Duplex & Super Duplex Tubes Supplier
High-strength corrosion-resistant tubes for heat exchangers, offshore, oil & gas, desalination and petrochemical applications
Duplex & Super Duplex Stainless Steel Tubes Supplier
DLSS supplies duplex and super duplex stainless steel tubes designed for corrosive, high-pressure and chloride-containing environments. Our tubes are widely used in heat exchangers, offshore platforms, oil & gas, petrochemical plants, desalination systems and seawater cooling applications.
Compared with standard austenitic stainless steel, duplex stainless steel provides higher strength and better resistance to chloride stress corrosion cracking, pitting and crevice corrosion. DLSS supports Duplex 2205, S31803, S32205, Super Duplex 2507 and S32750 tube solutions for demanding industrial projects.
Applications:
Offshore platforms, seawater heat exchangers, desalination systems, oil & gas processing, petrochemical plants, pressure vessels and marine cooling systems
Standards:
ASTM A789 / ASME SA789 / ASTM A790 / ASME SA790 / EN 10216-5
Materials:
Duplex 2205 / S31803 / S32205 / Super Duplex 2507 / S32750
Production Capability:
Seamless / welded / U bend / cut length / pickled or polished surface
Quality Assurance:
100% PMI, hydrostatic testing, UT / ET, PT, dimensional inspection and full EN10204 3.1 / 3.2 traceability
Duplex & Super Duplex Tube Specifications
Technical specifications for duplex stainless steel tubes used in critical corrosion-resistant applications
| Item | Specification |
|---|---|
| Product Name | Duplex & Super Duplex Stainless Steel Tubes |
| Main Grades | Duplex 2205 / S31803 / S32205 / Super Duplex 2507 / S32750 |
| Standards | ASTM A789 / ASME SA789 / ASTM A790 / ASME SA790 / EN 10216-5 |
| Tube Type | Seamless / Welded / U Bend / Heat Exchanger Tubes |
| Outside Diameter | 6 mm – 114.3 mm or customized |
| Wall Thickness | 0.5 mm – 12 mm or customized |
| Length | Fixed length / Random length / Cut length |
| Surface Finish | Pickled / Polished / Bright Annealed |
| Testing | PMI / Hydro Test / Eddy Current / UT / PT / Visual Inspection |
| Certificate | EN10204 3.1 / 3.2 / Third-party Inspection |
| Application | Heat Exchanger / Offshore / Oil & Gas / Desalination / Petrochemical |
| Delivery Time | 7–35 days depending on grade, size and quantity |
| Packing | Export wooden case / Iron frame / Seaworthy packing |
Duplex & Super Duplex Grades We Supply
Select the right duplex grade according to corrosion environment, temperature and project requirements
Duplex 2205 / S32205
A widely used duplex stainless steel grade with high strength and strong resistance to chloride stress corrosion cracking.
✓ Good resistance to chloride environments
✓ Higher strength than standard austenitic stainless steel
✓ Suitable for heat exchangers and oil & gas equipment
✓ Cost-effective duplex solution
Duplex S31803
A standard duplex stainless steel grade combining austenitic and ferritic structures for corrosion resistance and mechanical strength.
✓ High resistance to stress corrosion cracking
✓ Good pitting and crevice corrosion resistance
✓ Suitable for chemical and process industries
✓ Commonly used in tubular products
Super Duplex 2507 / S32750
A super duplex stainless steel grade designed for highly corrosive chloride-containing environments.
✓ Excellent seawater corrosion resistance
✓ High strength and durability
✓ Suitable for offshore and desalination applications
✓ Strong resistance to pitting and crevice corrosion
Custom Duplex Tube Solutions
Custom duplex tube solutions for project-specific size, testing, marking and certification requirements.
✓ Custom OD / WT / length
✓ U bend and heat exchanger tube support
✓ Third-party inspection available
✓ Special packing for export projects
Typical Applications of Duplex & Super Duplex Tubes
Built for chloride, seawater, high-pressure and corrosive industrial environments
Heat Exchanger Systems
Duplex and super duplex tubes are used in heat exchangers requiring corrosion resistance, high strength and stable long-term performance.
✓ Suitable for aggressive process media
✓ Strong resistance to chloride corrosion
✓ Reliable tube-to-tubesheet performance
✓ Long service life
Offshore & Marine
Duplex stainless steel tubes are widely used in offshore platforms, marine systems and seawater cooling equipment.
✓ Seawater corrosion resistance
✓ Chloride stress corrosion cracking resistance
✓ High mechanical strength
✓ Suitable for offshore project certification
Oil & Gas / Petrochemical
Duplex tubes are suitable for refineries, gas processing plants, chemical plants and pressure systems exposed to corrosive media.
✓ Good resistance to acid and chloride environments
✓ Full material traceability
✓ Suitable for high-pressure process systems
✓ Third-party inspection support
Desalination & Seawater Systems
Super duplex tubes are suitable for desalination plants, seawater cooling systems and marine heat exchangers.
✓ Excellent pitting resistance
✓ Strong seawater durability
✓ Long maintenance cycle
✓ Suitable for Middle East seawater projects
Duplex & Super Duplex Tube Project Cases
Proven supply experience for offshore, heat exchanger, desalination and petrochemical projects
Duplex 2205 Tubes for Offshore Heat Exchanger Project
Material: Duplex 2205 / S32205 Standard: ASTM A789 Application: Offshore Heat Exchanger Inspection: PMI / Hydro Test / UT ✓ Chloride corrosion resistance ✓ Full MTC traceability ✓ Third-party inspection support ✓ Strong seaworthy packing
Super Duplex 2507 Tubes for Seawater Cooling System
Material: Super Duplex 2507 / S32750 Application: Desalination / Seawater Cooling Inspection: PMI / PT / Hydro Test ✓ Excellent seawater resistance ✓ Strong pitting corrosion resistance ✓ Suitable for marine environment ✓ Export packing for long-distance shipment
Duplex Tubes for Petrochemical Processing Equipment
Material: S31803 / S32205 Application: Chemical Processing / Heat Exchanger Inspection: EN10204 3.1 / PMI / Dimensional Inspection ✓ Strong corrosion resistance ✓ Stable dimensional tolerance ✓ Full certification support ✓ On-time project delivery
Send your specifications – we will respond within 24 hours
Customized Duplex Tube Solutions For Your Project
Flexible support for heat exchanger manufacturers, EPC contractors, stockists and project buyers
For Heat Exchanger Manufacturers
Stable tube quality, precise tolerance and reliable delivery for your heat exchanger production.
✓ Tight OD & WT tolerance
✓ U bend tube support
✓ Custom cut length
✓ Full inspection before shipment
For EPC Contractors & Project Buyers
Technical confirmation, documentation and delivery support for critical project requirements.
✓ Fast RFQ response
✓ Third-party inspection
✓ Full export documentation
✓ Project delivery tracking
For Stockists & Distributors
Flexible MOQ and stable supply to support your local stock and market development.
✓ Flexible quantity support
✓ Common duplex grades
✓ Export packing
✓ Custom marking available
Strict Quality Control For Duplex & Super Duplex Tubes
Every tube is inspected to ensure material accuracy, corrosion performance and dimensional reliability
Material & Dimensional Inspection
PMI and spectrometer testing ensure correct material grade and dimensional accuracy.
Ring Gauge Inspection
Ensures dimensional accuracy and proper tube fitting.
Hydrostatic Pressure Testing
Verifies strength and leak-proof performance under pressure.
Penetrant Testing (PT)
Detects surface cracks and defects effectively.
Borescope Inspection
Ensures internal surface quality and detects inner defects.
Visual Inspection
Checks external surface quality and appearance.
All tubes are inspected according to ASTM, ASME, EN standards and customer requirements.
Frequently Asked Questions
Common questions about duplex and super duplex stainless steel tubes
Duplex stainless steel combines austenitic and ferritic structures, offering high strength and corrosion resistance. Super duplex stainless steel contains higher chromium, molybdenum and nitrogen levels, giving stronger resistance to pitting, crevice corrosion and seawater environments.
Common grades include Duplex 2205, S31803, S32205, Super Duplex 2507 and S32750. The right grade depends on corrosion environment, pressure, temperature and project requirements.
Common standards include ASTM A789 / ASME SA789 for duplex stainless steel tubing and ASTM A790 / ASME SA790 for duplex stainless steel pipe. EN 10216-5 is also used for stainless steel seamless tubes in European projects.
Yes. Duplex and super duplex stainless steel tubes are widely used in seawater cooling, offshore, marine and desalination systems because of their resistance to chloride corrosion and high mechanical strength.
Yes. DLSS supports third-party inspection by SGS, BV, TUV, DNV, ABS, LR and other inspection agencies according to project requirements.
We can provide EN10204 3.1 / 3.2 certificates, MTC, PMI reports, hydro test reports, dimensional inspection reports and third-party inspection documents.
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Read MoreNeed Duplex Tubes For Your Next Project?
Send us your material grade, tube size, standard, quantity or project drawings.
Our technical team will help you confirm the suitable duplex or super duplex tube solution for your working environment.
Fast technical response within 24 hours