254 SMO Plates Manufacturer & Supplier

254 SMO plates (UNS S31254) are super-austenitic stainless steel flat products made according to ASTM A240 and ASME SA-240. The most important feature of this alloy is its molybdenum content of 6.0 to 6.5%, which gives it a Pitting Resistance Equivalent Number (PREN) above 42. Its main alloying elements are chromium at 19.5 to 20.5%, nickel at 17.5 to 18.5% and nitrogen at 0.18 to 0.22%. These plates provide a minimum tensile strength of 650 MPa (94 ksi), a yield strength of 300 MPa (44 ksi) and an elongation of 35%. The nitrogen addition strengthens the austenitic structure and increases resistance to crevice corrosion in chloride-rich environments such as seawater handling and desalination systems.

Sachiya Steel International, headquartered in Mumbai, India, is a reliable manufacturer, supplier, stockist, and exporter of 254 SMO plates. With more than 20 years of expertise in super-austenitic stainless steel products, we hold ISO 9001, ISO 14001, and ISO 45001 certifications. We maintain a ready stock of plates, and each shipment is supplied with mill test certificates in accordance with EN 10204 3.1 and 3.2, along with seaworthy export-quality packaging.

Plate thicknesses start at 4.5 mm and go up to 100 mm. They can be up to 2400 mm wide and 12000 mm long. Custom dimensions are also available. You'll find these plates in a variety of applications, including offshore seawater systems, chemical processing plants, pulp and paper bleach lines, and flue gas desulphurisation scrubbers. Available surface finishes include 2B, BA, No.4 satin and hot rolled.

This page covers:

Specifications
Pricing
Chemical Composition
Mechanical Properties
Equivalent Designations
Industrial Applications
Grade Comparison
Shipping & Packaging
Frequently Asked Questions

254 SMO Plate Specifications

SMO 254 plates are high-alloy stainless steel products used for pressure vessels and general industrial applications. They are supplied as plates, sheets, and strips made from chromium- and chromium‑nickel stainless steel, offering high strength and excellent corrosion resistance.

Property	Details
Standard	ASTM A240 / ASME SA-240
Thickness	4.5 mm to 100 mm
Width	900 mm to 2400 mm
Length	3000 mm to 12000 mm
Surface Finish	2B, 2D, BA, No.4 Satin, 8K Mirror, Hot Rolled
Delivery Condition	Annealed & Pickled, Solution Treated

Size, Weight and Finishes are mentioned below:

Available in a range of sizes, finishes, and forms to suit different project requirements. Key specifications are listed below.

Property	Details
Category	Plates
Product Type	254 SMO Plate
Thickness	4.5 mm – 100 mm
Width	900 mm – 2400 mm
Length	3000 mm – 12000 mm

Forms & Finishes

254 SMO plates are supplied in hot rolled, cold rolled, clad, perforated, and chequered or tread plate forms. Polished finishes include 8K mirror, No.4 satin, BA, 2B, and 2D. Shim sheet, coil, strip, and foil are also available.

254 SMO Plate Price Per Kg

254 SMO plate prices in India are usually between Rs 700 and Rs 900 per kg. The exact rate depends on the plate’s thickness, width, surface finish and the total quantity you order. For international buyers, prices are typically USD 8 to 11 per kg. These rates vary based on the producing mill, shipping terms (FOB, CIF, CFR), and whether you need EN 10204 3.1 or 3.2 certification. Since nickel and molybdenum prices change often, 254 SMO plate prices also vary.

Chemical Composition of 254 SMO Plates

The table below lists the chemical composition of 254 SMO plates (UNS S31254) per ASTM A240 / ASME SA-240.

High molybdenum and nitrogen content set this grade apart from standard 300-series austenitic steels. The low carbon limit of 0.020% max supports weldability and reduces sensitisation risk.

Carbon C

Max 0.020%

Manganese Mn

Max 1.00%

Phosphorus P

Max 0.030%

Sulphur S

Max 0.010%

Silicon Si

Max 0.80%

Chromium Cr

19.5 – 20.5%

Nickel Ni

17.5 – 18.5%

Molybdenum Mo

6.0 – 6.5%

Copper Cu

0.50 – 1.00%

Nitrogen N

0.18 – 0.22%

Mechanical Properties of 254 SMO Plates

Below are the mechanical properties of 254 SMO. These plates deliver nearly twice the yield strength of standard austenitic grades like 304 or 316L.

650 (94)

MPa (ksi)

Tensile Strength

300 (44)

MPa (ksi)

Yield Strength

35%

(min)

Elongation

8.0

g/cm3

Density

Property	Details
Tensile Strength (min)	650 MPa (94 ksi)
Yield Strength, 0.2% Offset (min)	300 MPa (44 ksi)
Elongation (min)	35% in 50 mm
Density	8.0 g/cm3

Contact our sales team for stock availability and competitive pricing. Request a Quote

Equivalent Designations

The table below shows international equivalent grades for 254 SMO plates. It assists engineers and procurement professionals in aligning material specifications with international standards, ensuring the selection of the most suitable material.

Property	Details
UNS	S31254
Germany (DIN)	1.4547
Europe (EN)	X1CrNiMoCuN20-18-7
Sweden (SS)	2378
Japan (JIS)	SUS 312L
China (GB/T)	00Cr20Ni18Mo6CuN

Applications of 254 SMO Plates

6Mo plates perform in high-chloride and aggressive corrosion environments where standard austenitic steels fail. 4 primary sectors drive demand for this grade.

Offshore & Seawater Systems

254 SMO plates are used in seawater cooling circuits, fire-fighting pipework, and offshore platform structures. The PREN above 40 prevents pitting and crevice corrosion in warm, chloride-bearing water.

Chemical & Petrochemical Processing

The alloy handles concentrated sulphuric acid, phosphoric acid, and chloride process streams. Heat exchangers and reactor vessels in chemical plants rely on their corrosion performance.

Pulp & Paper Industry

Bleach plant equipment and chlorine dioxide washers use Alloy 254 plates. Chloride-rich bleaching chemicals attack lower-grade steels that can’t match 254 SMO’s resistance.

Energy & Desalination

Flue gas desulphurisation scrubbers and desalination evaporators operate in acidic condensate conditions. 254 SMO plates resist the combination of high temperature and aggressive chemistry in these systems.

254 SMO Plates vs SS 316 Plates

This comparison shows the main differences between 254 SMO and Stainless Steel 316 plates, so buyers can judge corrosion resistance, strength, and composition and choose the right material for tough industrial conditions.

Property	254 SMO (UNS S31254)	SS 316 (UNS S31600)
Material Type	Super Austenitic Stainless Steel	Austenitic Stainless Steel
Chemical Composition (%)	Cr: 19.5–20.5, Ni: 17.5–18.5, Mo: 6.0–6.5, N: 0.18–0.22	Cr: 16.0–18.0, Ni: 10.0–14.0, Mo: 2.0–3.0, N: 0.10 max
PREN (Pitting Resistance Equivalent Number)	> 42	~ 25
Tensile Strength (min)	650 MPa	515 MPa
Yield Strength (min)	~ 300 MPa	~ 205 MPa

254 SMO Plates vs 904L Plates

This comparison covers the key differences between 254 SMO and 904L Stainless Steel plates, helping buyers understand corrosion resistance, alloy composition, and performance in chloride-rich and acidic environments.

Property	254 SMO (UNS S31254)	904L (UNS N08904)
Material Type	Super Austenitic Stainless Steel	High Alloy Austenitic Stainless Steel
Chemical Composition (%)	Cr: 19.5–20.5, Ni: 17.5–18.5, Mo: 6.0–6.5, N: 0.18–0.22, Cu: ≤0.5	Cr: 19.0–23.0, Ni: 23.0–28.0, Mo: 4.0–5.0, N: ≤0.10, Cu: 1.0–2.0
PREN (Pitting Resistance Equivalent Number)	> 42	~ 34
Tensile Strength (min)	650 MPa	490 MPa
Yield Strength (min)	~ 300 MPa	~ 220 MPa
Pitting & Crevice Corrosion Resistance	Excellent (Superior in chlorides)	Very Good
Chloride Resistance	Outstanding (Seawater grade)	Good
Resistance to Reducing Acids	Moderate	Excellent (due to Copper content)
Stress Corrosion Cracking Resistance	High	Moderate
Cost	High	High (but generally lower than 254 SMO)
Typical Applications	Offshore seawater systems, desalination	Acid handling, chemical processing, fertiliser plants

Shipping & Packaging

Heavy-duty wooden boxes Packing

Export Packaging Standard

We strictly follow seaworthy export handling standards to protect 254 smo plate from transit damage, moisture ingress, and surface contamination during long-distance dispatch.

Heavy-duty wooden boxes with moisture barrier lining
HDPE stretch film wrapping on all bundles
Edge and corner protection with plastic padding
Silica gel desiccants to minimize moisture exposure
ISPM-15 fumigated wooden packaging for export

Plate Bundle Yard Staging

Plate Bundle Edge Protection

Wrapped Export-Ready Bundles

We Export Worldwide

Sachiya Steel International supplies stainless steel products to major industrial markets across North America, Europe, the Middle East, Asia and Africa with export-ready documentation and logistics support.

USA
Canada

Frequently Asked Questions:

What is the difference between 254 SMO Plates and SS 316 Plates? +

254 SMO plates, which contain 6% molybdenum, have a higher PREN (more than 40) than SS 316 plates (~25), which contain 2-3%. Therefore, 254 SMO is better suited for use in chemical environments with high chloride levels, where SS 316 plates are not resistant to pitting.

What is the difference between 904L and 254 SMO Plates? +

254 SMO has a higher amount of molybdenum, ranging from 6.0% to 6.5%, compared to 4.0% to 5.0%. It also has a higher nitrogen content, between 0.18% and 0.22%. Its PREN exceeds 40, while 904L reaches approximately 34. For severe crevice and pitting corrosion, 254 SMO is the stronger option.

What ASTM specification covers 254 SMO Plates? +

ASTM A240 / ASME SA-240 is the applicable standard for 254 SMO plates, sheets and strips intended for pressure vessels and general applications.

What sizes are 254 SMO Plates available in? +

Thicknesses range from 4.5 mm to 100 mm, widths from 900 mm to 2400 mm, and lengths from 3000 mm to 12000 mm. Custom dimensions are available on request.

What is the price of 254 SMO Plates per kg? +

In India, prices fluctuate between Rs 700 and Rs 900 per kilogram; internationally, the cost ranges from $8 to $11 per kilogram elsewhere. The ultimate cost is influenced by factors such as thickness, the desired finish, the amount ordered, and the prevailing rates of raw materials.

Can 254 SMO Plates be welded? +

Yes. GTAW (TIG) welding with ERNiCrMo-3 filler metal (per AWS A5.14) produces sound joints. Preheating isn’t required. Welding without matching filler metal results in welds with inferior corrosion resistance and mechanical strength.

What is the equivalent of 254 SMO Plates in European standards? +

X1CrNiMoCuN20-18-7 is the European equivalent for 254 SMO Plates.

What is the weight of a 254 SMO Plate per square metre? +

The density of 254 SMO is 8.0 g/cm3. Multiply the plate thickness in millimetres by 8.0 to get the weight in kg/m2. A 10 mm thick plate weighs approximately 80 kg per square metre.