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SS 420 Bolts Manufacturer & Exporter in India

Explore SS 420 Bolts 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 SS 420 Bolts?

SS 420 bolts are high-strength martensitic stainless steel fasteners manufactured from UNS S42000 bar stock conforming to ASTM A276 and ASTM F593. With a minimum chromium content of 12% and the ability to be heat treated to high hardness, SS 420 bolts offer excellent mechanical strength, moderate corrosion resistance, and superior wear resistance compared to austenitic grades.

These bolts are widely specified for applications requiring a combination of strength and moderate corrosion resistance, such as pump shafts, valve stems, and high-load mechanical assemblies. SS 420 bolts are magnetic, can be polished to a mirror finish, and are suitable for service temperatures up to 650°C in non-chloride environments.

Quick Specifications

MaterialStainless Steel 420
UNS NumberS42000
DIN Number1.4021
Material StandardASTM A276 / ASTM F593
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 Strength700-950 MPa (min, heat treated)
Yield Strength= 520 MPa
HardnessUp to 50 HRC (heat treated)
? All material certified by NABL-accredited laboratory. PMI and hardness survey available on request.

Complete the Fastener Set

Other SS 420 Fastener Products Available from RealBolt

RealBolt also manufactures the complete SS 420 fastener range from certified stainless steel bar stock, including SS 420 Nuts, SS 420 Screws, SS 420 Washers, SS 420 Studs, and SS 420 Threaded Rods. All SS 420 fastener types are produced to ASTM with full EN 10204 MTC 3.1/3.2 documentation.
SS 420 Nuts
SS 420 Screws
SS 420 Washers
SS 420 Studs
SS 420 Threaded Rods

Technical Data

SS 420 Bolts Dimensions, Sizes & Thread Standards

SS 420 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 SS 420 bolts dimensions are verified against applicable DIN, ISO, and ASME

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
Material StandardRequirement
ASTM A276Bar/rod - UNS S42000
ASTM F593Fastener mechanical
EN 10204 3.1Mill test certificate
EN 10204 3.2TPI-witnessed MTC

Material Chemistry

SS 420 Chemical Composition

SS 420 Bolts are manufactured from an iron-chromium-nickel alloy with chromium (16–26%), nickel (8–28%), and grade-specific molybdenum additions per ASTM and ASTM A193/A194. Chromium content governs the self-healing passive oxide film; molybdenum (2–6%) enhances chloride pitting resistance; and carbon content determines sensitization risk in welded assemblies.

Chemical Composition per ASTM A276

ElementComposition (%)
Carbon (C)0.15% max
Chromium (Cr)12.0-14.0%
Nickel (Ni)0.75% max
Manganese (Mn)1.0% max
Silicon (Si)1.0% max
Phosphorus (P)0.04% max
Sulfur (S)0.03% max
Molybdenum (Mo)0.60% max
Iron (Fe)Balance
? All heats verified by NABL-accredited spectrometry. PMI and hardness survey available on request.

Why SS 420 Alloy Composition Matters for Bolts

High Carbon — Superior Hardness
The elevated carbon content in SS 420 enables heat treatment to high hardness (up to 50 HRC), making these bolts ideal for wear-prone and high-load applications.
12–14% Chromium — Corrosion Resistance
Chromium provides a passive oxide layer, giving SS 420 bolts moderate resistance to atmospheric and mild chemical corrosion, suitable for non-chloride, non-marine environments.
Martensitic Structure — Magnetic & Machinable
SS 420 bolts are magnetic and can be machined and polished to a mirror finish, making them suitable for decorative and functional mechanical assemblies.

Fastener Performance

SS 420 Bolts Mechanical Properties & Torque Reference

The table below lists mechanical properties and torque reference for SS 420 Bolts per ASTM. SS 420 bolts achieve 620 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)
M12957635
M1623018485
M20470376140
M24820656210
M3016401312335
M3628502280485
M4245503640670
M4867505400900
?? Anti-galling: Use molybdenum-based anti-seize (Molykote 1000). Lubricated values assume K=0.16. Avoid assembly at high speeds to prevent thread galling.

Industry Applications

SS 420 Bolts Applications — Industries & End Uses

SS 420 Bolts from RealBolt are specified across food and dairy, pharmaceutical, marine, chemical processing, and oil and gas where very good corrosion resistance and 620 MPa tensile strength are required for reliable fastener performance. Click each industry below for detailed application examples.
SS 420 bolts are used for turbine casing bolts, boiler manway covers, and high-strength fasteners in power plants where moderate corrosion resistance and high hardness are required for long-term service at elevated temperatures.
Hex bolts and stud bolts for pump shafts, valve stems, and hydraulic cylinder assemblies where wear resistance and strength are critical, especially in mildly corrosive or abrasive environments.
SS 420 bolts are specified for engine components, transmission assemblies, and high-load mechanical joints in trucks, earthmovers, and industrial machinery due to their superior hardness and fatigue resistance.
Used for fasteners in food processing equipment, packaging machinery, and conveyor systems where moderate corrosion resistance and the ability to polish to a hygienic finish are required.

SS 420 Bolts Standards & International Certifications

SS 420 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, hardness test certificate, ISO 3506 material certification, and NABL-accredited lab reports — available on request for all orders.
Standards
DIN 931 DIN 933 ISO 4014 ISO 4017 ASME B18.2.1 EN ISO 4014 EN ISO 4017 IS 1364 IS 1367
Certifications
ISO 9001:2015PED 2014/68/EUNABL LabMTC 3.1 / 3.2

Buy SS 420 Bolts from India's Leading Manufacturer — Get a Competitive Quote Today

Partner with RealBolt — India’s leading manufacturer of certified SS 420 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
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Answers for Buyers

SS 420 Bolts — Frequently Asked Questions

Browse expert answers to common questions about SS 420 Bolts from RealBolt — covering ASTM A193/A194 grades, chloride resistance, temperature limits, sensitization, sizes, and MTC documentation. Contact our technical team directly for project-specific guidance on SS 420 bolts selection and pricing.
SS 420 bolts are available to DIN 931 (hex bolts, partial thread), DIN 933 (full thread), ISO 4014/4017, and ASME B18.2.1 (inch hex and heavy hex). Stud bolts can be supplied to ASME B16.5 for flange applications. Custom thread forms (BSW, BSF, Whitworth) are available on request.
Use a molybdenum-based anti-seize compound (such as Molykote 1000 or Loctite LB 8012) on SS 420 bolts to prevent galling and seizing during assembly. Avoid copper-based anti-seize to prevent galvanic corrosion. Lubricated torque values should be reduced by 20% compared to dry assembly.
No – SS 420 bolts are not recommended for marine or chloride-rich environments due to their moderate corrosion resistance. For such applications, use SS 316 or duplex stainless steel bolts. SS 420 is best suited for mildly corrosive, non-chloride, or dry environments.
Standard sizes (M8-M36) are available ex-stock with no formal MOQ – single pieces can be supplied for urgent requirements. Custom sizes or heat-treated bolts may require a 10 kg minimum. Price breaks are available at 50, 200, and 500 pieces.

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