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Alloy 20 (Carpenter 20Cb-3) Studs Manufacturer & Exporter in India

Explore Alloy 20 (Carpenter 20Cb-3) Studs Manufacturer & Exporter in India manufactured for demanding industrial applications with reliable strength, corrosion resistance and compliance with international standards.
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-196

Min Temp

870

Max Temp

🌡

870

Suitable for continuous service up to approximately 870°C under typical operating conditions.

⚡

620

Typical tensile strength around 620 MPa depending on product form and heat treatment.

🛡

Very Good

Very Good corrosion resistance in a wide range of industrial environments.

⚖

8

Typical density is approximately 8.0 g/cm³.

Product Overview

What are Alloy 20 (Carpenter 20Cb-3) Studs?

Alloy 20 (Carpenter 20Cb-3) studs are high-performance austenitic stainless steel fasteners manufactured from UNS N08020 bar stock, conforming to ASTM B473. Designed for exceptional resistance to sulfuric acid, chloride stress corrosion cracking, and pitting, Alloy 20 studs are widely specified in chemical processing, pharmaceutical, and food industries where standard stainless steels fail.

The alloy’s unique composition-stabilized with columbium (niobium) and containing copper and molybdenum-delivers superior corrosion resistance in aggressive environments, especially in hot sulfuric acid and chloride-bearing solutions. Alloy 20 studs are the industry standard for flange connections, pressure vessels, and process piping in critical chemical plant applications.

Quick Specifications

MaterialAlloy 20 (Carpenter 20Cb-3)
UNS NumberN08020
DIN Number2.4660
Material StandardASTM B473
Stud Standard (Metric)DIN 976 / DIN 975
Stud Standard (Inch)ASME B16.5 / B18.31.2
Thread FormISO Metric / UNC / UNF
Diameter RangeM6-M100 / ¼"-4"
Tensile Strength551 MPa (80 ksi) min
Yield Strength241 MPa (35 ksi) min
HardnessMax 217 HB
? All material certified by NABL-accredited laboratory. PMI and intergranular corrosion test available on request.

Complete the Fastener Set

Other Alloy 20 (Carpenter 20Cb-3) Fastener Products Available from RealBolt

RealBolt also manufactures the complete Alloy 20 (Carpenter 20Cb-3) fastener range — Alloy 20 (Carpenter 20Cb-3) Bolts, Alloy 20 (Carpenter 20Cb-3) Nuts, Alloy 20 (Carpenter 20Cb-3) Screws, Alloy 20 (Carpenter 20Cb-3) Washers, Alloy 20 (Carpenter 20Cb-3) Threaded Rods — from certified bar stock per ASTM with full EN 10204 MTC 3.1/3.2 documentation and fast Mumbai dispatch.
Alloy 20 (Carpenter 20Cb-3) Bolts
Alloy 20 (Carpenter 20Cb-3) Nuts
Alloy 20 (Carpenter 20Cb-3) Screws
Alloy 20 (Carpenter 20Cb-3) Washers
Alloy 20 (Carpenter 20Cb-3) Threaded Rods

Technical Data

Alloy 20 (Carpenter 20Cb-3) Studs Dimensions, Sizes & Thread Standards

Alloy 20 (Carpenter 20Cb-3) Studs are available in metric M6–M100 and inch ¼″–4″ as standard. Per DIN 976 (metric threaded rods) / DIN 975 (full thread) / ASME B16.5 (stud bolts for flanges). Custom cut lengths available in 5mm increments. Inch dimensions per ASME B18.31.2.

Stud Bolt Dimensions - Metric (DIN 976 / DIN 975)

Size (M)Pitch (mm)Thread Length (mm)Min L (mm)Max L (mm)
M61.0Full102000
M81.25Full122000
M101.5Full162000
M121.75Full202000
M162.0Full252000
M202.5Full302000
M243.0Full402000
M303.5Full502000
M364.0Full602000
M424.5Full802000
M485.0Full1002000
M565.5Full1202000
M646.0Full1402000
M726.0Full1602000
M806.0Full1802000
M1006.0Full2003000

Dimensional & Material Standards

StandardCoversThread
DIN 976Stud bolts, full threadMetric
DIN 975Threaded rods, full threadMetric
ASME B16.5Stud bolts for flangesUNC
ASME B18.31.2Continuous thread studsUNC/UNF
ISO 898-1Mechanical propertiesMetric
Material StandardRequirement
ASTM B473Bar/rod - UNS N08020
ASTM F468Fastener mechanical
NACE MR0175Sour service =217 HB
EN 10204 3.1Mill test certificate
EN 10204 3.2TPI-witnessed MTC

Material Chemistry

Alloy 20 (Carpenter 20Cb-3) Chemical Composition

Alloy 20 (Carpenter 20Cb-3) Studs (UNS N08020) are produced from a niobium-stabilized alloy containing nickel (32–38%), chromium (19–21%), molybdenum (2–3%), and copper (3–4%) per ASTM. Niobium stabilization at 8× minimum carbon content prevents intergranular corrosion in weld zones; the Mo + Cu combination delivers sulfuric acid immunity at all concentrations.

Chemical Composition per ASTM B473

ElementComposition (%)
Nickel (Ni)32.0-38.0%
Chromium (Cr)19.0-21.0%
Iron (Fe)Balance
Copper (Cu)3.0-4.0%
Molybdenum (Mo)2.0-3.0%
Manganese (Mn)2.0% max
Silicon (Si)1.0% max
Carbon (C)0.07% max
Phosphorus (P)0.045% max
Sulfur (S)0.035% max
Niobium (Nb)8xC min-1.0% max
? All heats verified by NABL-accredited spectrometry. PMI and intergranular corrosion test available on request.

Why Alloy 20 (Carpenter 20Cb-3) Alloy Composition Matters for Studs

Cu (3–4%) — Sulfuric Acid Resistance
Copper enhances Alloy 20’s resistance to sulfuric acid, making these studs the preferred choice for acid process piping and vessel flanges where 316L fails.
Mo (2–3%) — Pitting & Crevice Protection
Molybdenum increases resistance to localized attack in chloride and acidic environments, preventing pitting under flange faces and nuts.
Nb Stabilization — Intergranular Corrosion
Niobium stabilizes Alloy 20 against sensitization, ensuring stud bolts retain corrosion resistance after welding or exposure to high temperatures.

Fastener Performance

Alloy 20 (Carpenter 20Cb-3) Studs Mechanical Properties & Torque Reference

The table below lists mechanical properties and torque reference for Alloy 20 (Carpenter 20Cb-3) Studs per ASTM. Alloy 20 (Carpenter 20Cb-3) studs achieve 620 MPa tensile strength, with hardness, yield, and elongation values verified by NABL-accredited testing and reported in the EN 10204 MTC.

Stud SizeDry (Nm)Lubricated (Nm)Clamp Load (kN)
M12625022
M1615012044
M2029523669
M2451040899
M301020816158
M3617801424228
M4228402272312
M4842203376408
?? Anti-galling: Use molybdenum-based or nickel-based anti-seize. Lubricated values assume K=0.15. Avoid copper-based anti-seize in acid service.

Industry Applications

Alloy 20 (Carpenter 20Cb-3) Studs Applications — Industries & End Uses

Alloy 20 (Carpenter 20Cb-3) Studs from RealBolt are specified across sulfuric acid plants, fertilizer production, and pharmaceutical where very good corrosion resistance and 620 MPa tensile strength are required for reliable fastener performance. Click each industry below for detailed application examples.
Alloy 20 studs are the industry standard for flange connections, vessel closures, and piping in sulfuric acid production, storage, and transfer. Their copper and molybdenum content provides unmatched resistance to acid attack and pitting, outperforming 316L and Hastelloy B2 in many applications.
Used for process piping, heat exchanger channel covers, and reactor closures where resistance to organic acids, chlorides, and cleaning chemicals is critical. Alloy 20 studs meet FDA and ASME BPE requirements for hygienic and corrosion-resistant fasteners.
Stud bolts for high-chloride brine piping, evaporator flanges, and chemical dosing systems. Alloy 20’s resistance to chloride-induced stress corrosion cracking ensures long service life in aggressive water treatment environments.
Specified for bleach plant piping, digester closures, and chemical recovery systems where mixed acid and chloride exposure rapidly degrades standard stainless steel studs.

Alloy 20 (Carpenter 20Cb-3) Studs Standards & International Certifications

Alloy 20 (Carpenter 20Cb-3) Studs 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, PMI (XRF), NACE MR0175/ISO 15156, and NABL-accredited lab reports — available on request for all orders.
Standards
DIN 938 DIN 939 DIN 976-1 ASME B18.31.2 IS 1364 IS 1367
Certifications
ISO 9001:2015NACE MR0175NABL LabPED 2014/68/EUMTC 3.1 / 3.2

Buy Alloy 20 (Carpenter 20Cb-3) Studs from India's Leading Manufacturer — Get a Competitive Quote Today

Partner with RealBolt — India’s leading manufacturer of certified Alloy 20 (Carpenter 20Cb-3) Studs — 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.
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Answers for Buyers

Alloy 20 (Carpenter 20Cb-3) Studs — Frequently Asked Questions

Browse expert answers to common questions about Alloy 20 (Carpenter 20Cb-3) Studs from RealBolt — covering ASTM B473, sulfuric acid resistance, niobium stabilization, available sizes, and EN 10204 3.1 documentation. Contact our technical team directly for project-specific guidance on Alloy 20 (Carpenter 20Cb-3) studs selection and pricing.
Alloy 20 stud bolts are available to DIN 976 (metric full thread), DIN 975 (threaded rods), ASME B16.5 (flange studs), and ASME B18.31.2 (inch continuous thread). Custom thread forms (BSW, BSF, Whitworth) and cut lengths are available on request with a typical lead time of 2-3 weeks.
Use molybdenum-based or nickel-based anti-seize compound (such as Molykote P-37 or Jet-Lube 550 Extreme) for Alloy 20 studs. Avoid copper-based anti-seize in acid service to prevent galvanic corrosion. Apply to threads and nut faces to prevent galling and reduce torque values by 20% compared to dry assembly.
Yes – Alloy 20 is specifically engineered for sulfuric acid resistance and is the preferred material for fasteners in acid process piping, storage tanks, and reactors. Its copper and molybdenum content provides superior performance over 316L and many nickel alloys in hot, concentrated sulfuric acid.
No MOQ for standard sizes (M12-M36) held in stock – we supply from single pieces for urgent maintenance. Custom sizes or cut lengths have a 10 kg minimum. Flange stud sets are supplied per 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