Cupro Nickel Flanges | UNS C70600 | UNS C71500

PM Industries manufactures, supplies, and stocks Cupro-Nickel alloy products across a range of forms, compositions, and sizes. Cupro-nickel is a copper-nickel alloy family, with the two most widely used compositions being 90/10 (90% copper, 10% nickel, UNS C70600) and 70/30 (70% copper, 30% nickel, UNS C71500), along with small additions of iron and manganese that improve resistance to flow-induced corrosion and erosion. The nickel content is what lifts the alloy above standard copper in corrosion performance, adding resistance to biofouling, stress corrosion cracking, and pitting in chloride-rich environments that copper alone doesn't provide.

The protective mechanism that makes cupro-nickel effective in marine service is the formation of a stable, adherent nickel-enriched oxide layer on the surface in seawater exposure. That layer develops over time and slows further corrosion attack, which is why cupro-nickel systems often show decreasing corrosion rates after initial exposure rather than progressive attack. In flowing seawater systems, that protective layer holds up well at normal flow velocities, making the alloy reliable for piping, tubing, and heat exchanger applications where standard stainless grades or carbon steel would corrode unacceptably.

Seawater heat exchanger and condenser tube applications are the most consistently specified use for cupro-nickel globally. In power plant condensers, marine vessel heat exchangers, and desalination plant heat recovery equipment, seawater is the cooling medium and the tube material must resist both general and localized corrosion in that environment over decades of service. Cupro-nickel, particularly 70/30 in the most demanding service, provides the corrosion life and biofouling resistance that makes it the standard specification in those systems. Titanium is sometimes preferred for the highest-performance or highest-flow conditions, but cupro-nickel remains the cost-effective standard for the broad middle range of seawater heat exchanger service.

Biofouling resistance is a practical operating advantage beyond simple corrosion resistance. Marine organisms, including barnacles, mussels, and algae, accumulate on submerged surfaces and reduce heat transfer efficiency and flow capacity in piping and heat exchangers. Cupro-nickel's surface chemistry inhibits that biological growth more effectively than most competing materials, reducing the frequency and cost of mechanical cleaning and biocide treatment in marine systems.

90/10 versus 70/30 selection is driven by the severity of the service environment. The 90/10 alloy handles the majority of marine and industrial applications at lower cost. The 70/30 alloy provides better performance in higher-temperature seawater, higher-velocity conditions, and more corrosive media where 90/10 shows accelerated attack. For critical piping and heat exchanger applications in offshore and naval service, 70/30 is frequently the specification.

Non-magnetic properties make cupro-nickel useful in specific instrumentation, sonar, and naval applications where magnetic interference must be minimized. Combined with seawater corrosion resistance, that non-magnetic behavior makes it practical for sonar dome hardware and underwater sensor housings in naval applications.

Cupro-nickel products are available in tube, pipe, sheet, plate, bar, and fitting forms across C70600 and C71500 compositions with full material certification to ASTM B111, B122, B171, and applicable standards. Contact PM Industries for product form, composition, dimensions, and pricing.

Specification Cupro Nickel Flanges

Standards	ANSI/ASME B16.5, B16.48, ANSI Flanges, GOST Flanges, DIN Flanges, EN-1092, B16.47 Series A & B, ASME Flanges, EN Flanges, AWWA Flanges, BS Flanges.
JIS Standard	5K, 10 K, 16 K 20 K, 30 K, 40 K, 63 K
DIN FLANGES	DIN 2527, 2627, 2631, 2656, 2576, 2673, 2629, 2628, 2566, 2641, 2637, 2655, 2634, 2636, 2632, 2633, 2638, 2642, 2573, 2635.
Pressure Rating	Class 150 LBS, 300 LBS, 600 LBS, 900 LBS, 1500 LBS, 2500 LBS
Types	Threaded, Plate, Screwed, Forged.
Supporting material	Gasket, Ring Joint, Flange Bolts
Size range	1/2" (15 NB) to 48" (1200NB) DN10~DN5000
Production technique	Forged, machined and Heat treated
Available Flange Type	Weld Neck Flanges, RTJ Flanges, Slip On Flanges, Spectacle Blind Flanges, Flanges Gaskets, Square Flanges, Standard Insert Flanges, High Hub Blinds Flanges, Flat Flanges, forged flanges, Weldo / Nipo Flanges, Jacket Insert Flanges, Tongue groove Flanges, Blind Flanges, Socket Weld Flanges, Large diameter Flanges, Long Weld Neck Flanges, Spacer Blinds, SWRF Flanges, SORF Flanges, Angle Face Rings Flanges, Spades Ring Spacers Flanges, WNRF Flanges, Screwed Flanges, Insert Flanges, flanges bolts, cf flange, Lap Joint Flanges, ASME B16.36 Orifice Flanges, Plate Flange, Expander Flanges, Ring Type Joint Flanges, Loose Flanges, Reducing Flanges, puddle flange, Threaded Flanges, blank flange, vacuum flange.
Connect Type/ Flange Face Type	Ring Type Joint (RTJ), Flat Face (FF), Tongue & Groove, Small Male-Female (SMF), Lap-Joint Face (LJF), Raised Face (RF), Large Male-Female (LMF), Small Tongue.
Custom design	As per your drawing
Test	Direct-reading Spectrograph, X-ray detector, UItrasonic flaw detector, Magnetic particle detector, Hydrostatic testing machine.
Origin	Indian / USA / Korean / West Europe / Japan
Pressure Class	PN 6 TO PN 100
Thickness	Normal Pipe Size ≤ 18
Bore Diameter	Normal Pipe ≤ 10
High Temperature	Above 200°C (400°F) For Class 150 Or Above 400°C (750°F)
Low Temperature	Above -29 Degree C (−20°F)
Coating/Surface Treatment:	Zinc Plated, Anti-rust Paint, Oil Black Paint, Yellow Transparent, Cold and Hot Dip Galvanized.
European/African/Russian Standard Flanges	Available
Gaskets Types	Full Face, Metallic Ring, Flat Ring Gasket
Marking Standard	Name of Manufacturer
	Schedule
	Type of Flange Facing
	Pressure Class
	Nominal Pipe Size, etc
Test Certificates	EN 10204/3.1B, NACE MR0103, NACE MR0175
	Raw Materials Certificate
	100% Radiography Test Report
	Third Party Inspection Report, etc

Flange Type Available

Equivalent Grade

STANDARD	WERKSTOFF NR.	UNS
Cupro Nickel 90/10	2.0872	C70600
Cupro Nickel 70/30	2.0882	C71500

Chemical Properties

Grade	Copper	Manganese	Lead	Nickel	Iron	Zinc
Cupro Nickel 90/10	88.6 Minimum	1.0 Maximum	0.05 Maximum	9-11 Maximum	1.8 Maximum	1 Maximum
Cupro Nickel 70/30	65 Minimum	1.0 Maximum	0.05 Maximum	29-33 Maximum	0.4-1.0 Maximum	1 Maximum

Mechanical Properties

Density	Melting Point	Tensile Strength	Yield Strength	Elongation
0.323 lb/in3 at 68 F	2260 F	50000 psi	20000 psi	30 %
0.323 lb/in3 at 68 F	2260 F	50000 psi	20000 psi	30 %

Copper Nickel Flange Dimensions Class-150

Nominal Pipe Size NPS (inches)	Class 150
	Diameter of Flange (inches)	No. of Bolts	Diameter of Bolts (inches)	Diameter of Bolt Holes (inches)	Bolt Circle (inches)
1/4	3-3/8	4	1/2	0.62	2-1/4
1/2	3-1/2	4	1/2	0.62	2-3/8
3/4	3-7/8	4	1/2	0.62	2-3/4
1	4-1/4	4	1/2	0.62	3-1/8
1-1/4	4-5/8	4	1/2	0.62	3-1/2
1-1/2	5	4	1/2	0.62	3-7/8
2	6	4	5/8	0.75	4-3/4
2-1/2	7	4	5/8	0.75	5-1/2
3	7-1/2	4	5/8	0.75	6
3-1/2	8-1/2	8	5/8	0.75	7
4	9	8	5/8	0.75	7-1/2
5	10	8	3/4	0.88	8-1/2
6	11	8	3/4	0.88	9-1/2
8	13-1/2	8	3/4	0.88	11-3/4
10	16	12	7/8	1	14-1/4
12	19	12	7/8	1	17
14	21	12	1	1.12	18-3/4
16	23-1/2	16	1	1.12	21-1/4
18	25	16	1-1/8	1.25	22-3/4
20	27-1/2	20	1-1/8	1.25	25
24	32	20	1-1/4	1.38	29-1/2

B16.5 Copper Nickel Flange Dimensions Class-300

Nominal Pipe Size NPS (inches)	Class 300
	Diameter of Flange (inches)	No. of Bolts	Diameter of Bolts (inches)	Diameter of Bolt Holes (inches)	Bolt Circle (inches)
1/4	3-3/8	4	1/2	0.62	2-1/4
1/2	3-3/4	4	1/2	0.62	2-5/8
3/4	4-5/8	4	5/8	0.75	3-1/4
1	4-7/8	4	5/8	0.75	3-1/2
1-1/4	5-1/4	4	5/8	0.75	3-7/8
1-1/2	6-1/8	4	3/4	0.88	4-1/2
2	6-1/2	8	5/8	0.75	5
2-1/2	7-1/2	8	3/4	0.88	5-7/8
3	8-1/4	8	3/4	0.88	6-5/8
3-1/2	9	8	3/4	0.88	7-1/4
4	10	8	3/4	0.88	7-7/8
5	11	8	3/4	0.88	9-1/4
6	12-1/2	12	3/4	0.88	10-5/8
8	15	12	7/8	1	13
10	17-1/2	16	1	1.12	15-1/4
12	20-1/2	16	1-1/8	1.25	17-3/4
14	23	20	1-1/8	1.25	20-1/4
16	25-1/2	20	1-1/4	1.38	22-1/2
18	28	24	1-1/4	1.38	24-3/4
20	30-1/2	24	1-1/4	1.38	27
24	36	24	1-1/2	1.62	32

Pressure Class/ Rating

ASME/ANSI B 16.5	Lap Joint Flange, Ring Type Joint Flange, Threaded Flange, Blind Flange, High Hub Blind Flange, Socket Weld Flange, Slip on Flange, Welding Neck Flange.
PRESSURE CLASS	150, 300, 400, 600, 900, 1500, 2500
ASME/ANSI B 16.47	Blind Flange [Series A & B], Welding Neck Flange.
PRESSURE CLASS	75, 150, 300, 400, 600, 900
ASME/ANSI B 16.36	Slip on Flange, Threaded Flange, Welding Neck Flange.
PRESSURE CLASS	300, 400, 600, 900, 1500, 2500
BS 4504 SEC 3.1	Plate Flange, Welding Neck Flange, Hubbed Slip on Flange, Lapped Pipe End Flange, Loose Plate With Weld Neck Flange, Hubbed Threaded Flange, Blank Flange, Loose Plate Flange.
PRESSURE CLASS	PN 2.5 TO PN 40
BS 4504[PART 1]	Blank Flange, Loose Plate With Weld On Plate Collar, Welding Neck Flange, Plate Flange, Hubbed Slip-On Hubbed Threaded.
PRESSURE CLASS	PN 2.5 TO PN 400
BS 1560 BOSS	Blind Flange, Screwed Boss Flange, Welding Neck Flange,Slip-On Flange, Lapped Flange, Socket Welding Flange.
PRESSURE CLASS	150, 300, 400, 600, 900, 1500, 2500
BS10	Screwed Boss Flange, Plate Slip-On Flange, Slip-On Boss Flange, Blind Flange, Welding Neck Flange.
TABLE	D, E, F, H
DIN FLANGES	DIN 2527, 2632, 2635, 2673, 2566, 2655, 2631, 2627, 2634, 2576, 2636, 2629, 2633, 2573, 2656, 2638, 2637, 2642, 2641, 2628
PRESSURE CLASS	PN 6 TO PN 100

Cupro Nickel Flange Weight Chart

Nominal Pipe Size		Dimension		Weight in Kg
Normal Pipe Size (Inche)	Diameter Nominal	Flange Outer Diameter in MM	Flange Thickness in MM	Socket Weld	Weld Neck	Blind
8	200	342.9	28.4	12.1	17.6	19.6
3/4	20	98.6	12.7	0.6	0.7	0.6
1	25	108	14.2	0.8	1	0.9
1 1/4	32	117.3	15.7	1	1.3	1.2
1 1/2	40	127	17.5	1.3	1.7	1.5
2	50	152.4	19.1	2.1	2.6	2.4
2 1/2	65	177.8	22.4	3.3	4.1	3.9
1/2	15	88.9	11.2	0.4	0.5	0.4
3	80	190.5	23.9	3.9	4.9	4.9
24	600	812.8	47.8	86.9	115	185.0
3 1/2	90	215.9	23.9	4.8	6.1	6.2
4	100	228.6	23.9	5.3	6.8	7.0
5	125	254	23.9	6.1	8.6	8.6
6	150	279.4	25.4	7.5	10.6	11.3
10	250	406.4	30.2	16.5	24	28.6
14	350	533.4	35.1	34.6	48.4	58.1
12	300	482.6	31.8	26.2	36.5	43.2
16	400	596.9	36.6	44.8	60.6	76.1
18	450	635	39.6	48.9	68.3	93.7
20	500	698.5	42.9	61.9	84.5	122.0