Duplex Steel S31803 S32205 Seamless Welded Pipe High Strength Anti-Corrosion ASTM A790

Duplex Steel S31803 S32205 Seamless Welded Pipe High Strength Anti-Corrosion ASTM A790

1. Product Description 

Duplex stainless steel pipe is a corrosion-resistant alloy (CRA) tubular product manufactured to stringent metallurgical and dimensional standards. Its dual-phase structure is achieved through precise chemical composition control and a solution-annealing heat treatment process. The pipe is available in seamless (SMLS) and welded (ERW, EFW, or SAWL) forms, with weld seam quality comparable to the base metal when properly processed. All products are subject to full traceability from melting to final delivery, with material test certificates (MTC) per EN 10204 3.1 or 3.2. The pipe is typically supplied in random lengths or custom-cut lengths, with beveled ends for field welding.

2. Product Applications

In addition to the well-known process piping and marine services, duplex pipes are essential in the following specific applications where quality and reliability are paramount:

• High-pressure gas injection lines – requiring full-penetration welds and 100% radiographic inspection.

• Firewater ring mains on offshore platforms – demanding impact toughness at low ambient temperatures.

• Chemical tanker piping systems – handling cargoes with varying corrosivity, requiring frequent cleaning and inspection.

• Geothermal energy production – resistant to high-temperature brine with dissolved H₂S and CO₂.

• Hydrofluoric acid alkylation units – where high-alloy content provides necessary resistance.

• Nuclear power plant auxiliary cooling water – requiring strict ferrite control and minimum intermetallic phases.

​3. Product Advantages 

• Full traceability and certified quality – every pipe is marked with heat number and subjected to chemical and mechanical verification.

• High resistance to hydrogen-induced cracking (HIC) and sulfide stress cracking (SSC) – when supplied in the appropriate heat-treated condition and hardness-controlled (<28 HRC for sour service).

• Simplified inspection – magnetic permeability allows easy ferrite-content measurement via Feritscope, ensuring phase balance.

• Low coefficient of linear thermal expansion – approximately 30% lower than austenitic grades, reducing expansion loop requirements and stress on supports.

• Good erosion resistance in high-velocity fluids – up to 30 m/s in seawater, far exceeding copper-nickel alloys.

• Recyclable and environment-friendly – 100% scrap recyclable with lower CO₂ footprint per unit strength compared to carbon steel.

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4.​Key Specifications

FAQ

1. Are you trading company or manufacturer ? We are manufacturer ,You can see the certification.

2.How long is your delivery time? Generally it is 5-10 days if the goods are in stock. or it is 15-20 days if the goods are not in stock, it is according to quantity.

3. Do you provide samples ? is it free or extra ? Yes, we could offer the sample for free charge but need pay the cost of freight.

4. What is your terms of payment ? Payment<=1000USD, 100% in advance. Payment>=1000USD, 50% T/T in advance ,balance before shippment.