Duplex Steel Fittings | UNS S31803 Manufacturer

Name: Duplex Steel Fittings
Brand: Solitaire Overseas

Engineered for Strength. Trusted for Performance.

At Solitaire Overseas, we bring over two decades of metallurgical expertise and global supply experience to the manufacturing of Duplex Steel Fittings, particularly in the UNS S31803 (Duplex 2205) grade. As an ISO 9001:2015 certified company with a proven track record across 60+ countries, we are recognized by EPC contractors, petrochemical majors, and offshore clients for delivering consistent, high-performance duplex stainless steel fittings—backed by full traceability and third-party testing.

Our Duplex Pipe Fittings are engineered with a balanced austenitic-ferritic microstructure, providing exceptional mechanical strength, resistance to chloride-induced corrosion, and long-term structural stability under high-pressure and aggressive media. Each fitting is produced in strict accordance with ASTM A815, ASME B16.9, and MSS-SP-43, ensuring compliance with global piping standards.

What sets us apart is our deep technical understanding of application-specific requirements. From sub-zero marine pipelines to superheated refinery loops, our experts help clients select fittings that ensure operational reliability and regulatory compliance. Every batch is subjected to Positive Material Identification (PMI), hydro tests, and ultrasonic inspections—reinforcing our commitment to quality and safety.

When you choose Solitaire Overseas, you're not just buying a product—you're investing in a reputation built on precision, performance, and engineering integrity.

What Are Duplex Steel Fittings?

Duplex Steel Fittings are precision-engineered pipe components made from duplex stainless steel—a material known for its dual-phase microstructure combining both austenitic and ferritic stainless steels. This unique structure offers a remarkable balance of high tensile strength, superior corrosion resistance, and excellent stress corrosion cracking resistance, especially in chloride-rich and high-pressure environments.

One of the most commonly used grades for these fittings is UNS S31803 (also known as Duplex 2205). It contains chromium, molybdenum, and nitrogen in optimized proportions, making it significantly stronger than conventional 304 or 316 stainless steel while being more cost-effective than super duplex alloys. Duplex pipe fittings are typically used in industries such as oil & gas, desalination, petrochemicals, marine engineering, and chemical processing—where both mechanical durability and corrosion resistance are critical.

At Solitaire Overseas, we ensure that every Duplex Stainless Steel Fitting we manufacture adheres to international standards like ASTM A815 and ASME B16.9, backed by certified testing and documentation. With our deep industry experience, global compliance knowledge, and metallurgical insight, we help clients select the right duplex fittings for their project’s technical and regulatory requirements—ensuring performance, safety, and long-term value.

Types of Duplex Stainless Steel Fittings We Offer

At Solitaire Overseas, we specialize in manufacturing and supplying a comprehensive range of Duplex Stainless Steel Fittings, precisely engineered to withstand extreme environments where both corrosion resistance and mechanical strength are critical. Our fittings are manufactured from premium grades such as UNS S31803 (Duplex 2205) and conform to international standards including ASTM A815, ASME B16.9, and MSS-SP-43.

With years of hands-on industry experience and metallurgical expertise, we offer duplex fittings in multiple configurations, sizes, and pressure classes, tailored to suit complex piping requirements across industries like oil & gas, petrochemicals, power generation, and marine systems.

Common Types of Duplex Steel Fittings Available:

Fitting Type	Description
Duplex Elbows (45° / 90° / 180°)	Used to change the direction of flow in piping systems, ideal for high-pressure and corrosive lines.
Duplex Tees (Equal / Reducing)	Designed to combine or divide fluid flow while maintaining system pressure integrity.
Duplex Reducers (Concentric / Eccentric)	Facilitate transitions between different pipe sizes while maintaining flow efficiency.
Duplex Caps	Seal the end of pipelines and vessels, offering pressure containment and corrosion resistance.
Duplex Stub Ends	Used with lap joint flanges, commonly in systems that require frequent dismantling.
Duplex Cross Fittings	Allow the connection of four pipe sections in a cross-like configuration, used in special installations.
Duplex Couplings & Unions	Ensure secure and leak-proof connections in small-bore piping systems.

All fittings are available in seamless, welded, and fabricated forms, with custom sizes, wall thicknesses (SCH10 to SCH160), and end connections (beveled, threaded, or plain end).

Our in-house quality control processes, third-party inspection options (SGS, TUV, BV), and traceable documentation (EN 10204 3.1/3.2) ensure that every duplex fitting you receive from Solitaire Overseas is fit-for-purpose, globally compliant, and performance-assured.

Technical Specifications – Duplex Pipe Fittings

At Solitaire Overseas, our Duplex Pipe Fittings are manufactured with precision engineering and stringent quality control to meet the complex demands of industries operating in corrosive, high-pressure, and high-temperature environments. Fabricated using premium-grade Duplex Stainless Steel (UNS S31803 / S32205), these fittings deliver superior strength, extended durability, and outstanding resistance to chloride-induced corrosion.

We strictly adhere to globally recognized standards such as ASTM A815, ASME B16.9, MSS-SP-43, and EN 10253, ensuring dimensional accuracy, pressure compatibility, and seamless integration into pipeline systems across the oil & gas, petrochemical, chemical processing, marine, and power generation sectors.

Duplex Pipe Fittings – Standard Technical Specifications:

Parameter	Specification Details
Material Grades	Duplex Stainless Steel UNS S31803 / S32205
Manufacturing Standards	ASTM A815, ASME B16.9, MSS-SP-43, EN 10253
Size Range	½” NB to 24” NB (Seamless), up to 48” NB (Welded)
Thickness (Schedule)	SCH 10, SCH 40, SCH 80, SCH 160, XXS
Connection Types	Butt-weld, Socket Weld, Threaded
Form Types	Elbow, Tee, Reducer, Cap, Stub End, Cross
Pressure Ratings	Up to Class 2500
Temperature Range	-50°C to +300°C
Testing & Inspection	PMI, Hydro Testing, Ultrasonic, Visual, Radiography, MPI
Surface Finish	Pickled, Sandblasted, Polished (optional)
Certification	EN 10204 3.1 / 3.2, ISO 9001:2015, NACE MR0175, PED, IBR

Each fitting is supplied with full traceability, supported by Mill Test Certificates (MTCs) and third-party inspection reports from globally recognized agencies such as SGS, TUV, and BV.

By integrating duplex metallurgy with globally benchmarked manufacturing processes, Solitaire Overseas ensures that your Duplex Pipe Fittings are engineered to outperform conventional stainless steel fittings—especially in critical systems that demand structural integrity, long service life, and minimal downtime.

Mechanical Properties And Chemical Composition Of Duplex Steel Fittings

At Solitaire Overseas, we believe that material integrity begins with metallurgical excellence. Our Duplex Steel Fittings, especially in grades like UNS S31803 (Duplex 2205), are engineered to deliver an optimal balance of mechanical strength, corrosion resistance, and toughness—even under extreme operating conditions.

Duplex stainless steels are characterized by a dual-phase microstructure comprising both austenitic and ferritic grains, which gives them nearly twice the strength of conventional austenitic stainless steels (e.g., 304 or 316), while also offering exceptional resistance to chloride-induced stress corrosion cracking, pitting, and crevice corrosion.

Our fittings are manufactured in compliance with international standards such as ASTM A815 and ASME B16.9, and are backed by EN 10204 3.1/3.2 Mill Test Certificates, ensuring full transparency and material traceability.

Chemical Composition of Duplex Stainless Steel (UNS S31803)

Element	Percentage (%)
Chromium (Cr)	21.0 – 23.0
Nickel (Ni)	4.5 – 6.5
Molybdenum (Mo)	2.5 – 3.5
Manganese (Mn)	≤ 2.0
Silicon (Si)	≤ 1.0
Nitrogen (N)	0.08 – 0.20
Carbon (C)	≤ 0.030
Phosphorus (P)	≤ 0.030
Sulfur (S)	≤ 0.020
Iron (Fe)	Balance

This precise balance of alloying elements enhances the material’s ability to withstand aggressive media, especially in applications exposed to seawater, acids, and chlorides.

Mechanical Properties of Duplex Stainless Steel (UNS S31803)

Property	Value	Standard/Test Method
Tensile Strength (min)	620 MPa	ASTM A370
Yield Strength (min)	450 MPa	ASTM A370
Elongation (min)	25%	ASTM A370
Hardness (Brinell, max)	≤ 290 HB	ASTM E10
Impact Toughness	Excellent (Even at Sub-Zero Temps)	EN 10045-1

These properties make Duplex Pipe Fittings ideal for high-pressure systems, structural assemblies, and corrosion-sensitive environments in sectors such as oil & gas, desalination, marine, chemical processing, and power generation.

Industries & Applications of Duplex SS Fittings

When reliability, corrosion resistance, and mechanical strength are critical, Duplex Stainless Steel (DSS) Fittings stand out as the trusted choice across a wide spectrum of high-performance industries. At Solitaire Overseas, we supply precision-engineered Duplex SS Fittings, including UNS S31803 (Duplex 2205), that meet the stringent demands of modern infrastructure—backed by international certifications and years of metallurgical expertise.

Our fittings are designed and manufactured under strict quality control to comply with global standards such as ASTM A815, ASME B16.9, and EN 10253, ensuring performance consistency across critical applications.

Industries That Rely on Duplex Pipe Fittings

Industry	Application Areas
Oil & Gas	Subsea pipelines, manifolds, wellheads, separators, FPSOs, heat exchangers
Petrochemical & Refining	Reactor units, condensers, hydrocrackers, high-pressure loop systems
Marine & Offshore	Ballast water systems, riser pipelines, shipbuilding, underwater structures
Water Treatment & Desalination	RO plants, brine lines, chlorinated water systems, filtration skids
Power Generation	HRSGs, condenser lines, cooling systems, superheated steam loops
Pulp & Paper	Chemical recovery units, digesters, bleach plants, black liquor pipelines
Pharmaceutical & Food Processing	Sanitary pipelines exposed to aggressive cleaning agents or moderate chlorides
Mining & Metallurgy	Acid leach systems, slurry lines, chemical transport pipelines

Why Choose Solitaire Overseas for Duplex Fittings?

Solitaire Overseas is a globally trusted manufacturer and supplier of Duplex Stainless Steel Fittings, known for delivering engineering-grade precision, certified quality, and long-term performance. Specializing in high-performance grades such as UNS S31803 (Duplex 2205), we manufacture fittings in compliance with international standards like ASTM A815, ASME B16.9, and EN 10253. All products are produced in ISO 9001:2015-certified facilities and come with full traceability, Mill Test Certificates (EN 10204 3.1/3.2), and optional third-party inspections from SGS, TUV, or BV—ensuring consistent compliance with PED, NACE MR0175, and IBR requirements.

With a strong global footprint across 60+ countries, Solitaire Overseas supports critical sectors such as oil & gas, petrochemicals, desalination, marine, and energy. Our team of technical experts assists clients in choosing the right fittings based on pressure class, media type, and corrosion exposure, backed by fast lead times and dependable global logistics. We go beyond just supplying fittings—we deliver value, reliability, and technical trust that industries can count on.

Duplex Steel Fittings Price List

At Solitaire Overseas, we offer a transparent and reliable pricing structure for our wide range of Duplex Steel Fittings, including elbows, tees, reducers, stub ends, and more—engineered to meet critical requirements in offshore, petrochemical, and marine applications. Our fittings are manufactured using high-grade Duplex Stainless Steel (UNS S31803 / Duplex 2205) and comply with ASTM A815 and ASME B16.9 standards. Prices are subject to variation based on size, thickness (SCH10 to SCH160), finish, and documentation requirements (MTCs, NACE compliance, third-party inspection, etc.).

All fittings are tested for mechanical strength, dimensional precision, and corrosion resistance to ensure long-lasting performance in harsh industrial environments. To request a project-specific quote or bulk order pricing, contact our technical sales team. Below is an indicative Duplex Pipe Fittings Price List (in USD, FOB India basis):

Product Type	Grade	Size Range	Schedule	Approx. Unit Price (USD)
90° Elbow	UNS S31803	1/2" – 24"	SCH 40–160	$5 – $85
45° Elbow	UNS S31803	1/2" – 24"	SCH 40–160	$4 – $80
Equal Tee	Duplex 2205	1/2" – 24"	SCH 40–160	$6 – $90
Reducer (Concentric)	UNS S31803	3/4" – 24"	SCH 40–160	$5 – $75
Stub End (Short/Long)	Duplex 2205	1/2" – 24"	SCH 10–80	$4 – $70
Pipe Cap	UNS S31803	1/2" – 24"	SCH 40–160	$3 – $60
Cross Tee	Duplex SS	1/2" – 12"	SCH 40–80	$8 – $95

Note: Prices are indicative and may vary based on quantity, finish, testing, and location. Contact us for precise quotations.

By choosing Solitaire Overseas, you benefit from cost-effective Duplex SS Fittings without compromising on quality, documentation, or service. We ship globally to 60+ countries with full traceability and on-time delivery assurance.

Request a Quote Today

Looking for durable and corrosion-resistant Duplex Stainless Steel Fittings? Contact our technical sales team for pricing, availability, and material selection assistance. We ensure prompt delivery, full compliance, and end-to-end documentation support.

Frequently Asked Questions For Duplex Steel Fittings

Is duplex better than 316?

Yes, duplex stainless steel is generally better than 316 in high-chloride and high-pressure environments. It offers nearly twice the strength, superior resistance to stress corrosion cracking, and better performance in aggressive industrial conditions.

What is the difference between 304 and 2205 duplex stainless steel?

Duplex 2205 has a dual-phase structure that makes it much stronger and more corrosion-resistant than 304. While 304 is suitable for general use, 2205 is preferred in harsh applications like offshore, chemical, and marine industries due to its enhanced mechanical properties.

What is the disadvantage of duplex steel?

Duplex steel can be more difficult to weld and machine due to its higher strength and hardness. It’s also more expensive than standard stainless steels, and improper heat treatment can reduce its corrosion resistance or lead to embrittlement in extreme conditions.

What is the strength of duplex steel?

Duplex steel, such as UNS S31803, typically has a minimum tensile strength of 620 MPa and a yield strength of 450 MPa. This makes it nearly twice as strong as austenitic stainless steels like 304 and 316, while offering excellent corrosion resistance.

Is duplex harder than stainless steel?

Yes, duplex stainless steel is generally harder and stronger than standard austenitic grades like 304 or 316. Its dual-phase microstructure enhances hardness, wear resistance, and mechanical performance, especially under high stress or corrosive environments.