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Cupro Nickel 70/30 Screws Manufacturer & Exporter in India

Explore Cupro Nickel 70/30 Screws 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 Screws?

Cupro Nickel 70/30 screws are corrosion-resistant fasteners manufactured from a copper-nickel alloy containing 70% copper and 30% nickel, designated as UNS C71500. These screws are produced from ASTM B151 or B151M bar and rod, offering excellent resistance to seawater, brine, and marine atmospheres. The addition of iron and manganese enhances their resistance to impingement and erosion, making them ideal for marine and offshore applications.

Cupro Nickel 70/30 screws are widely specified for shipbuilding, desalination plants, and heat exchanger assemblies where long-term durability and resistance to biofouling are critical. They are non-magnetic, exhibit good ductility, and maintain mechanical integrity even after prolonged exposure to aggressive environments.

Quick Specifications

MaterialCupro Nickel 70/30
UNS NumberC71500
DIN Number2.0882
Material StandardASTM B151 / B151M
Screw Standard (Metric)DIN 912 / DIN 963 / ISO 4762
Screw Standard (Inch)ASME B18.3 / B18.6.3
Thread FormISO Metric / UNC / UNF
Diameter RangeM3-M48 / 1/8"-2"
Tensile Strength245 MPa (35 ksi) min
Yield Strength105 MPa (15 ksi) min
HardnessMax 80 HRB / 150 HB
? All material certified by NABL-accredited laboratory. PMI and chemical analysis 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 Bolts, Cupro Nickel 70/30 Nuts, 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 Bolts
Cupro Nickel 70/30 Nuts
Cupro Nickel 70/30 Washers
Cupro Nickel 70/30 Studs
Cupro Nickel 70/30 Threaded Rods

Technical Data

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

Cupro Nickel 70/30 Screws are available in metric M6–M100 and inch ¼″–4″ as standard. Per DIN 912 (socket head cap), DIN 963 (slotted countersunk), ISO 4762 (hex socket). Custom lengths in 5mm increments. Inch dimensions available per ASME B18.3 and B18.6.3.

Socket Head Cap Screw Dimensions - Metric (DIN 912 / ISO 4762)

Size (M)Pitch (mm)Head Dia (mm)Head Ht (mm)Hex Socket (mm)Min L (mm)Max L (mm)
M30.55.53.02.5650
M40.77.04.03.0860
M50.88.55.04.01070
M61.010.06.05.01280
M81.2513.08.06.016100
M101.516.010.08.020120
M121.7518.012.010.025150
M162.024.016.014.030200
M202.530.020.017.035250
M243.036.024.019.040300
M303.545.030.022.050400
M364.054.036.027.060500
M424.563.042.032.070600
M485.072.048.036.080700

Dimensional & Material Standards

StandardCoversThread
DIN 912Socket head cap screwsMetric
DIN 963Slotted countersunk screwsMetric
ISO 4762Hex socket screwsMetric
ASME B18.3Socket cap screwsUNC/UNF
ASME B18.6.3Machine screwsUNC/UNF
Material StandardRequirement
ASTM B151Bar/rod - UNS C71500
ASTM B151MMetric bar/rod
EN 12163Rod for general purposes
EN 10204 3.1Mill test certificate
EN 10204 3.2TPI-witnessed MTC

Material Chemistry

Cupro Nickel 70/30 Chemical Composition

Cupro Nickel 70/30 Screws 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)65.0-70.0%
Nickel (Ni) incl. Cobalt29.0-33.0%
Iron (Fe)0.4-1.0%
Manganese (Mn)1.0% max
Zinc (Zn)1.0% max
Lead (Pb)0.05% max
Phosphorus (P)0.02% max
Other Elements0.5% max (total)
? All heats verified by NABL-accredited spectrometry. PMI and full chemical analysis available on request.

Why Cupro Nickel 70/30 Alloy Composition Matters for Screws

Nickel (29–33%) — Seawater Corrosion Resistance
The high nickel content in Cupro Nickel 70/30 screws provides outstanding resistance to seawater corrosion, including resistance to biofouling and stress corrosion cracking, making them ideal for marine fastener applications.
Iron & Manganese — Erosion & Impingement Resistance
Iron and manganese additions improve the alloy’s resistance to erosion and impingement attack from fast-flowing seawater, ensuring long service life for screws in piping and condenser systems.
Copper Base — Antimicrobial & Non-Magnetic
The copper-rich matrix imparts natural antimicrobial properties and ensures the screws remain non-magnetic, which is essential for sensitive marine and naval equipment.

Fastener Performance

Cupro Nickel 70/30 Screws Mechanical Properties & Torque Reference

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

Screw SizeDry (Nm)Lubricated (Nm)Clamp Load (kN)
M66.55.24.5
M816138.5
M10322513.5
M12564519.5
M1613510832.5
M2026521251.5
M2446036874.5
?? Anti-galling: Use molybdenum-based or marine-grade anti-seize. Lubricated values assume K=0.16. Avoid copper-based anti-seize in galvanic-sensitive assemblies.

Industry Applications

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

Cupro Nickel 70/30 Screws 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 screws are the preferred fasteners for hull fittings, deck hardware, and seawater piping systems in naval and commercial vessels. Their resistance to seawater corrosion and biofouling ensures long-term reliability in shipboard environments.
Used for securing tube sheets, pump assemblies, and intake screens in desalination plants and water treatment facilities, Cupro Nickel 70/30 screws withstand brine, chlorinated water, and fluctuating temperatures without loss of mechanical integrity.
Ideal for tube-to-tube sheet connections, channel covers, and baffle plates in heat exchangers and condensers handling seawater or brackish water. The alloy’s resistance to impingement attack prevents premature fastener failure.
Cupro Nickel 70/30 screws are specified for splash zone structures, riser clamps, and cable tray supports on offshore platforms, where resistance to marine atmosphere and salt spray is essential for safety and longevity.

Cupro Nickel 70/30 Screws Standards & International Certifications

Cupro Nickel 70/30 Screws 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 912 DIN 913 DIN 914 DIN 915 DIN 916 ISO 4762 ISO 10642 ASME B18.3 EN ISO 4762 IS 1367
Certifications
ISO 9001:2015NABL LabPED 2014/68/EUMTC 3.1 / 3.2

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

Partner with RealBolt — India’s leading manufacturer of certified Cupro Nickel 70/30 Screws — 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
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Answers for Buyers

Cupro Nickel 70/30 Screws — Frequently Asked Questions

Browse expert answers to common questions about Cupro Nickel 70/30 Screws 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 screws selection and pricing.
Cupro Nickel 70/30 screws are available to DIN 912 (socket head cap), DIN 963 (slotted countersunk), ISO 4762, and ASME B18.3/B18.6.3 (inch socket and machine screws). Custom thread forms (BSW, BSF, Whitworth, BSPP) and non-standard lengths are available on request with a typical lead time of 2-3 weeks.
Use marine-grade molybdenum-based anti-seize or nickel-graphite anti-seize for Cupro Nickel 70/30 screws, especially in submerged or galvanic environments. Apply to threads and bearing surfaces. Avoid copper-based anti-seize if the screws are in contact with aluminum or stainless steel to prevent galvanic corrosion.
Yes – Cupro Nickel 70/30 screws are specifically engineered for continuous immersion in seawater and brine. They resist pitting, crevice corrosion, and biofouling, making them ideal for marine, desalination, and offshore applications without the need for additional coatings.
No formal MOQ for standard metric and inch sizes (M6-M24) held ex-stock – we supply from single pieces for urgent repairs. Custom sizes or special threads have an MOQ of 10 kg. Bulk 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