Duplex & Super Duplex | High Strength | Chloride Resistance

Duplex & Super Duplex Steel Products Supplier, Stockist & Exporter

SteelNix supplies duplex and super duplex steel pipes and tubes, round bars, sheets and plates for offshore, marine, desalination, chemical, oil and gas and other chloride-rich environments.

MTC support available ASTM, ASME, EN and project standards Standard and project-based supply
Material overview

What Are Duplex and Super Duplex Steels?

Duplex stainless steels combine ferritic and austenitic microstructures. This structure provides higher yield strength than common 300-series stainless steels and improves resistance to chloride stress-corrosion cracking.

Super duplex grades contain higher alloying additions for stronger pitting, crevice-corrosion and chloride performance. They are selected for seawater, brine, offshore and severe process environments where both strength and corrosion resistance are critical.

Selection guide

Choose Duplex & Super Duplex Steel by Application

This guide is an initial reference. Final material selection must follow the applicable standard, design conditions, temperature, medium, fabrication route and inspection requirements.

General duplex

Process & structural service

Balanced strength and corrosion resistance for process, marine and structural applications.

Typical starting grades: UNS S31803, S32205
Super duplex

Seawater & severe chloride

For high chloride, seawater and severe pitting or crevice-corrosion exposure.

Typical starting grades: UNS S32750, S32760
Offshore systems

Subsea & topside

For piping, manifolds, fasteners, valves, pumps and exposed equipment.

Typical starting grades: F51, F60, F53, F55
Desalination

Brine & seawater lines

For seawater intake, high-salinity systems, evaporators and heat exchangers.

Typical starting grades: S32205, S32750, S32760
Chemical processing

Acid and chloride media

For vessels, piping and equipment exposed to aggressive process conditions.

Typical starting grades: S31803, S32205, S31260
Fabricated equipment

Vessels & exchangers

For welded pressure equipment and heat-transfer systems under controlled fabrication.

Typical starting grades: Project-specified duplex grades
Grade families

Popular Duplex & Super Duplex Steel Grades and Specifications

Review the principal material families used for common industrial, pressure, fabrication and engineering requirements.

DUP

Standard Duplex

Balanced corrosion resistance and strength for process and chloride service.

S31803S32205F51F60
SDX

Super Duplex

Higher pitting resistance and strength for seawater and aggressive chloride environments.

S32750S32760F53F55
SPEC

Special Duplex

Special chemistry for demanding process, marine and project conditions.

S31260S32900S32550
FORM

Product Forms

Multiple forms for fabrication, pressure service and machining.

PipesTubesRound BarsPlatesSheets
Duplex & Super Duplex Steel — General Supply Details
CategoryAvailable Range
Product FormsPipes, tubes, round bars, forged bars, sheets and plates
Common Duplex GradesUNS S31803, UNS S32205, F51, F60 and UNS S31260
Common Super Duplex GradesUNS S32750, UNS S32760, F53 and F55
Typical ApplicationsOffshore, marine, desalination, chemical processing, oil and gas and heat exchangers
Quality DocumentsMTC, PMI, dimensional inspection and corrosion-testing support as applicable
RFQ DetailsProduct form, UNS or ASTM grade, size, thickness, quantity, delivery location and inspection scope
Technical properties and availability vary by grade, product form, size, heat treatment, applicable standard and order condition. Verify final values against the governing material specification before procurement.
Industrial applications

Industries We Serve

SteelNix supports project, maintenance, fabrication, OEM, stock and export enquiries across demanding industrial sectors.

01

Offshore

Topside, subsea, manifolds, piping and exposed components.

02

Marine

Seawater lines, ship systems and corrosion-resistant hardware.

03

Desalination

Intake, brine, evaporator and high-chloride systems.

04

Oil & Gas

Process piping, valves, pumps and sour or chloride service.

05

Chemical Plants

Vessels, process equipment and corrosive-fluid handling.

06

Pulp & Paper

Digesters, bleaching and chloride-bearing process systems.

07

Water Treatment

Filtration, brine and aggressive water-service equipment.

08

Power & FGD

Flue-gas desulphurisation and corrosion-critical plant systems.

Procurement support

Why Choose SteelNix?

The page is designed to help buyers move from product and grade research to a technically complete quotation request.

01

Broad Product Range

Compare the main product forms and grade families from one professional category hub.

02

Application Guidance

Use practical service-based information to narrow the initial grade selection.

03

Documentation Support

MTC and inspection requirements can be discussed before order finalisation.

04

Clear RFQ Process

Complete technical details help reduce delays and improve quotation accuracy.

Faster quotation

What to Include in Your Enquiry

Complete technical information reduces follow-up questions and helps the correct product, grade, standard and delivery requirement be reviewed.

Product formMaterial gradeSize or diameterThickness or scheduleLength and quantityApplicable standardDelivery locationTesting / MTC requirement
Buyer questions

Frequently Asked Questions

Helpful answers for buyers comparing duplex & super duplex steel products and specifications.

What is the difference between duplex and super duplex steel?
Duplex steel offers a strong balance of strength and corrosion resistance. Super duplex has higher alloy content, pitting resistance and strength for more aggressive chloride and seawater environments.
Which duplex grades does SteelNix supply?
Common grades include UNS S31803, UNS S32205, F51, F60 and UNS S31260, depending on product form and availability.
Which super duplex grades are available?
Common super duplex grades include UNS S32750, UNS S32760, F53 and F55.
Where are duplex and super duplex products used?
Typical uses include offshore, marine, desalination, chemical processing, oil and gas, heat exchangers, valves, pumps and pressure equipment.
Can SteelNix provide PMI and MTC?
MTC, PMI and inspection support can be arranged according to product, quantity, project specification and order terms.
What information is needed for pricing?
Provide the product form, grade, size, wall thickness or plate thickness, quantity, standard, delivery location and testing or inspection scope.
Explore more materials

Related Steel Product Families

Review other SteelNix material categories when the project requires a different balance of cost, strength, corrosion or temperature performance.

Need Duplex & Super Duplex Steel Products for Your Project?

Send the product form, grade, dimensions, quantity, standard, delivery location and required documents. SteelNix can review material availability and quotation details.