High-Cr-Ni-Mo-N super-austenitic stainless steel with enhanced resistance to pitting and crevice corrosion in chloride-rich environments.
Material gradeDuplex & Super Duplex Grades
/ 01 — TECHNICAL OVERVIEW
SMO® 254 (UNS S31254)
Nesco Pipe & Tubes is a manufacturer, supplier, stockist and exporter of SMO® 254 (UNS S31254), offering pipes, tubes, flanges, butt weld fittings, sheets, plates, coils and round bars in specified dimensions, finishes, conditions and testing requirements for industrial and project applications. Availability and applicable standards are confirmed against the customer’s purchase specification.
SMO® 254 is a super-austenitic stainless steel with high chromium, molybdenum and nitrogen content, developed for enhanced resistance to pitting, crevice corrosion and chloride-induced corrosion. Its high-alloy composition provides a combination of corrosion resistance and mechanical performance for demanding process and marine environments.
High-alloy austenitic stainless steel for chemical processing, petrochemical, marine, seawater, desalination, pulp and paper, pharmaceutical and other chloride-rich applications where its corrosion-resistance profile is suitable.
The correct material depends on more than corrosion resistance alone. Temperature, pressure, chloride exposure, chemistry, erosion, fabrication route, weldability, mechanical strength, product form, code requirements and lifecycle cost should be reviewed together. Final grade selection remains with the customer’s qualified engineer, designer or material specialist.
How it is made
01
Controlled melting establishes the required chromium, nickel, molybdenum and nitrogen balance for the specified SMO® 254 grade.
02
Hot working is performed within a controlled temperature range to develop the required product form while maintaining the desired austenitic structure.
03
Solution annealing followed by rapid cooling restores the required metallurgical condition and supports the specified corrosion resistance and mechanical properties.
04
Forming, machining and surface treatment are controlled to minimise surface contamination, heat-affected conditions and factors that may affect corrosion performance.
05
PMI, mechanical, hardness, corrosion and other specified tests are performed according to the applicable product specification and inspection requirements.
Request reviewed quotation Material documents on request
/ 02 — PRODUCT DETAIL
Built around the specification.
Key characteristics and commonly referenced standards for SMO® 254 (UNS S31254).
Key features01 02 03 04
Available across multiple product forms, subject to the applicable product specification, dimensions and availability.
Heat-wise traceability and MTC support.
PMI, NDT and third-party inspection options against specified inspection requirements.
Common specification references
STD
ASTM A240/A240M — Stainless steel plate, sheet and strip
STD
ASTM A312/A312M — Seamless, welded and heavily cold-worked austenitic stainless steel pipe
STD
ASTM A269/A269M — Seamless and welded austenitic stainless steel tubing for general service
STD
ASTM A182/A182M — Stainless steel forgings, flanges and forged components
STD
ASTM A403/A403M — Wrought austenitic stainless steel fittings
STD
ASTM A276/A276M / ASTM A479/A479M — Stainless steel bars and shapes, where applicable
STD
NORSOK / Project Specification — Additional requirements for corrosion resistance, heat treatment, testing, NDT and inspection where specified
/ 03 — MATERIAL RANGE
Grades matched to the service.
Commonly requested families are shown below. Availability is confirmed against the complete specification.
Material familyCommon gradesTypical selection context
Specified gradeSMO® 254 (UNS S31254)
Supply is reviewed by product form, governing standard, condition and service
Alloy familySuper-Austenitic Stainless Steel
Related grades are reviewed against the required specification and service conditions
/ 04 — SUPPLY & CUSTOMISATION
Available forms and enquiry basis.
Pipes, tubes, flanges, butt weld fittings, sheets and plates, coils and round bars.
ParameterTypical Options
01Material family
Common grades
02Specified grade
SMO® 254 (UNS S31254)
03Alloy family
Super-Austenitic Stainless Steel
04
Parameter
05
Available forms
06
Product standard
07
Supply condition
08
Dimensions
09
Testing
10
Documentation
11
Enquiry basis
/ 05 — DIMENSIONS & SIZE RANGE
Dimensions aligned to the manufacturing route.
Dimensions must be specified for the selected product form; a grade designation alone does not define size, tolerance, finish or supply condition.
Product formOrdering dimensionsCondition / finishStandard basis
PipeNPS/OD, wall thickness or schedule, length and endsSeamless/welded, solution annealed, heat treated and finished as specifiedApplicable pipe material and dimensional standards
TubeOD, wall thickness, length or coil/U-bend geometrySeamless/welded, solution annealed and surface finish as specifiedApplicable ASTM/EN product standard
Flat productThickness, width, length or coil geometryHot/cold rolled, solution annealed, pickled or polished as specifiedApplicable flat-product material standard
Bar / forgingDiameter/profile, tolerance and cut lengthHot finished, forged, cold finished or machined as specifiedApplicable bar/forging material standard
/ 06 — MANUFACTURING STANDARDS
Standards aligned for every order.
The material standard, dimensional standard and project requirements should be stated separately.
SMO® 254 (UNS S31254) product-standard references
StandardWhat it covers
ASTM A240/A240MAustenitic stainless steel plate, sheet and strip — Flat products
ASTM A312/A312MSeamless, welded and heavily cold-worked austenitic stainless steel pipe — Tubular products
ASTM A269/A269MSeamless and welded austenitic stainless steel tubing for general service — Tubular products
ASTM A182/A182MStainless steel forgings, flanges and forged components — Piping components
ASTM A403/A403MWrought austenitic stainless steel fittings — Butt-weld and other wrought fittings
ASTM A276/A276M / ASTM A479/A479MStainless steel bars and shapes, where applicable — Long products
NORSOK / Project SpecificationAdditional requirements for corrosion resistance, heat treatment, testing, NDT and inspection where specified — Project-specific
/ 07 — REFERENCE MATERIAL DATA
SMO® 254 (UNS S31254) material reference
A concise engineering reference for procurement. Exact chemical limits and mechanical acceptance values depend on product form, size, condition and the applicable specification edition; the certified material test certificate governs the supplied material.
Chemistry and alloy identityPrincipal alloying profile; certification limits follow the ordered standard.
Material referenceTechnical profile
Grade / designationSMO® 254 (UNS S31254)
Alloying systemHigh-Cr-Ni-Mo-N super-austenitic stainless steel with controlled copper addition
Certification basisHeat analysis and product requirements are certified against the exact material specification stated on the purchase order
Mechanical-property basisProduct-form and condition dependent; verify certified values.
Property basisSupply requirement
Mechanical profileHigh strength relative to conventional austenitic stainless steels is typical; heat treatment, product form and condition remain important
Acceptance valuesTensile strength, yield strength, elongation and hardness requirements are verified against the applicable product-form standard and specified condition
CertificationActual heat/lot test results are reported on the agreed Material Test Certificate (MTC)
/ 08 — INSPECTION & TESTING
Evidence before dispatch.
01Grade / UNS and applicable product-standard verification
02Heat-number traceability and MTC review
03PMI against the specified grade and alloy chemistry
04Dimensions, tolerances and surface-condition inspection
05Mechanical and hardness testing as required by the applicable product specification
06Corrosion or intergranular corrosion testing where specified
07NDT and third-party inspection / witnessing against the approved inspection plan
Testing requirements are applied according to the applicable material/product standard, purchase specification and approved inspection plan.
/ 09 — PACKAGING & MARKING
Protected and traceable.
01Product-form-specific protection for surfaces, machined faces and ends
02Heat-wise segregation and durable grade / heat identification
03Non-contaminating separators and protective materials suitable for stainless steel
04Moisture-resistant wrapping, crates or export packaging where required
05Package markings aligned with grade, heat number, dimensions, quantity and purchase order
Packaging and marking can be adapted to customer, project and export requirements.
/ 10 — APPLICATIONS & INDUSTRIES
Engineered for demanding service environments.
From process plants to marine systems, NESCO coordinates material, dimensions and documentation around the operating conditions of each application.
01
Chemical processing02
Oil and gas03
Power generation04
Marine systems05
Heat exchangers06
Industrial fabricationIndustries servedOne supply partner across critical sectors.
Chemical processingOil & gasPower generationMarineHeat exchangersProcess equipmentGeneral engineering
/ 11 — WHY NESCO PIPE & TUBES
Built for buyers who cannot leave details to chance.
From specification review to export documentation, NESCO coordinates the technical and commercial details as one complete supply requirement.
01
Specification control
NESCO reviews the grade, product standard, dimensions, condition and acceptance criteria as one coordinated requirement.
02
Multi-material sourcing
Stainless steel, duplex, nickel alloy, copper-nickel and titanium requirements can be combined within one project enquiry.
03
Traceable documentation
Heat numbers, MTCs and agreed inspection records are aligned with the purchase order before dispatch.
04
Inspection coordination
PMI, dimensional checks, NDT and third-party witnessing can be arranged against an approved inspection plan.
05
Value-added processing
Cutting, machining, end preparation, polishing or protective finishing can be reviewed with the base material supply.
06
Export-ready packing
Identification, surface protection and packing are planned around product geometry and the final transport route.
07
Responsive RFQ review
Technical and commercial inputs are consolidated early so queries are resolved before quotation and production.
08
One accountable supply desk
NESCO provides a single contact for material, processing, documentation, packing and delivery coordination.
/ 12 — FREQUENTLY ASKED QUESTIONS
Clear answers before you specify.
Quick guidance on product selection, standards, dimensions, inspection and documentation. For project-specific requirements, NESCO will review the complete enquiry with your team.
01What product forms are available in SMO® 254 (UNS S31254)?
Availability can include pipes, tubes, flanges, fittings, sheets, plates, coils and bars, but each form must be confirmed against its own material standard and production range.
02What standard should be specified for SMO® 254 (UNS S31254)?
State both the exact grade/UNS and the product-form material standard. A plate specification cannot be assumed to cover pipe, tube, bar, flange or fitting supply.
03Can NESCO provide chemical and mechanical certificates?
Yes. An agreed material test certificate can report heat analysis and mechanical results required by the ordered specification.
04Can another grade be substituted?
Only with written approval from the responsible engineer after reviewing corrosion, strength, temperature, fabrication and code requirements.
05What information produces the fastest quotation?
Provide grade/UNS, product form, standard, size, condition, quantity, tests, certification and delivery destination.
/ 13 — REQUEST FOR QUOTATION Nesco direct sales desk
Ready to source?Start with the details you already have.
Our team will review the grade, dimensions, testing and delivery requirements together.