are these alloys used in naval and defence?: Yes, this is a legitimate use of cupronickels — condensers and seawater circuits on naval and defence applications.

Piping doesn't stop at the tube