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Rajgranth Metal & AlloysRAJGRANTH
Duplex

Duplex / Super Duplex

A duplex microstructure delivers what austenitics cannot: high strength and high chloride resistance at the same time. 2205 (S31803/S32205) is the workhorse; the super duplex grades 2507 (S32750) and Zeron-type S32760 push PREN above 40 for seawater and sour service. The strength advantage often allows a thinner wall, which recovers much of the cost premium on a large project.

Designations
UNS S31803 / S32205 / S32550 / S32750 / S32760EN 1.4462 / 1.4507 / 1.4501AISI F51 / F60 / F53 / F55JIS SUS329J3LGB S22053X2CrNiMoN22-5-3 / X2CrNiMoCuWN25-7-4

Properties

Duplex
PREN
41

Pitting resistance equivalent. Higher resists chlorides better.

Relative cost
2.60×

Indexed to 304. Indicative, for specification triage.

Max service temp
300 °C
Magnetic
Partially
Weldability
Procedure required
Machinability
Difficult
01Product description

Duplex and Super Duplex Stainless Steel: manufacturer, stockholder and exporter in Mumbai, India

Rajgranth Metal & Alloys manufactures, stocks, supplies and exports Duplex and Super Duplex Stainless Steel in 12 product forms from Mumbai. Roughly equal austenite and ferrite. Around twice the yield strength of 316L. Rajgranth Metal & Alloys has been trading since 1980, is self-funded and debt-free, and despatches most orders from its Mumbai stockyard within two days.

About Duplex and Super Duplex Stainless Steel

A duplex microstructure delivers what austenitics cannot: high strength and high chloride resistance at the same time. 2205 (S31803/S32205) is the workhorse; the super duplex grades 2507 (S32750) and Zeron-type S32760 push PREN above 40 for seawater and sour service. The strength advantage often allows a thinner wall, which recovers much of the cost premium on a large project.

Designations and equivalents

Duplex and Super Duplex Stainless Steel is also designated UNS S31803 / S32205 / S32550 / S32750 / S32760, EN 1.4462 / 1.4507 / 1.4501, AISI F51 / F60 / F53 / F55, JIS SUS329J3L, GB S22053 and Werkstoff X2CrNiMoN22-5-3 / X2CrNiMoCuWN25-7-4.

Strengths and limitations

Strengths: Yield strength roughly double that of 316L, allowing thinner sections, Excellent resistance to chloride stress corrosion cracking, Super duplex PREN above 40 for seawater service and Good resistance to erosion and cavitation. Limitations: Hard upper service limit near 300 degrees C — 475 degrees C embrittlement, Welding requires controlled heat input to maintain phase balance, Ferromagnetic, which rules it out where magnetic permeability matters and Machining is demanding and tool wear is high.

Applications

offshore and subsea piping, seawater cooling and desalination, chemical tankers and cargo systems, sour gas service and pressure vessels where weight matters. Typical industries: oil & gas, marine & shipbuilding, chemical, petrochemical and power & energy. We supply across India and export to markets in the Middle East, Africa, Europe, Asia, North America and South America.

Buy Duplex / Super Duplex from Rajgranth

Material is supplied with documentation, tested in house across 18 listed testing facilities, and covered by our ISO 9001:2015 quality management system. Rajgranth Metal & Alloys has been trading since 1980, is self-funded and debt-free, and despatches most orders from its Mumbai stockyard within two days.

Also searched as

  • duplex and Super Duplex Stainless Steel manufacturer in Mumbai
  • duplex and Super Duplex Stainless Steel stockist
  • duplex and Super Duplex Stainless Steel supplier in India
  • duplex and Super Duplex Stainless Steel exporter

Chosen for

04
  • Yield strength roughly double that of 316L, allowing thinner sections
  • Excellent resistance to chloride stress corrosion cracking
  • Super duplex PREN above 40 for seawater service
  • Good resistance to erosion and cavitation

Where it fails

04
  • Hard upper service limit near 300 degrees C — 475 degrees C embrittlement
  • Welding requires controlled heat input to maintain phase balance
  • Ferromagnetic, which rules it out where magnetic permeability matters
  • Machining is demanding and tool wear is high
01Available in

Duplex / Super Duplex product forms

Each combination is a page with its own dimensional range, finishes and standards.

Applications

05
  • Offshore and subsea piping
  • Seawater cooling and desalination
  • Chemical tankers and cargo systems
  • Sour gas service
  • Pressure vessels where weight matters

Industries

09

FAQ

04

Selecting a grade

What is the difference between 304 and 316?
316 contains 2 to 3 percent molybdenum, which 304 does not. That improves resistance to pitting and crevice corrosion in chloride environments, which is why 316 suits marine, chemical and coastal service. For dry indoor, food and general water use, 304 performs well at lower cost.
What is duplex and super duplex stainless steel?
A duplex microstructure is roughly half austenite and half ferrite, giving about double the yield strength of 316L together with much better resistance to chloride stress corrosion cracking. Super duplex (for example 2507) pushes corrosion resistance further for seawater and sour service. The main limit is a maximum service temperature near 300 degrees Celsius.
What does PREN mean?
PREN is the Pitting Resistance Equivalent Number: percent chromium plus 3.3 times percent molybdenum plus 16 times percent nitrogen. Higher means better resistance to pitting in chlorides. It is a ranking figure, not a substitute for assessing a specific service condition.
Which grade should I choose?
It depends on the medium, temperature and pressure the material will see. Our grade pages and the grade comparator set out composition, corrosion behaviour and limitations side by side; if you tell us the service conditions, we will tell you what we would specify.

Need Duplex / Super Duplex?

Send the form, size, quantity and standard. We will confirm what is in stock and quote.

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