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Ferralium 255 Washers Manufacturer & Exporter in India

Explore Ferralium 255 Washers 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 Ferralium 255 Washers?

Ferralium 255 washers are high-performance duplex stainless steel flat washers, lock washers, and custom shapes manufactured from UNS S32550 bar or plate. This super duplex alloy contains 25% chromium, 5% nickel, 3.5% copper, and 2% molybdenum, delivering exceptional resistance to pitting, crevice, and stress corrosion cracking in aggressive chloride and acidic environments.

With a PREN (Pitting Resistance Equivalent Number) of 40+, Ferralium 255 washers outperform standard 316L and 2205 duplex in seawater, brine, and chemical process applications. They are specified for critical flange assemblies, pressure vessels, and structural connections in offshore, desalination, and chemical plants where long-term reliability is essential.

Quick Specifications

MaterialFerralium 255 (Super Duplex Stainless Steel)
UNS NumberS32550
DIN Number1.4507
Material StandardASTM A240 / ASTM A182
Washer Standard (Metric)DIN 125 / DIN 127 / DIN 9021
Washer Standard (Inch)ASME B18.22.1
FormFlat, Spring, Tab, Custom
Size RangeM6-M100 / 1/4"-4"
Tensile Strength800 MPa (116 ksi) min
Yield Strength570 MPa (83 ksi) min
HardnessMax 290 HB
? All washers supplied with full traceability and PMI verification. EN 10204 3.1/3.2 certification available.

Complete the Fastener Set

Other Ferralium 255 Fastener Products Available from RealBolt

RealBolt also manufactures the complete Ferralium 255 fastener range from certified super duplex stainless steel bar stock, including Ferralium 255 Bolts, Ferralium 255 Nuts, Ferralium 255 Screws, Ferralium 255 Studs, and Ferralium 255 Threaded Rods. All Ferralium 255 fastener types are produced to ASTM with full EN 10204 MTC 3.1/3.2 documentation.
Ferralium 255 Bolts
Ferralium 255 Nuts
Ferralium 255 Screws
Ferralium 255 Studs
Ferralium 255 Threaded Rods

Technical Data

Ferralium 255 Washers Dimensions, Sizes & Thread Standards

Ferralium 255 Washers are available in metric M6–M100 and inch ¼″–4″ as standard. Per DIN 125 (flat), DIN 127 (spring), DIN 9021 (large OD), and ASME B18.22.1. Custom OD/ID and thicknesses available. Metric and inch sizes supplied to order. All Ferralium 255 washers dimensions conform to applicable DIN, ISO, and ASME B18 standards.

Flat Washer Dimensions - Metric (DIN 125)

Size (M)Inner Ø (mm)Outer Ø (mm)Thickness (mm)
M66.4121.6
M88.4161.6
M1010.5202.0
M1213.0242.5
M1617.0303.0
M2021.0373.0
M2425.0444.0
M3031.0564.0
M3637.0665.0
M4243.0786.0
M4850.0926.0
M5658.01058.0
M6466.01158.0
M7274.013010.0
M8082.014010.0
M100104.018012.0

Dimensional & Material Standards

StandardCoversForm
DIN 125Flat washersMetric
DIN 127Spring lock washersMetric
DIN 9021Large OD washersMetric
ASME B18.22.1Plain & lock washersInch
ISO 7089Flat washersMetric
ISO 7090Chamfered washersMetric
Material StandardRequirement
ASTM A240Plate - UNS S32550
ASTM A182Forged bar - UNS S32550
EN 10204 3.1Mill test certificate
EN 10204 3.2TPI-witnessed MTC

Material Chemistry

Ferralium 255 Chemical Composition

Ferralium 255 Washers are manufactured from a high-alloy ferritic-austenitic steel containing chromium (24–26%), molybdenum (3.5–5%), and nitrogen (0.24–0.32%) per ASTM. These precise elemental limits produce PREN ≥ 40 — confirming seawater pitting immunity — and deliver the 550 MPa minimum yield strength required for NORSOK M-630 subsea qualification.

Chemical Composition per ASTM A240 / UNS S32550

ElementComposition (%)
Chromium (Cr)24.0-26.0
Nickel (Ni)4.5-6.5
Molybdenum (Mo)1.5-2.0
Copper (Cu)1.5-2.5
Nitrogen (N)0.10-0.25
Silicon (Si)1.0 max
Manganese (Mn)1.5 max
Carbon (C)0.04 max
Phosphorus (P)0.04 max
Sulphur (S)0.02 max
Iron (Fe)Balance
? All heats spectro-tested and certified by NABL-accredited laboratory. PMI available on request.

Why Ferralium 255 Alloy Composition Matters for Washers

Cr (24–26%) & Mo (1.5–2.0%) — Pitting & Crevice Resistance
The high chromium and molybdenum content gives Ferralium 255 washers a PREN >40, ensuring outstanding resistance to pitting and crevice corrosion in seawater, brine, and aggressive chemical environments.
Cu (1.5–2.5%) — Acid & Chloride Tolerance
Copper enhances resistance to sulphuric, phosphoric, and organic acids, making Ferralium 255 washers ideal for chemical process and desalination plant use.
Duplex Structure — Strength & SCC Resistance
The duplex microstructure provides high mechanical strength and excellent resistance to chloride stress corrosion cracking, outperforming austenitic stainless steels in critical bolted joints.

Fastener Performance

Ferralium 255 Washers Mechanical Properties & Torque Reference

The table below lists mechanical properties and torque reference for Ferralium 255 Washers per ASTM. Ferralium 255 washers achieve 620 MPa tensile strength, with hardness, yield, and elongation values verified by NABL-accredited testing and reported in the EN 10204 MTC.

Bolt SizeRecommended Washer OD (mm)Recommended Thickness (mm)
M12242.5
M16303.0
M20373.0
M24444.0
M30564.0
M36665.0
M42786.0
M48926.0
?? Installation: Always use Ferralium 255 washers with matching super duplex bolts/nuts for optimal corrosion resistance. Avoid mixing with carbon steel hardware.

Industry Applications

Ferralium 255 Washers Applications — Industries & End Uses

Ferralium 255 Washers from RealBolt are specified across subsea oil and gas, FPSOs, desalination, and offshore where very good corrosion resistance and 620 MPa tensile strength are required for reliable fastener performance. Click each industry below for detailed application examples.
Ferralium 255 washers are specified for flange assemblies, riser clamps, and structural joints on offshore platforms, subsea manifolds, and FPSO topsides. Their high PREN and SCC resistance ensure long-term reliability in seawater and sour gas environments.
Used in high-pressure RO vessel flanges, pump assemblies, and brine piping supports, Ferralium 255 washers prevent crevice corrosion and maintain preload in aggressive chloride-rich water and brine streams.
Washer sets for heat exchanger covers, reactor closures, and acid pipeline flanges in phosphoric, sulphuric, and nitric acid service. Ferralium 255’s copper content enhances resistance to mineral acids and mixed halide solutions.
Flat and spring washers for propeller shaft couplings, hull penetrations, and deck equipment where exposure to seawater and salt spray demands superior pitting and crevice corrosion resistance.

Ferralium 255 Washers Standards & International Certifications

Ferralium 255 Washers 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 3.2 (third-party), NACE MR0175/ISO 15156, NORSOK M-630, Charpy impact certificates, and PMI (XRF) reports — available on request for all orders.
Standards
DIN 125A DIN 126 DIN 127 DIN 128 ISO 7089 ISO 7090 ASME B18.21.1 EN ISO 7089 IS 5372 IS 1367 IS 12427
Certifications
ISO 9001:2015NACE MR0175NABL LabPED 2014/68/EUMTC 3.1 / 3.2

Buy Ferralium 255 Washers from India's Leading Manufacturer — Get a Competitive Quote Today

Partner with RealBolt — India’s leading manufacturer of certified Ferralium 255 Washers — 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

Ferralium 255 Washers — Frequently Asked Questions

Browse expert answers to common questions about Ferralium 255 Washers from RealBolt — covering PREN ≥ 40, NORSOK M-630, NACE MR0175, ASTM A182 F53/F55, sizes, and EN 10204 3.2 third-party documentation. Contact our technical team directly for project-specific guidance on Ferralium 255 washers selection and pricing.
Ferralium 255 washers are available to DIN 125 (flat), DIN 127 (spring), DIN 9021 (large OD), ISO 7089/7090, and ASME B18.22.1 (inch). Custom OD, ID, and thicknesses are available on request. All washers are manufactured from ASTM A240/A182 UNS S32550 plate or bar and supplied with EN 10204 3.1/3.2 certification.
Yes – Ferralium 255 washers are specifically designed for seawater, brine, and high-chloride environments. Their PREN >40 and duplex structure provide outstanding resistance to pitting, crevice, and stress corrosion cracking, making them ideal for offshore, desalination, and marine applications.
For best results, Ferralium 255 washers should be paired with super duplex or compatible stainless steel bolts and nuts. Avoid mixing with carbon steel or lower alloy hardware to prevent galvanic corrosion, especially in wet or immersed service.
No MOQ for standard sizes (M8-M36) held ex-stock – single pieces can be supplied for urgent maintenance. Custom sizes or special shapes may require a 5 kg minimum. Quantity price breaks are available at 50, 200, 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