Duplex and Super Duplex Stainless Steel Fittings Supplier, Stockist and Exporter

Aurico Alloys LLP supplies duplex steel fittings from ready stock in Mumbai to customers across India and in more than 40 export markets. Fittings carry the same corrosion duty as the pipe they join but see higher stress concentration at every change of direction, so grade traceability and wall thickness at the extrados matter more here than anywhere else in a piping system.

Duplex Steel covers dual-phase austenitic-ferritic stainless steels giving roughly twice the yield strength of 316L with far better chloride resistance. Fittings are supplied with heat-number traceability and can be bevelled, tacked or pre-fabricated into spools on request.

Sizes and Specifications

Duplex Steel Fittings - standard supply range
Size rangeButt-weld fittings 1/2" to 48" NB in Sch 5S to Sch XXS; forged socket-weld and threaded fittings 1/8" to 4" NB in 3000#, 6000# and 9000# classes.
Types and finishesElbows (45° and 90°, long and short radius), tees (equal and reducing), reducers (concentric and eccentric), caps, stub ends, couplings, unions, plugs and bushings.
SpecificationsASME B16.9 and B16.28 for butt-weld, ASME B16.11 for forged fittings, with material to ASTM B366 / A815 / B363 as applicable.
CertificationEN 10204 3.1 mill test certificate; 3.2 and third-party inspection on request
OriginIndian and imported mills, fully traceable by heat number

Specifications by Grade – Fittings

A specification is written for a product form. The standards below are the ones that cover fittings; the plate, bar and tube specifications for these grades are different documents and are listed on their own pages.

GradeUNSFittings specification
2205S32205ASTM A815
32750S32750ASTM A815
32760S32760ASTM A815

Grades and International Equivalents

Duplex Steel grades stocked, with UNS and Werkstoff equivalents
GradeUNSWerkstoff (W.Nr.)
Duplex 2205S31803 / S322051.4462
Lean Duplex 2101S321011.4162
Duplex 2304S323041.4362
Super Duplex 2507 / F53S327501.4410
Super Duplex F55 (Zeron 100)S327601.4501

Chemical Composition

Duplex 2205 runs 22% Cr, 5.5% Ni and 3.1% Mo with 0.14-0.20% nitrogen. Super duplex grades raise chromium to 25% and molybdenum to 4% for a PREN above 40.

Mechanical and Physical Properties

Minimum yield strength is 450 MPa for 2205 and 550 MPa for 2507, roughly double that of 316L. The balanced microstructure resists chloride stress-corrosion cracking that defeats standard austenitic grades.

Industry Applications

How fittings is used

Fittings are factory-made wrought components to ASTM B366, dimensioned to ASME B16.9 for butt-weld and ASME B16.11 for socket-weld. They are the 45, 90 and 180 degree elbows, tees, reducers, caps and lap-joint stub ends that change direction, branch or change bore in a process line, and they are specified to match the pipe they join in both alloy and schedule so the weld and the corrosion behaviour stay continuous.

Where duplex steel fittings is specified
IndustryTypical use
Oil and gasSubsea manifolds, flowlines, risers and process piping.
DesalinationHigh-pressure piping, evaporator bodies and brine handling.
Chemical processingPressure vessels, tanks and acid-service piping.
Pulp and paperDigesters, bleaching equipment and liquor handling.
MarineCargo tanks, offshore structure and seawater systems.

Testing and Certification

Every consignment ships with an EN 10204 3.1 mill test certificate stating heat number, chemical analysis and mechanical properties. Depending on grade and specification we can supply positive material identification (PMI), ultrasonic and dye-penetrant testing, intergranular corrosion testing to ASTM A262 or G28, hydrostatic testing, and third-party inspection release notes from Lloyd's Register, Bureau Veritas, SGS or TUV.

Aurico Alloys LLP operates an ISO 9001:2015 quality management system. Material for sour service can be supplied certified to NACE MR0175 / ISO 15156 where the grade permits.

Request a Quotation

Send your grade, size, quantity and specification and we will respond with price and lead time, usually the same working day. Call +91 7977 88 6611 or email info@auricoalloys.com.

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