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Cupro Nickel 70/30 Bolts Manufacturer & Exporter in India

Explore Cupro Nickel 70/30 Bolts Manufacturer & Exporter in India manufactured for demanding industrial applications with reliable strength, corrosion resistance and compliance with international standards.
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-200

Min Temp

1000

Max Temp

🌡

1000

Suitable for continuous service up to approximately 1000°C under typical operating conditions.

⚡

700

Typical tensile strength around 700 MPa depending on product form and heat treatment.

🛡

Excellent

Excellent corrosion resistance in a wide range of industrial environments.

⚖

8.9

Typical density is approximately 8.9 g/cm³.

Product Overview

What are Cupro Nickel 70/30 Bolts?

Cupro Nickel 70/30 bolts are corrosion-resistant fasteners manufactured from a copper-nickel alloy containing 70% copper and 30% nickel, designated as UNS C71500. These bolts are produced from ASTM B151 or B151M bar stock and are renowned for their exceptional resistance to seawater corrosion, biofouling, and stress corrosion cracking. The addition of iron and manganese enhances their mechanical strength and imparts superior resistance to erosion and impingement attack in high-velocity marine environments.

Cupro Nickel 70/30 bolts are widely specified for marine, offshore, and desalination plant applications where long-term durability and reliability in aggressive chloride-rich environments are critical. They are compliant with international standards such as ASTM B151, ASME SB151, and DIN 2.0882, ensuring consistent quality and traceability for demanding engineering projects.

Quick Specifications

MaterialCupro Nickel 70/30
UNS NumberC71500
DIN Number2.0882
Material StandardASTM B151
Bolt Standard (Metric)DIN 931 / DIN 933 / ISO 4014
Bolt Standard (Inch)ASME B18.2.1
Thread FormISO Metric / UNC / UNF
Diameter RangeM6-M64 / ¼"-2½"
Tensile Strength245 MPa (35.5 ksi) min
Yield Strength105 MPa (15.2 ksi) min
HardnessMax 80 HRB / 150 HB
? All material certified by NABL-accredited laboratory. PMI and ferrite testing available on request.

Complete the Fastener Set

Other Cupro Nickel 70/30 Fastener Products Available from RealBolt

RealBolt also manufactures the complete Cupro Nickel 70/30 fastener range from certified copper-nickel alloy bar stock, including Cupro Nickel 70/30 Nuts, Cupro Nickel 70/30 Screws, Cupro Nickel 70/30 Washers, Cupro Nickel 70/30 Studs, and Cupro Nickel 70/30 Threaded Rods. All Cupro Nickel 70/30 fastener types are produced to ASTM with full EN 10204 MTC 3.1/3.2 documentation.
Cupro Nickel 70/30 Nuts
Cupro Nickel 70/30 Screws
Cupro Nickel 70/30 Washers
Cupro Nickel 70/30 Studs
Cupro Nickel 70/30 Threaded Rods

Technical Data

Cupro Nickel 70/30 Bolts Dimensions, Sizes & Thread Standards

Cupro Nickel 70/30 Bolts are available in metric M6–M100 and inch ¼″–4″ as standard. Per DIN 931 (partial thread) / DIN 933 (full thread) / ISO 4014. Custom lengths in 5mm increments. Inch dimensions available per ASME B18.2.1. All Cupro Nickel 70/30 bolts dimensions conform to applicable DIN, ISO, and ASME B18 standards.

Hex Bolt Dimensions - Metric (DIN 931 / ISO 4014)

Size (M)Pitch (mm)A/F (mm)Head Ht (mm)Min L (mm)Max L (mm)
M61.0104.010200
M81.25135.312250
M101.5176.416300
M121.75197.520400
M162.02410.025500
M202.53012.530600
M243.03615.040600
M303.54618.750800
M364.05522.5601000
M424.56526.0801000
M485.07530.01001200
M565.58535.01201500
M646.09540.01402000

Dimensional & Material Standards

StandardCoversThread
DIN 931Hex bolts, partial threadMetric
DIN 933Hex bolts, full threadMetric
ISO 4014Hex head screws, partialMetric
ISO 4017Hex head screws, fullMetric
ASME B18.2.1Hex & heavy hex boltsUNC/UNF
ASME B16.5Stud bolts for flangesUNC
MSS SP-75Stud bolts, high-pressureUNC
Material StandardRequirement
ASTM B151Bar/rod - UNS C71500
ASTM B467Forged/cold worked fasteners
EN 12163Copper and copper alloys
EN 10204 3.1Mill test certificate
EN 10204 3.2TPI-witnessed MTC

Material Chemistry

Cupro Nickel 70/30 Chemical Composition

Cupro Nickel 70/30 Bolts are manufactured from a copper-nickel alloy with nickel (9–33%), iron (1–2%), and manganese additions per ASTM and MIL-C-15726. Iron additions are essential — they form a protective surface film that resists seawater impingement and erosion-corrosion at flow velocities up to 3.5 m/s in shipboard piping and offshore cooling systems.

Chemical Composition per ASTM B151

ElementComposition (%)
Copper (Cu)65.0 min
Nickel (Ni) incl. Cobalt29.0-33.0
Iron (Fe)0.4-1.0
Manganese (Mn)0.5-1.0
Zinc (Zn)1.0 max
Lead (Pb)0.05 max
Phosphorus (P)0.02 max
Other elements0.30 max (total)
? All heats verified by NABL-accredited spectrometry. PMI available on request.

Why Cupro Nickel 70/30 Alloy Composition Matters for Bolts

Nickel (29–33%) — Seawater Corrosion Resistance
The high nickel content in Cupro Nickel 70/30 bolts provides outstanding resistance to chloride-induced corrosion, making them ideal for marine and desalination plant bolting where stainless steel fails.
Iron & Manganese — Erosion & Impingement Resistance
Iron and manganese additions improve resistance to high-velocity seawater and turbulent flow, preventing erosion and impingement attack under bolt heads and washers.
Low Impurity Levels
Strict control of lead, phosphorus, and other impurities ensures Cupro Nickel 70/30 bolts maintain ductility and toughness, even after years of service in aggressive environments.

Fastener Performance

Cupro Nickel 70/30 Bolts Mechanical Properties & Torque Reference

The table below lists mechanical properties and torque reference for Cupro Nickel 70/30 Bolts per ASTM. Cupro Nickel 70/30 bolts achieve 700 MPa tensile strength, with hardness, yield, and elongation values verified by NABL-accredited testing and reported in the EN 10204 MTC.

Bolt SizeDry (Nm)Lubricated (Nm)Clamp Load (kN)
M12383013
M16907231
M2018014449
M2431024871
M30620496113
M361080864164
M4217201376226
M4825502040299
?? Anti-galling: Use copper-based anti-seize (Molykote Cu-7439). Lubricated values assume K=0.16. Avoid nickel-based anti-seize for copper alloys.

Industry Applications

Cupro Nickel 70/30 Bolts Applications — Industries & End Uses

Cupro Nickel 70/30 Bolts from RealBolt are specified across marine shipbuilding, offshore seawater systems, and naval defence where excellent corrosion resistance and 700 MPa tensile strength are required for reliable fastener performance. Click each industry below for detailed application examples.
Cupro Nickel 70/30 bolts are the preferred choice for hull penetrations, seawater piping flanges, and propeller shaft couplings in naval and commercial vessels. Their resistance to biofouling and seawater corrosion ensures long-term reliability in submerged and splash-zone applications.
Used for high-pressure flange connections, pump casings, and heat exchanger channel covers in reverse osmosis and multi-stage flash desalination plants. Cupro Nickel 70/30 bolts withstand brine, chlorinated water, and high-velocity flow without suffering from impingement or pitting.
Specified for riser clamps, splash zone supports, and subsea pipeline flange connections where resistance to marine growth and chloride attack is critical. Cupro Nickel 70/30 bolts are compliant with NORSOK and Shell DEP for offshore structural fasteners.
Bolts for steam condenser waterboxes, cooling water intake screens, and heat exchanger tube sheets in thermal and nuclear power plants. Their non-sparking and anti-microbial properties make them ideal for critical cooling circuits.

Cupro Nickel 70/30 Bolts Standards & International Certifications

Cupro Nickel 70/30 Bolts from RealBolt Engineering Industries are manufactured to internationally recognised fastener dimensional standards covering thread form, tolerances, strength grades, and quality requirements. Every batch ships with EN 10204 MTC 3.1/3.2, Lloyds Register or DNV certification, NACE MR0175, and PMI (XRF) reports — available on request for all orders.
Standards
DIN 931 DIN 933 ISO 4014 ISO 4017 ASME B18.2.1 BS 1768 BS 3692 IS 1364 IS 1367
Certifications
ISO 9001:2015NABL LabPED 2014/68/EUMTC 3.1 / 3.2

Buy Cupro Nickel 70/30 Bolts from India's Leading Manufacturer — Get a Competitive Quote Today

Partner with RealBolt — India’s leading manufacturer of certified Cupro Nickel 70/30 Bolts — for competitive pricing, EN 10204 MTC 3.1/3.2 documentation, and fast Mumbai dispatch. Standard sizes are ex-stock; custom dimensions accepted with 2–3 week lead time. Request your quote today.
022-6743-7972
+91 90226 36025
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Answers for Buyers

Cupro Nickel 70/30 Bolts — Frequently Asked Questions

Browse expert answers to common questions about Cupro Nickel 70/30 Bolts from RealBolt — covering 70/30 vs 90/10 selection, ASTM B151, seawater immunity, MIL-C-15726 approval, sizes, and Lloyds/DNV certification. Contact our technical team directly for project-specific guidance on Cupro Nickel 70/30 bolts selection and pricing.
Cupro Nickel 70/30 bolts are available to DIN 931 (metric partial thread), DIN 933 (metric full thread), ISO 4014/4017, and ASME B18.2.1 (inch hex and heavy hex). Stud bolts for flanges are supplied per ASME B16.5 and MSS SP-75. Custom thread forms (BSW, BSF, Whitworth, BSPP) can be manufactured on request with a typical lead time of 2-3 weeks.
Use copper-based anti-seize compound (such as Molykote Cu-7439 or Loctite LB 8008 C5-A) for Cupro Nickel 70/30 bolts. Apply to threads and bearing surfaces to prevent galling and facilitate disassembly. Avoid nickel-based or graphite-based anti-seize, as these may cause galvanic corrosion with copper alloys.
Yes – Cupro Nickel 70/30 bolts are specifically engineered for continuous immersion in seawater and brine. They are immune to chloride pitting, crevice corrosion, and biofouling, making them ideal for submerged marine hardware, desalination plants, and offshore structures. No special coatings or cathodic protection are required.
No formal MOQ for standard sizes (M8-M36) held ex-stock – we supply from single pieces for urgent repairs. Custom sizes or non-standard threads have an MOQ of 10 kg. Flange stud bolt sets are supplied by the set with no minimum. Quantity price breaks at 50 pcs, 200 pcs, and 500 pcs.

Industrial Cities We Serve:

  • Ahmedabad
  • Aurangabad
  • Bengaluru
  • Chennai
  • Coimbatore
  • Faridabad
  • Gandhidham
  • Greater Noida
  • Gurugram
  • Hazira
  • Hosur
  • Hyderabad
  • Jamnagar
  • Jamshedpur
  • Ludhiana
  • Mumbai
  • Mundra
  • Mysuru
  • Nagpur
  • Nashik
  • Navi Mumbai
  • Noida
  • Pune
  • Rajkot
  • Sanand
  • Surat
  • Thane
  • Tiruppur
  • Vadodara
  • Visakhapatnam

Countries We Export To:

  • US
  • Canada
  • Mexico
  • Germany
  • UK
  • France
  • Italy
  • Spain
  • Netherlands
  • Belgium
  • Poland
  • Sweden
  • Norway
  • Denmark
  • Turkey
  • UAE
  • Saudi Arabia
  • Qatar
  • Oman
  • Kuwait
  • Bahrain
  • South Africa
  • Egypt
  • Nigeria
  • Australia
  • New Zealand
  • Singapore
  • Malaysia
  • Indonesia
  • Thailand
  • Vietnam
  • South Korea
  • Japan
  • Brazil