Alloy 926 has a PREN of about 46, computed as %Cr + 3.3 x %Mo + 16 x %N. Offshore and desalination projects prefer grades with PRENs above 40 for seawater service at extreme temperatures.
ASTM B677 Alloy 926 Seamless Tube
Alloy 926 Seamless Tube is a high-performance, super-austenitic 6Mo stainless steel product, also globally recognised as UNS N08926, W.Nr. 1.4529, EN X1NiCrMoCuN25-20-7. We at XTD (Zhejiang Xintongda Special Steel) are a trusted manufacturer and supplier of Alloy 926 seamless tubes. Our Incoloy 25-6MO tubes conform to ASTM B677 and B673. Our team cold-rolls, draws, anneals, pickles, and straightens each tube. This ensures your project receives the structural integrity and dimensional correctness that industrial requirements demand.
Alloy 926 Seamless Tube actively resists pitting, crevice corrosion, and stress corrosion cracking. Its chemical composition includes 19–21% Cr, 24–26% Ni, 6–7% Mo, 0.5–1.5% Cu, and 0.15–0.25% N. High-chloride environments like saltwater benefit significantly from 6% molybdenum. Thanks to thermal flexibility, mechanical properties and corrosion resistance remain constant from -196°C to 450°C. Engineers trust this material for consistent performance in extremely challenging chemical processing industries.
To manage large industrial projects, we focus inventory efficiency and supply chain optimisation. We achieve this through our 25,000-ton manufacturing capacity and global infrastructure. We offer flexible manufacturing with lead times of 15 to 60 days for custom manufacture. Engineers seeking manufacturing, with lead times ranging from hours in the most demanding worldwide industries, choose us for our quality and speed.
Product specifications:
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Standard
ASTM B677
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OD Range
6-457 mm
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Thickness
1-65 mm
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Length
≤ 18 m
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How Alloy 926 Seamless Tube is Produced
Quality alloy 926 seamless tubes are produced using precise production processes. The seamless shell is hot extruded or perforated from a super-austenitic 6Mo stainless steel ingot. The precise dimensions are achieved by cold drawing, cold rolling, and pilger rolling.
Solution annealing restores microstructure, followed by pickling for a clean surface finish. Straightening, eddy-current testing, and hydrostatic pressure testing complete the process before cut-to-length and packaging. To know more about our manufacturing process, visit our page.
Key Features of Alloy 926 Seamless Tube
The following are key features of Alloy 926 that ensure the quality of the Alloy 926 Seamless Pipe makes it ideal for major applications.
- Superior chloride pitting resistance: Seawater, generated water, and acid-chloride environments have excellent pitting resistance with a PREN of 46. The 40-PREN threshold for seawater service at extreme temperatures is exceeded by Alloy 926.
- Excellent resistance to chloride SCC: High nickel and molybdenum content delivers near-immunity to chloride stress corrosion cracking in service environments up to 150°C. The duplex-like Ni-Mo-N balance maintains structural integrity under sustained tensile stress.
- Good resistance to sulfuric and phosphoric acids: Combining copper with high molybdenum actively provides acceptable corrosion rates in wet-process phosphoric acid streams. This protects your chemical processing plants from the damage caused by dilute to intermediate sulfuric acid concentrations.
- High strength and toughness: Nitrogen strengthening yields tensile strength above 650 MPa with retained toughness at cryogenic temperatures down to -196°C, making it suitable for LNG and cold-climate applications.
- Weldable with matching filler: Alloy 926 is weldable by GTAW, GMAW, and SMAW using matching 6Mo filler. Overmatching nickel-base filler is sometimes specified to ensure full corrosion property retention across the weld zone.
- Cost-effective vs nickel-base alloys: It provides performance comparable to several nickel-base alloys at reduced material cost in chloride-dominated environments, offering procurement managers a strong value-to-performance ratio.
ASTM B677 Alloy 926 Seamless Tube Equivalent Materials
Alloy 926, a well-known super-austenitic 6Mo stainless steel, is specified across global industries. Common international equivalents support a consistent supply for engineering projects worldwide.
| Grade | UNS | DIN/EN | W.Nr. |
| Alloy 926 | N08926 | X1NiCrMoCuN25-20-7 | 1.4529 |
100% Certified Testing & Documentation
For every shipment of Alloy 926 seamless tubes, we document the chemical composition, mechanical properties, corrosion resistance, and dimensional precision. We at XTD have held multiple international certifications since 1985 and can supply EN 10204 3.1 and 3.2 upon request.
- EN 10204 3.1 and 3.2 Material Test Certificates (MTC)
- 100% PMI (Positive Material Identification)
- Heat Treatment Charts
- Third-Party Inspection Reports (TPI / TUV / BV / SGS)
- Manufacturer Test Certificate: Impact, Flattening, Flare, Bend, Hardness, Intergranular, Pitting Corrosion, Grain Size, ET, UT, HT
- Laboratory Test Certificate from a Government-Approved Lab
Alloy 926 Seamless Tube Industrial Applications
XTD supplies Alloy 926 seamless tubes to demanding industries, including offshore oil and gas, power generation, chemical processing, and desalination.
Offshore Oil and Gas Topsides Piping
We supply Alloy 926 pipes for topside seawater cooling, firewater, and produced-water piping where chloride pitting is the limiting corrosion mechanism. The PREN of 46 keeps maintenance cycles long in hot seawater environments.
Seawater-Cooled Heat Exchangers
Our tubes serve shell-and-tube heat exchangers and condensers with seawater or brackish water on the tube side. High molybdenum content prevents under-deposit pitting in low-flow zones.
Flue Gas Desulfurisation Systems
We provide Alloy 926 for FGD scrubber internals, spray headers, and chloride-rich recirculation piping where chloride levels disqualify standard austenitic grades.
Pulp and Paper Bleaching Plants
Our pipes are used in chlorine-dioxide bleaching stages where chloride levels exceed the limits of standard austenitic stainless steels, requiring a proven high-PREN alloy.
Chemical Processing Piping
We supply Alloy 926 for mixed-acid and organic-chloride service in fine-chemical and pharmaceutical plants where corrosion rates must remain below engineering acceptance limits.
Desalination Plants
Our pipes serve multi-stage flash and reverse-osmosis seawater desalination plants in brine heaters and high-pressure piping where concentrated chloride and elevated temperature combine.
Frequently Asked Questions
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What is the PREN of Alloy 926 and why is it important?
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How does Alloy 926 differ from 904L Stainless Steel?Alloy 926 contains higher molybdenum (6–7% vs 4–5%) and added nitrogen, delivering roughly 30% higher pitting resistance and stronger tensile properties compared with 904L at similar cost.
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Is Alloy 926 suitable for NACE sour service?Yes. Alloy 926 meets NACE MR0175 / ISO 15156 requirements for sour-service applications when supplied in the solution-annealed condition with hardness below the specified limits.
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What standards apply to Alloy 926 Seamless Pipes?Seamless pipes are manufactured to ASTM B677 and ASTM B673. ASME SB-677 applies to code service. Additional tests to ASTM G48 and A262 can be performed on request.