close
Choose Your Site
Global
Social Media
loading
| Availability: | |
|---|---|
| Quantity: | |
654SMO seamless stainless steel pipe (UNS S32654, EN 1.4652) is a premium super austenitic alloy designed for extreme resistance to pitting, crevice corrosion, and stress-corrosion cracking (SCC) in highly chlorinated environments. Composed of 24-26% chromium, 21-23% nickel, 7-8% molybdenum, 0.4-0.6% nitrogen, and balanced iron, it holds the highest alloy content among commercial austenitic steels, achieving a Critical Pitting Temperature (CPT) >80°C. Manufactured via seamless hot-piercing and cold-drawing to ensure tight dimensional control, it complies with standards like ASTM A213, ASME SA213, and EN 10216-5.
The combination of high chromium, molybdenum, and nitrogen creates a robust passive film that resists even the most aggressive chloride solutions, making 654SMO a cost-effective alternative to nickel-based alloys in certain applications.
| Grade | C | Si | Mn | P | S | Cr | Ni | Cu | N | Mo |
| 654 SMO/UNS S32654 | ≤0.02 | ≤0.50 | 2.00-4.00 | ≤0.03 | ≤0.005 | 24.00-25.00 | 21.00-23.00 | 0.30-0.60 | 0.45-0.55 | 7.00-8.00 |
| STS | USA | UNS | CHINA | EURONORM | RUSSIA | SWEDISH | JAPANESE | |
| GRADE | AISI/ASTM | NO | GB | NO | NAME | GOST | SS | JIS |
| 654 SMO | 654 SMO | S32654 | – | 1.4652 | – | – | – | – |
Unmatched Chloride Resistance: Resists pitting in seawater (35,000 ppm Cl⁻) at 60°C and crevice corrosion in stagnant chloride solutions (50,000 ppm Cl⁻ + 1000 ppm Fe³⁺).
High Strength & Ductility: Nitrogen strengthens the austenitic matrix, providing yield strength (≥350 MPa) twice that of 316L without compromising formability.
Temperature Range: Operates from -196°C (cryogenic) to 400°C, with good oxidation resistance up to 850°C in intermittent service.
Fabrication Flexibility: Weldable using GTAW with 654SMO filler metal; cold forming requires preheating for thick sections to prevent strain-induced martensite.
| Grade | Tensile strength (MPa) | 0.2% proof strength (MPa) | Min. elongation at fracture (%) | Brinell hardness (HB) |
| 654SMO | ≥750 | ≥430 | ≥40 | ≤310 |
1) Refining, chemical equipment;
2) Flue gas desulfurization device for thermal power generation, wastewater treatment;
3) Atomic power generation, comprehensive utilization of coal, and ocean wave power generation;
4) Marine structures in the sea environment, seawater desalination, marine aquaculture, seawater heat exchange;
5) Salt production, soy sauce brewing food field;
6) Paper industry, high concentration chloride ion environment of various bleaching devices;
7) Oil and gas industry equipment;
8) Offshore platforms, heat exchangers, underwater equipment, firefighting equipment;
9) Chemical processing industry, utensils and pipeline industry;
10) Desalted plants, high pressure RO plants and submarine pipelines;
11) High-strength, corrosion-resistant mechanical equipment and components;
12) Others.
654SMO(EN 1.4652/UNSS32654) is a special stainless steel containing a high percentage of Nickel and Chromium containing 7% Molybdenum,which is the highest corrision restistance in the world.
It has a fairly high electrical conductivity among wrought superaustenitic stainless steels. In addition, it has the lowest thermal conductivity and very high tensile strength.
654SMo (S32654, 1.4652) super austenitic stainless steel features very good local corrosion resistance, good pitting resistance and good stress corrosion resistance under seawater, aeration, gap and low speed scouring conditions. It can be used as a good substitute to nickel-based alloys and titanium alloys. When it comes to high-temperature resistance or corrosion resistance, it is also superior to 904L and 254SMo.
End of Pipe and Tube
Ply Wooden Boxes
PE Fabric Bundles
Standard seaworthy export packing
Plastic Bags, or as required
Marking
Supplier / Manufacturer Name or Custom Logo - on request
Specification
Material Grade
Nominal Size
Schedule or Wall Thickness
Method of Manufacturing (Seamless or Welded)
Heat Number
Marked Pipe Sample: XTD ASTM A312 654SMO SEAMLESS 42.2x 3.56*6000MM HEAT NO. 2023121205A15
Packing
Ply Wooden Boxes
PE Fabric Bundles
Standard seaworthy export packing
Plastic Bags, or as required
Delivery Condition
Pickled&Annealed, Polished, Bright Annealed.
All tubes shall be supplied as per applicable ASTM B163 /B426
Mill test certificates will be issued
We can provide 3.2 Certification according to the needs of you
Standard
ASTM A312: Standard Specification for Seamless, Welded, and Heavily Cold Worked Austenitic Stainless Steel Pipes
ASTM A213: Standard Specification for Seamless Ferritic and Austenitic Alloy-Steel Boiler, Superheater, and Heat-Exchanger Tubes
Q: Why is 654SMO called a "super austenitic" steel?
A:Its alloy content (Cr, Ni, Mo, N) exceeds standard austenitic grades, achieving a PREN (Pitting Resistance Equivalent Number) >50, classifying it as a super alloy for chloride resistance.
Q: How does it compare to duplex stainless steels like 2507?
A:654SMO has better ductility and impact toughness at low temperatures but lower strength than duplex; choose based on chloride concentration and design stress requirements.
Q: Can 654SMO be used in hydrofluoric acid?
A:No, high molybdenum makes it susceptible to HF attack; nickel-copper alloys like Monel 400 are preferred for HF environments.
Q: What is the typical price range compared to 316L?
A:654SMO costs 3-4 times more than 316L due to its high alloy content, justified by extended service life in critical chloride environments.
