Copper Nickel Flange Manufacturer for 90/10 & 70/30 Alloys

Sunflex Metalloy manufactures copper nickel flanges for seawater, marine, offshore and industrial piping. Cu-Ni 90/10 and 70/30 flanges, standard and engineered, made to your ASME/ASTM project specification or drawing for buyers in the USA and worldwide.

Request a Quote Explore Flanges

Assortment of copper nickel flanges including weld neck, slip-on and blind types

Alloys: Cu-Ni 90/10 and 70/30
UNS designations: C70600 and C71500
Flange types: Twelve, plus custom to drawing
Established: 2010, three units in Gujarat

Copper nickel flanges, manufactured in India for the USA and international buyers

We are an India-based manufacturer and global supplier of copper nickel flanges. Our focus is narrow: Cu-Ni 90/10 and 70/30 flanges for piping that carries seawater and other chloride-bearing water.

Flanges are machined from copper-nickel stock to your drawing or to the dimensional standard in your specification. Material standards, dimensional standards and testing requirements are kept separate on every quotation, so what is ordered is what is supplied.

About Sunflex Metalloy

Copper nickel bar stock being cut to blank size on a saw — Bar stock cut to blank size

Machined copper nickel ring flange — Machined ring flange

Copper Nickel 90/10 and 70/30

Two alloys, one family. Both form a protective film in seawater. They differ in nickel content, strength, flow tolerance and cost.

Cu-Ni 90/10

UNS C70600

The alloy most often specified for seawater piping, cooling water, firewater and ballast systems. Economical, well proven, and available across all our flange types.

Copper Nickel 90/10 flanges

Cu-Ni 70/30

UNS C71500

Higher nickel content gives greater strength and better tolerance of flow velocity. Used for demanding duty, desalination and heat-exchanger systems.

Copper Nickel 70/30 flanges

Chemical composition and mechanical properties are governed by the applicable ASTM or ASME material specification for each order.

Copper nickel flange categories

Twelve flange types, each with its own page covering construction, standards references, sizes, facings and enquiry details.

Manufacturing capabilities

What we do in-house is limited to what we can describe accurately. Specific sizes, classes and tolerances are confirmed against your specification at quotation.

Material preparation

Copper-nickel bar and plate cut to blank size ahead of machining.

Machining

Outside diameter, bore, hub, facing and drilling machined to drawing or standard.

Custom drilling and bore

Non-standard bolt circles, tapped holes and special bores to your drawing.

Facings

Raised face, flat face and ring-type joint grooves, as your specification requires.

Marking and identification

Marking to your requirement, to support material traceability and identification.

Export packing

Packed for export shipment, including wooden crate packing.

Material expertise

Specifying copper nickel involves more than choosing 90/10 or 70/30. We help buyers state what the order depends on:

UNS designation and material specification, for example ASTM B151 or B122
Product form and the flange dimensional standard, for example ASME B16.5
Rating basis, which for copper nickel comes from the governing code and project specification
Galvanic isolation where copper-nickel meets steel
Documentation requirements, stated before manufacture

How to select the right copper nickel flange

Copper nickel weld neck flange with stamped identification — Identification marking on a weld neck flange

Applications

Copper-nickel flanges serve wherever seawater or chloride-bearing water flows through piping. Each application has its own section, with the reason copper-nickel is chosen.

Handheld analyzer used for material identification on copper nickel flanges — Material identification

Caliper measurement of a copper nickel flange — Dimensional checking

Quality and inspection

Inspection is organized around your purchase order. Visual, dimensional and material identification checks can be carried out, and documentation is arranged according to project requirements.

Material Test Certificate (MTC)
Dimensional inspection report
Certificate of conformity
PMI where applicable
Third-party inspection where requested

These are not issued automatically on every order, so list them in your enquiry. Quality and inspection

Technical advantages of copper nickel flanges

Why engineers specify copper-nickel for seawater piping, and what to keep in mind when they do.

Seawater film

A thin protective surface film forms in flowing, aerated seawater and slows further corrosion.

Chloride cracking

Not susceptible to chloride stress corrosion cracking.

Fouling behavior

Discourages marine growth on wetted surfaces, though stagnant conditions can still foul.

Weldable and machinable

Welded with matching filler metal under a qualified procedure, and machined to close tolerances.

One alloy through the line

Pipe, flanges and fittings in the same alloy keep corrosion behavior consistent.

Known limits

Velocity limits apply, and sulfide pollution, ammonia and oxidizing acids need review.

Custom copper nickel flange manufacturing

When a catalogue flange does not fit, we work from your drawing: custom dimensions, drilling, bore, facings and non-standard configurations, in 90/10 or 70/30.