Get a quote

Cupro Nickel 70/30 Bolts

  • Home
  • Cupro Nickel 70/30 Bolts
Manufacturer, Exporter & Supplier of Cupro Nickel 70/30 Bolts

Cupro Nickel 70/30 Bolts for Marine & Industrial Corrosion-Resistant Applications

Cupro Nickel 70/30 Bolts are high-performance fastening components manufactured from a copper-nickel alloy containing approximately 70% copper and 30% nickel, engineered specifically for severe corrosion environments such as seawater, brine systems, and chemical processing plants. These bolts are widely used in marine engineering, offshore oil & gas platforms, desalination plants, and heat exchanger assemblies where standard stainless steels begin to fail under chloride exposure.

Cupro Nickel 70/30 Bolts Manufacturer

The material, often designated as C71500, offers an exceptional balance of mechanical strength and resistance to biofouling and stress corrosion cracking. Cupro Nickel 70/30 Bolts maintain structural integrity even under continuous saltwater immersion, making them a preferred choice for critical submerged assemblies and high-humidity industrial zones.

Manufactured with controlled metallurgical precision, KK Fasteners supplies these bolts to global EPC contractors and marine equipment manufacturers, ensuring full traceability and compliance with international fastener standards. The focus is not only durability but also predictable performance under dynamic loading and thermal cycling conditions, which is essential for long-life offshore infrastructure.

Technical Specification List Of Cupro Nickel 70/30 Bolts

Parameter Specification
Material Cupro Nickel Alloy 70/30 (CuNi 70/30 – UNS C71500)
Chemical Composition Copper (Cu): ~65–70% | Nickel (Ni): ~29–32% | Iron & Manganese: Trace elements
Standards ASTM B151, ASTM B164, BS 2871, EN 12449
Size Range M6 to M64 | 1/4" to 2-1/2"
Length Range 10 mm to 500 mm (custom sizes available)
Thread Type Metric (M), UNC, UNF, BSW
Strength Grade Tensile Strength: 350–550 MPa | Yield Strength: ~125–240 MPa
Hardness 75–100 HRB (Rockwell B Scale)
Temperature Resistance -50°C to 300°C continuous service
Finish / Surface Self-colored, polished, anti-galling treated, optional passivated finish
Type Variants Hex Bolts, Heavy Hex Bolts, Stud Bolts, Socket Head Bolts, U-Bolts
Corrosion Resistance Excellent resistance to seawater, brine, chloride environments, and biofouling
Magnetic Property Non-magnetic / Low magnetic permeability
Inspection & Testing Dimensional inspection, tensile testing, hardness test, PMI, ultrasonic testing (optional)

Chemical Composition Of Cupro Nickel 70/30 Bolts

Cu-Ni 70/30 Cu Pb Mn Fe Zn Ni
88.6 min 0.05 max 1.0 max 1.8 max 1 max 9-11 max

Mechanical Properties Of Cupro Nickel 70/30 Bolts

Density Melting Point Yield Strength (0.2%Offset) Tensile Strength Elongation
8.1 g/cm3 1443 °C (2430 °F) Psi – 35,000, MPa – 241 Psi -80,000, MPa -551 30 %

Equivalent Grades of Cupro Nickel 70/30 Bolts

STANDARD UNS WERKSTOFF NR.
Cupro Nickel 70/30 C70600 2.0872

Cupro Nickel 70/30 Hex Bolts Dimensions

Hex Bolt Dimension

All measurements in millimeters

NOMINAL SIZE (D)
BODY DIAMETER
BOLT HEAD THICKNESS
ACROSS THE FLATS
ACROSS CORNERS
D (MAX)
D (MIN)
H (MAX)
H (MIN)
F (MAX)
F (MIN)
C (MAX)
C (MIN)
m10
10.00
9.78
6.63
6.17
17.00
15.73
18.48
17.77
m12
12.00
11.73
7.76
4.24
19.00
17.73
20.78
20.03
m14
14.00
13.73
9.09
8.51
22.00
20.67
24.25
23.35
m16
16.00
15.73
10.32
9.68
24.00
23.67
27.71
26.75
m20
20.00
19.67
12.88
12.12
30.00
29.16
34.64
32.95
m24
24.00
23.67
15.44
14.56
36.00
35.00
41.57
39.55
m30
30.00
29.67
19.48
17.92
46.00
45.00
53.12
50.85
m36
36.00
35.61
23.38
21.63
55.00
53.80
63.51
60.79
m42
42.00
41.38
26.97
25.03
65.00
62.90
75.06
71.71
m48
48.00
47.38
31.07
28.93
75.00
72.60
86.60
82.76
m56
56.00
55.26
36.2
33.80
85.00
82.20
98.15
93.71
m64
64.00
63.26
41.32
38.68
95.00
91.80
109.70
104.65
m72
72.00
71.26
46.45
43.55
105.00
101.40
121.24
115.60
m80
80.00
79.26
51.58
48.42
115.00
111.00
132.72
126.54
m90
90.00
89.13
57.74
54.26
130.00
125.50
150.11
143.07
m100
90.00
99.13
63.9
60.10
145.00
140.00
167.43
159.60

Cupro Nickel 70/30 Bolts Weight Chart

MM THREADS AS PER IS 1363/67
APPROXIMATE WEIGHT IN KGS FOR 100 NOS
LENGTH DIAMETER
M 5 M 6 M 8 M 10 M 12 M 14 M 16 M 18 M 20 M 22
16 mm 0.448 0.743 1.590 3.211
20 mm 0.598 0.812 1.711 3.411 4.892
25 mm 0.660 0.897 1.871 3.660 5.252 8.170
30 mm 0.737 1.010 2.070 3.912 5.574 9.690 10.707 18.657
35 mm 0.804 1.120 2.271 4.223 5.974 10.000 11.416 16.026 19.608
40 mm 0.881 1.230 2.470 4.533 6.410 10.288 12.107 16.667 20.747
45 mm 0.958 1.340 2.671 4.840 6.859 10.504 12.821 17.241 21.739
50 mm 1.030 1.450 2.870 5.155 7.299 11.261 13.624 17.857 22.727 28.409
55 mm 1.560 3.071 5.464 7.740 11.628 14.409 18.868 23.810 30.120
60 mm 1.670 3.270 5.774 8.183 12.255 15.244 20.000 25.126 32.051
65 mm 1.781 3.472 6.083 8.621 12.626 16.026 21.008 26.455 34.014
70 mm 1.890 3.671 6.394 9.058 12.987 16.835 22.124 27.778 35.461
75 mm 2.000 3.873 6.702 9.506 13.228 17.606 23.256 29.070 39.063
80 mm 2.111 4.072 7.013 10.000 13.889 18.248 24.510 30.303 40.000
90 mm 4.472 7.634 10.917 14.925 19.841 26.042 33.113 41.667
100 mm 4.873 8.251 11.820 16.340 21.459 27.778 35.714 46.296
110 mm 8.881 12.723 17.730 23.041 31.250 38.168 47.170
120 mm 9.506 13.624 18.797 24.631 32.895 40.984 50.000
130 mm 10.101 14.535 20.000 26.316 34.722 43.478 52.632
140 mm 10.707 15.432 20.833 27.933 35.461 46.296 55.556
150 mm 11.312 16.340 22.222 29.412 37.594 48.544 58.824
160 mm 11.905 17.241 24.272 31.056 40.984 50.505 61.728
170 mm 12.500 18.116 32.680 53.191 64.935
180 mm 13.123 19.011 26.882 34.247 55.556 67.568
190 mm 13.736 19.920 35.971 58.140 70.423
200 mm 14.327 20.833 29.586 37.594 49.020 60.976 73.529
220 mm 15.528 22.624 40.650 65.789 79.365
240 mm 16.722 24.510 43.860 71.429 84.746
250 mm 17.301 25.381 45.455 74.627 87.719
260 mm 17.921 26.316 47.170 76.923 90.909
280 mm 19.157 28.090 50.505 81.967 98.039
300 mm 20.325 29.940 53.763 87.719 104.167
320 mm 31.646 56.818 92.593
340 mm 33.557 60.241 98.039
360 mm 35.211 63.291 104.167
380 mm 37.037 66.667 108.696
400 mm 39.063 69.444 113.636

ASME SB151 Cupro Nickel 70/30 Stud Bolt Size Chart

Class 150 Flanges ASME B16.5 (Stud bolt sizes) Length of Stud Bolts
NPS Outside Diameter of Flange The diameter of Bolt Circle The diameter of Bolt Holes Number of Bolts Diameter of Bolts Raised Face
0.06 in		 Ring Joint
1/2 3 1/2 2 3/8 5/8 4 1/2 2 1/4 –
3/4 3 7/8 2 3/4 5/8 4 1/2 2 1/2 –
1 4 1/4 3 1/8 5/8 4 1/2 2 1/2 3
1 1/4 4 5/8 3 1/2 5/8 4 1/2 2 3/4 3 1/4
1 1/2 5 3 7/8 5/8 4 1/2 2 3/4 3 1/4
2 6 4 3/4 3/4 4 5/8 3 1/4 3 3/4
2 1/2 7 5 1/2 3/4 4 5/8 3 1/2 4
3 7 1/2 6 3/4 4 5/8 3 1/2 4
3 1/2 8 1/2 7 3/4 8 5/8 3 1/2 4
4 9 7 1/2 3/4 8 5/8 3 1/2 4
5 10 8 1/2 7/8 8 3/4 3 3/4 4 1/4
6 11 9 1/2 7/8 8 3/4 4 4 1/2
8 13 1/2 11 3/4 7/8 8 3/4 4 1/4 4 3/4
10 16 14 3/4 1 12 7/8 4 1/2 5
12 19 17 1 12 7/8 4 3/4 5 1/4
14 21 18 3/4 1 1/8 12 1 5 1/4 5 3/4
16 23 1/2 21 1/4 1 1/8 16 1 5 1/4 5 3/4
18 25 22 3/4 1 1/4 16 1 1/8 5 3/4 6 1/4
20 27 1/2 25 1 1/4 20 1 1/8 6 1/4 6 3/4
24 32 29 1/2 1 1/4 20 1 1/4 6 3/4 7 1/4
Class 300 Flanges ASME B16.5 Length of Stud Bolts
NPS Outside Diameter of Flange The diameter of Bolt Circle The diameter of Bolt Holes Number of Bolts Diameter of Bolts Raised Face
0.06 in		 Ring Joint
1/2 3 3/4 2 5/8 5/8 4 1/2 2 1/2 3
3/4 4 5/8 3 1/4 3/4 4 5/8 3 3 1/2
1 4 7/8 3 1/2 3/4 4 5/8 3 3 1/2
1 1/4 5 1/4 3 7/8 3/4 4 5/8 3 1/4 3 3/4
1 1/2 6 1/8 4 1/2 7/8 4 3/4 3 1/2 4
2 6 1/2 5 3/4 8 5/8 3 1/2 4
2 1/2 7 1/2 5 7/8 7/8 8 3/4 4 4 1/2
3 8 1/4 6 5/8 7/8 8 3/4 4 1/4 4 3/4
3 1/2 9 7 1/4 7/8 8 3/4 4 1/4 5
4 10 7 7/8 7/8 8 3/4 4 1/2 5
5 11 9 1/4 7/8 8 3/4 4 3/4 5 1/4
6 12 1/2 10 5/8 7/8 12 3/4 4 3/4 5 1/2
8 15 13 1 12 7/8 5 1/2 6
10 17 1/2 15 1/4 1 1/8 16 1 6 1/4 6 3/4
12 20 1/2 17 3/4 1 1/4 16 1 1/8 6 3/4 7 1/4
14 23 20 1/4 1 1/4 20 1 1/8 7 7 1/2
16 25 1/2 22 1/2 1 3/8 20 1 1/4 7 1/2 8
18 28 24 3/4 1 3/8 24 1 1/4 7 3/4 8 1/4
20 30 1/2 27 1 3/8 24 1 1/4 8 8 3/4
24 36 32 1 5/8 24 1 1/2 9 10

Different Types of Cupro Nickel 70/30 Bolts

  • Cupro Nickel 70/30 Flanged Bolts
  • Cupro Nickel 70/30 Hex Bolts
  • Cupro Nickel 70/30 U Bolts
  • Cupro Nickel 70/30 Shoulder Bolts
  • Cupro Nickel 70/30 Eye Bolts
  • Cupro Nickel 70/30 Heavy Hex Bolts
  • Cupro Nickel 70/30 Hollow Hex Bolts
  • Cupro Nickel 70/30 Hollow Allen Bolts
  • Cupro Nickel 70/30 Machine Bolts
  • Cupro Nickel 70/30 Socket Head Bolts
  • Cupro Nickel 70/30 Hex Flange Bolts
  • Cupro Nickel 70/30 Lag Bolts
  • Cupro Nickel 70/30 J Bolts
  • Cupro Nickel 70/30 Elevator Bolts
  • Cupro Nickel 70/30 Hanger Bolts
  • Cupro Nickel 70/30 Carriage Bolts
  • Cupro Nickel 70/30 Allen Bolts
  • Cupro Nickel 70/30 Anchor Bolts
  • Cupro Nickel 70/30 Countersunk Bolts
  • Cupro Nickel 70/30 Stud Bolts
  • Cupro Nickel 70/30 Square Head Bolts
  • Cupro Nickel 70/30 Stud Bolts
  • Cupro Nickel 70/30 Full Threaded Stud Bolts
  • Cupro Nickel 70/30 Tap End Stud Bolts
  • Cupro Nickel 70/30 Double End Stud Bolts
  • Cupro Nickel 70/30 Reduced Shank Stud Bolts
  • Cupro Nickel 70/30 Flange Bolting Stud Bolts
  • Cupro Nickel 70/30 Weld Studs
  • Cupro Nickel 70/30 Threaded Rods
  • Cupro Nickel 70/30 Hex Head Bolts
  • Cupro Nickel 70/30 Jack Bolts
  • Cupro Nickel 70/30 Structural Bolts
  • Cupro Nickel 70/30 Step Bolts
  • Cupro Nickel 70/30 Square Head Machine Bolts
  • Cupro Nickel 70/30 Plow Bolts
  • Cupro Nickel 70/30 Metric Bolts
  • Cupro Nickel 70/30 Hex Tap Bolts
  • Cupro Nickel 70/30 Hex Machine Bolts
  • Cupro Nickel 70/30 Shoulder Eye Bolts
  • Cupro Nickel 70/30 Serrated Flange Bolts
  • Cupro Nickel 70/30 Turned Eye Bolts
  • Cupro Nickel 70/30 Long Bolts
  • Cupro Nickel 70/30 Bent Bolts
  • Cupro Nickel 70/30 Square U Bolts
  • Cupro Nickel 70/30 Timber Bolts
  • Cupro Nickel 70/30 15 Point Flange Bolts
  • Cupro Nickel 70/30 Button Head Bolts
  • Cupro Nickel 70/30 Hexagon Flange Bolts
  • Cupro Nickel 70/30 Stud Bolts
  • Cupro Nickel 70/30 Hexagon Head Bolts
  • Cupro Nickel 70/30 Lifting Eye Bolts
  • Cupro Nickel 70/30 T Bolts
  • Cupro Nickel 70/30 Threaded Bolts

Key Technical Features

  • Exceptional seawater corrosion resistance: The CuNi 70/30 composition forms a stable protective oxide layer, preventing pitting and crevice corrosion in continuous marine exposure environments.
  • High resistance to biofouling: Minimizes marine organism attachment, reducing maintenance cycles in offshore platforms and submerged structures.
  • Controlled mechanical strength: Offers tensile strength up to 550 MPa, ensuring reliable load-bearing performance in structural and pressure-retaining assemblies.
  • Excellent thermal stability: Performs reliably under fluctuating thermal conditions commonly found in heat exchangers and desalination systems.
  • Dimensional precision compliance: Manufactured within tight tolerances (ISO/DIN class standards), ensuring compatibility with precision-engineered flanged and structural systems.
  • Low magnetic permeability: Suitable for sensitive marine navigation, offshore instrumentation, and electronic housings where magnetic interference must be avoided.
  • Superior anti-galling characteristics: Reduces thread seizure during assembly in submerged or high-humidity conditions, improving maintenance efficiency.

Industry Applications

Cupro Nickel 70/30 Bolts are primarily used in environments where corrosion resistance is critical for operational safety and lifecycle cost reduction. They are not general-purpose fasteners but engineered components for high-value industrial systems.

  • Marine Engineering & Shipbuilding — Used in hull fittings, seawater piping systems, and propulsion assemblies exposed to continuous saltwater immersion.
  • Offshore Oil & Gas Platforms — Securing structural modules, subsea equipment, and riser assemblies in aggressive offshore environments.
  • Desalination Plants — Installed in high-pressure seawater processing units and evaporator systems.
  • Heat Exchangers & Condensers — Used in tube sheet assemblies where thermal cycling and corrosive media are present.
  • Power Generation Plants — Applied in cooling water systems and turbine auxiliary piping networks.
  • Chemical Processing Industries — Suitable for chloride-rich and mildly acidic process environments.
  • Marine Defense Applications — Utilized in naval vessels and underwater equipment requiring non-magnetic, corrosion-resistant fastening.

Manufacturing & Quality Assurance

Cupro Nickel 70/30 Bolts are produced using controlled hot forging followed by precision CNC machining to achieve dimensional accuracy and consistent grain structure. The forging process enhances fatigue resistance and ensures uniform mechanical properties across production batches.

Each batch undergoes stringent quality inspection including dimensional verification, tensile strength testing, hardness measurement, and surface integrity checks. Traceability is maintained through heat-number-based identification systems to ensure full material accountability.

KK Fasteners implements ISO 9001:2015-certified quality systems, along with compliance to RoHS and REACH standards for global export requirements. This ensures every fastener meets stringent international industrial expectations before dispatch.

img
Icon

Wide Range of Quality Products

Explore our comprehensive range of products, ensuring you find the perfect solution for your specific requirements.

img
Icon

Competitive Pricing and Cost Savings

Save money without compromising on quality, thanks to our competitive prices and cost-effective options.

img
Icon

Exceptional Customer Service

Personalized assistance, prompt responses, and a commitment to meeting your needs, making your purchase process seamless.

Send us your Requirement for Cupro Nickel 70/30 Bolts

We can assure you one of best prices in the Industry. We respond to all enquiries with in 4-8 hours on all business days. Send us your requirement on inquiry@kkfasteners.com
Send Us Your Requirement
Contact

Cupro Nickel 70/30 Bolts - FAQs

Cupro Nickel 70/30 Bolts are high-performance fastening components made from a copper-nickel alloy containing approximately 70% copper and 30% nickel. They are specifically engineered for marine and seawater environments where resistance to corrosion, biofouling, and erosion is critical for long-term structural reliability.

CuNi 70/30 offers superior resistance to seawater corrosion compared to many stainless steels because it forms a stable, self-protecting oxide layer. It also performs better in high-velocity seawater systems, reducing erosion and maintaining integrity in offshore and submerged applications.

These bolts are commonly manufactured in compliance with ASTM B151 and ASTM B164 material standards. Depending on application requirements, they may also conform to DIN, ISO, BS, and EN fastener dimensional and performance standards for global compatibility.

They are widely used in marine engineering, offshore oil & gas platforms, desalination plants, heat exchangers, condensers, power generation cooling systems, and naval applications. Their primary role is to ensure reliable fastening in chloride-rich and seawater-exposed environments.

A reliable supplier should provide material traceability, ISO-certified quality systems, compliance with international standards, and consistent export documentation. Engineering support, inspection reports, and proven experience in marine-grade fasteners are also key evaluation factors when selecting a supplier.

Cupro Nickel 70/30 Bolts - Export Destination

Cupro Nickel 70/30 Bolts Supplier in North America
Antigua and Barbuda, Bahamas, Barbados, Belize, Canada, Costa Rica, Cuba, Dominica, Dominican Republic, El Salvador, Grenada, Guatemala, Haiti, Honduras, Jamaica, Mexico, Nicaragua, Panama, Saint Kitts and Nevis, Saint Lucia, Saint Vincent and the Grenadines, Trinidad and Tobago, United States.
Cupro Nickel 70/30 Bolts Supplier in South America
Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Falkland Islands, French Guiana, Guyana, Paraguay, Peru, Suriname, Uruguay, Venezuela.
Cupro Nickel 70/30 Bolts Supplier in Europe
Albania, Andorra, Austria, Belarus, Belgium, Bosnia and Herzegovina, Bulgaria, Croatia, Czech Republic (Czechia), Denmark, Estonia, Finland, France, Germany, Greece, Holy See, Hungary, Iceland, Ireland, Italy, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Moldova, Monaco, Montenegro, Netherlands, North Macedonia, Norway, Poland, Portugal, Romania, Russia, San Marino, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Ukraine, United Kingdom.
Cupro Nickel 70/30 Bolts Supplier in Asia
Afghanistan, Armenia, Azerbaijan, Bahrain, Bangladesh, Bhutan, Brunei, Cambodia, Cyprus, Georgia, India, Indonesia, Iran, Iraq, Israel, Japan, Jordan, Kazakhstan, Kuwait, Kyrgyzstan, Laos, Lebanon, Malaysia, Maldives, Mongolia, Myanmar, Nepal, Oman, Pakistan, Palestine, Philippines, Qatar, Saudi Arabia, Singapore, South Korea, Sri Lanka, State of Palestine, Syria, Taiwan, Tajikistan, Thailand, Timor-Leste, Turkey, Turkmenistan, United Arab Emirates, Uzbekistan, Vietnam, Yemen.
Cupro Nickel 70/30 Bolts Supplier in Australia
Australia, Fiji, Kiribati, Marshall Islands, Micronesia, Nauru, New Zealand, Palau, Papua New Guinea, Samoa, Solomon Islands, Tonga, Tuvalu, Vanuatu.

Cupro Nickel 70/30 Bolts deliver long-term reliability in environments where standard fasteners fail due to seawater corrosion and mechanical erosion. With controlled metallurgy and precision manufacturing, they ensure structural integrity in mission-critical marine systems.

KK Fasteners supports global engineering projects with traceable, specification-driven fastening solutions tailored for offshore, desalination, and industrial applications. Request a technical quotation or specification sheet to align your project requirements with engineered fastening performance.

request a quote
email us

Bolts Materials

Our Products

Types of Fasteners

download brochure