ASTM A182 Grade F51 / UNS S31803 Forging Parts — Product Overview
ASTM A182 Grade F51 (also designated UNS S31803, DIN 1.4462, EN X2CrNiMoN22-5-3, or commonly called 2205 duplex stainless steel) is a standard grade of duplex stainless steel forging material defined by ASTM International. It has a consistent microstructure of about 50% austenite and 50% ferrite, with a nominal composition of 22% chromium, 5% nickel, and 3% molybdenum, along with a Pitting Resistance Equivalent Number (PREN) of ≥ 34.
Jiangsu Liangyi Co., Limited is an ISO 9001:2015 and API 6A certified manufacturer of A182-F51 open die forgings and seamless rolled rings, established in Jiangyin, Jiangsu Province, China in 1997. The company covers 80,000 m² and has an annual production capacity of 120,000 metric tons.We have supplied clients in more than 50 countries across six continents.
A182-F51 is a duplex stainless steel with a balanced 50:50 austenite-ferrite microstructure. This unique dual-phase structure provides approximately twice the yield strength of standard 304 or 316L austenitic stainless steels (minimum 448 MPa vs. approximately 170 MPa for 316L) combined with superior resistance to chloride-induced stress corrosion cracking (SCC), pitting corrosion, and crevice corrosion. Forgings are supplied in the solution-annealed condition (1,050–1,100 °C followed by water quenching).
Our Key Advantage: Jiangsu Liangyi provides a full range of in-house manufacturing from steel melting (EAF + LF + VOD) ,open die forging or seamless ring rolling, heat treatment, precision CNC machining to full NDT ,making sure all A182-F51 forged parts will be provided with high quality and competitive prices on time.
UNS S31803 / ASTM A182 Grade F51 — Key Facts at a Glance
621 MPa
Min. Tensile Strength
448 MPa
Min. Yield Strength
≥ 34
PREN (Pitting Resistance)
22-5-3
Cr-Ni-Mo Nominal (wt%)
293 HBW
Max. Hardness (Brinell)
30 t
Max. Single Piece Weight
Values are specified for ASTM A182 / UNS S31803 in the solution‑annealed condition. All properties are verified by our in‑house laboratory and certified based on EN 10204 3.1.
UNS S31803 (A182-F51) Forging Manufacturing Capabilities
We have advanced production facilities so that we can make A182-F51 (UNS S31803) forgings in a wide range of sizes and configurations — from small parts to large heavy-duty parts weighing up to 30 metric tons. All equipment is maintained and operated by technicians with more than 10 years of specialist forging experience.
Advanced Production Equipment
- Forging Presses: 2,000T, 4,000T, and 6,300T hydraulic forging presses
- Forging Hammers: 0.75T, 1T, 3T, 5T, and 9T electro-hydraulic forging hammers
- Seamless Ring Rolling: 1M and 5M CNC-controlled seamless ring rolling machines (maximum diameter 6 meters)
- Heat Treatment: Ten computer-controlled furnaces with ±5 °C temperature precision
- Steel Making: 30T Electric Arc Furnace (EAF) + 30T Ladle Refining Furnace (LF) + 30T Vacuum Oxygen Decarburization (VOD) + 2T medium-frequency induction furnace
- Machining: Large CNC lathes, milling machines, drilling machines, grinding machines, and boring machines
Complete In-House Manufacturing Process
- inspect raw material and chemical composition by optical emission spectrometry (OES)
- Melt and refine steel (EAF + LF + VOD for premium cleanliness and nitrogen control)
- Cast ingot and surface conditioning
- Forging the open die (up to 6,300T) or roll the seamless ring (up to 6 m diameter)
- Perform Solution annealing at 1,050–1,100 °C (1,920–2,010 °F) followed by rapid water quenching
- Provide rough and precision CNC machining according to customer drawings and tolerances
- Provide full non-destructive testing (UT, PT, MT, RT) and destructive testing
- Inspect final goods, mark heat number , package anti-rust , and export
View our complete production equipment list and product capabilities for more details.
ASTM A182 Grade F51 Forged Steel — Available Shapes & Dimensions
We make a full range of A182-F51 (UNS S31803) forging steel products in all kinds of shapes and sizes to meet different industrial needs. All products can be custom manufactured based on client's drawings, specifications, and tolerances.
- Forged Bars: Round bars (max. diameter 2,000 mm), square bars, flat bars, rectangular bars, and hollow bars
- Seamless Rolled Rings: Custom forged rings up to 6 meters in diameter and 30 tons in weight — gear rings, slewing bearing rings, contoured rolled rings, and valve body rings
- Forged Shafts: Step shafts, gear shafts, turbine shafts, crankshafts, and custom shafts up to 15 meters in length
- Hollow Components: Hubs, housing shells, sleeves, bushes, and heavy-wall cylinders (max. OD 3,000 mm)
- Flat Products: Discs, blocks, plates, tube sheets, blind flanges, weld neck flanges, and slip-on flanges
- Piping Products: Pipes, tubes, piping shells, casings, and housings
- Valve & Oil-Gas Components: Valve bodies, bonnets, stems, balls, seats, closures, wellhead spool bodies, casing heads, tubing heads, and BOP parts
Production Specifications: Weight of single-piece ranges from 30 kg to 30,000 kg . Our annual capacity is 120,000 metric tons . Normal lead time is 2–6 weeks (expedited production is available)
UNS S31803 / ASTM A182 Grade F51 — Global Industrial Applications
ASTM A182 Grade F51 (UNS S31803) forgings are used in extreme industrial conditions where high strength, excellent corrosion resistance, and long lifetime are essential. Following are the primary applications and actual project examples.
Oil and Gas Industry (Middle East, North America, South America)
A182-F51 is the best choice material for upstream, midstream, and downstream oil and gas operations ,and it has excellent resistance to sour service environments containing H₂S, chloride-induced SCC, and pitting corrosion. It meets API 6A, NACE MR0175, and NACE MR0103 standards.
- Wellhead Equipment: Christmas trees, wellhead spool bodies, casing heads, tubing heads, casing hangers, tubing hangers, and spacer spools are for onshore and offshore wells in Saudi Arabia, UAE, Qatar, USA, and Brazil
- Subsea Equipment: Subsea manifolds, jumpers, connectors, flowline components, and tree systems for deepwater projects in the Gulf of Mexico and Brazil
- Blowout Preventers (BOP): RAM, annular, and dual BOP bodies and blocks for offshore drilling platforms
- Valve Components: High-pressure ball valves, gate valves, check valves, butterfly valves, and choke valves for pipeline systems
- Flow Control Equipment: Double studded adapter flanges, integral mud flanges, flanged outlets, and studded crosses
Power Generation Industry (Asia, Europe, North America)
F51 duplex stainless steel forgings play an important role in both conventional and renewable power generation.They have excellent performance in high-temperature and corrosive environments.
- Nuclear Power: Reactor coolant pump casings, heat exchanger tube sheets, baffle plates, channel flanges, and containment parts in China, France, and the USA
- Fossil Power: Boiler tubes, superheater headers, turbine parts, and generator parts for thermal power plants
- Renewable Energy: Wave and tidal energy parts, geothermal power plant equipment, and wind turbine hub parts
Chemical and Petrochemical Industry (Europe, Asia, North America)
UNS S31803 has great corrosion resistance, so that it is the best choice material for handling aggressive chemicals and process fluids in the chemical industry.
- Process Equipment: Pressure vessels, reactors, heat exchangers, separators, and distillation columns
- Pump and Compressor Components: Pump casings, covers, barrels, impellers, shafts, housings, and wear rings
- Piping Systems: Process piping, fittings, and flanges for corrosive chemical transport
- Measurement Equipment: Venturi cone meter bodies, oil measurement valve spools, and ultrasonic flow meter bodies
Mining and Mineral Processing (Australia, Africa, South America)
A182-F51 forgings are used in mining equipment where high strength and resistance to abrasive and corrosive slurries are needed.
- Mining Machinery: Crusher parts, grinding mill parts, slurry pump parts, and hydrocyclone parts
- Material Handling: Conveyor rollers, pulleys, bucket components, and chute liners
Marine and Offshore Industry (Global)
A182-F51 forgings have excellent resistance to seawater corrosion (critical temperature up to approximately 25 °C) and are the best choice material for marine and offshore applications.
- Shipbuilding: Propeller shafts, rudder parts, hull fittings, and stern tube parts
- Offshore Structures: Platform parts, risers, mooring systems, and jacket parts
- Desalination Plants: High-pressure pumps, valves, piping, and pressure vessels for reverse osmosis systems in the Middle East and Mediterranean regions
View our complete project reference list for more examples of our global project experience.
Chemical Composition of ASTM A182 Grade F51 / UNS S31803 Duplex Stainless Steel
A182-F51 duplex stainless have controlled chemical composition, which ensures they have excellent mechanical strength and corrosion resistance. All material is tested and certified to meet ASTM A182, UNS S31803, EN 10088-3, and DIN 1.4462 standards. Chemical analysis is performed on every heat by optical emission spectrometry (OES).
| Element | Min. Weight % | Max. Weight % | Role in Alloy |
|---|
| Carbon (C) | — | 0.030 | Controlled low to prevent carbide precipitation |
| Manganese (Mn) | — | 2.00 | Austenite stabiliser; aids hot workability |
| Phosphorus (P) | — | 0.030 | Impurity — kept low for toughness |
| Sulfur (S) | — | 0.020 | Impurity — kept low for corrosion resistance |
| Silicon (Si) | — | 1.00 | Deoxidiser; aids oxidation resistance |
| Chromium (Cr) | 21.00 | 23.00 | Primary corrosion resistance former |
| Nickel (Ni) | 4.50 | 6.50 | Austenite stabiliser; toughness |
| Molybdenum (Mo) | 2.50 | 3.50 | Pitting/crevice corrosion resistance (PREN booster) |
| Nitrogen (N) | 0.08 | 0.20 | Austenite stabiliser; increases strength and PREN |
| Iron (Fe) | Balance | Balance | — |
PREN formula: PREN = %Cr + 3.3×%Mo + 16×%N. For UNS S31803 at normal composition this yields PREN is ≥ 34, compared to ~24 for 316L.
Mechanical Properties of UNS S31803 (ASTM A182 Grade F51) Forgings
Our A182-F51 (UNS S31803) forgings are used in the solution-annealed condition with the following guaranteed minimum mechanical properties. All properties are verified through full testing in our in-house quality control laboratory and reported on the EN 10204 3.1 Mill Test Certificate.
| Property | Metric | Imperial |
|---|
| Tensile Strength (min.) | 621 MPa | 90,000 psi |
| Yield Strength (0.2% offset, min.) | 448 MPa | 65,000 psi |
| Elongation at break (50 mm, min.) | 25.0 % | 25.0 % |
| Reduction of Area (min.) | 45.0 % | 45.0 % |
| Hardness (Brinell, max.) | 293 HBW | 293 HBW |
| Charpy V-Notch Impact (−40 °C) | 34 J | 25 ft-lbs |
Physical and Thermal Properties of UNS S31803 (A182-F51)
The following physical and thermal properties of ASTM A182 Grade F51 (UNS S31803) are essential for design engineers to perform stress analysis, thermal modelling, and finite element analysis (FEA). Values are given for the solution-annealed condition at or near room temperature (20 °C / 68 °F) unless otherwise stated.
| Property | Value (SI) | Value (Imperial) |
|---|
| Density | 7.80 g/cm³ | 0.282 lb/in³ |
| Elastic Modulus (Young's Modulus) | 200 GPa | 29.0 × 10⁶ psi |
| Shear Modulus | 80 GPa | 11.6 × 10⁶ psi |
| Poisson's Ratio | 0.30 | 0.30 |
| Thermal Conductivity (at 20 °C) | 19 W/(m·K) | 131 BTU·in/(hr·ft²·°F) |
| Specific Heat Capacity (at 20 °C) | 500 J/(kg·K) | 0.12 BTU/(lb·°F) |
| Coefficient of Thermal Expansion (20–100 °C) | 13.0 × 10⁻⁶ /°C | 7.2 × 10⁻⁶ /°F |
| Coefficient of Thermal Expansion (20–300 °C) | 13.5 × 10⁻⁶ /°C | 7.5 × 10⁻⁶ /°F |
| Electrical Resistivity (at 20 °C) | 0.085 µΩ·m | 33.5 µΩ·in |
| Magnetic Permeability | Slightly ferromagnetic (µ ≈ 1.5–2.0) | Slightly ferromagnetic (µ ≈ 1.5–2.0) |
| Melting Range | 1,350–1,440 °C | 2,460–2,625 °F |
Design Note: The thermal expansion coefficient of UNS S31803 (13.0 × 10⁻⁶ /°C) is lower than 316L austenitic stainless steel (~16.5 × 10⁻⁶ /°C), which is important when designing mixed-material assemblies. Its thermal conductivity (approximately 19 W/m·K) is also slightly higher than that of standard austenitic grades, which provides advantages in heat exchanger and cooling system applications.
International Standards Equivalents for A182-F51 / UNS S31803
ASTM A182 Grade F51 is known by different designations across international standards. The table below provides the complete cross-reference mapping used by procurement teams, engineers, and inspection bodies in different regions. All designations refer to the same nominal 22Cr-5Ni-3Mo-N duplex stainless steel alloy.
| Standard / Country | Designation | Standard Body / Document |
|---|
| USA (Forgings) | A182 Grade F51 | ASTM A182 / ASME SA-182 |
| USA (Plate, Sheet, Strip) | A240 Type S31803 | ASTM A240 |
| USA (Bar) | A276 / A479 Type S31803 | ASTM A276 / A479 |
| USA (Pipe) | A790 Grade S31803 | ASTM A790 |
| UNS (USA — Original) | UNS S31803 | SAE / ASTM Unified Numbering System |
| UNS (USA — Revised, tighter N) | UNS S32205 | SAE / ASTM Unified Numbering System |
| Europe (Material Number) | 1.4462 | EN 10027-2 |
| Europe (Chemical Symbol) | X2CrNiMoN22-5-3 | EN 10088-3, EN 10272 |
| Germany | DIN 1.4462 / X2CrNiMoN22-5-3 | DIN EN 10088 |
| United Kingdom | 318S13 | BS 970 |
| Sweden | SAF 2205 / SS 2377 | SS (Swedish Standard) |
| France | Z3CND22-05Az | AFNOR NF A 35-574 |
| Japan | SUS329J3L | JIS G 4303 / JIS G 4318 |
| China | 022Cr22Ni5Mo3N | GB/T 20878, GB/T 1220 |
| Russia | 03Х22Н5М3 | GOST R 50 Sheets |
| Common Trade Names | 2205, SAF 2205, Uranus 45N, Ferralium 255 (≠) | Various manufacturers |
Note: "Ferralium 255" is a different alloy (UNS S32550) and should not be confused with 2205/F51. All Jiangsu Liangyi A182-F51 forgings are certified to both S31803 and S32205 compositional requirements where applicable, and can be cross-certified to EN 1.4462 on request.
A182-F51 vs 316L vs A182-F53 — Material Comparison
The table below compares ASTM A182 Grade F51 (UNS S31803) with 316L austenitic stainless steel and the higher-grade A182-F53 (UNS S32750) super duplex, which can help engineers and procurement teams choose the right alloy for their application.
| Property | 316L Stainless Steel | A182-F51 / UNS S31803 | A182-F53 / UNS S32750 |
|---|
| Microstructure | Austenitic | Duplex (50% A + 50% F) | Super Duplex (50% A + 50% F) |
| Typical Cr-Ni-Mo (wt%) | 17-12-2.5 | 22-5-3 | 25-7-4 |
| Min. Yield Strength | ~170 MPa | 448 MPa | 550 MPa |
| Min. Tensile Strength | ~485 MPa | 621 MPa | 795 MPa |
| PREN (Pitting Resistance) | ~24 | ≥ 34 | ≥ 41 |
| Chloride SCC Resistance | Low | Good | Excellent |
| ASTM Standard (Forgings) | A182-F316L | A182-F51 | A182-F53 |
| UNS Designation | S31603 | S31803 / S32205 | S32750 |
| Typical Use Case | General corrosion service | Oil & gas, chemical, marine | Extreme sour / offshore service |
| Relative Cost | Moderate | Moderate-High | High |
Note: S31803 (older) and S32205 (newer, slightly tighter N range) are both commonly called A182-F51 or "2205 duplex." They are interchangeable in most specifications.
UNS S31803 vs UNS S32205 — What Is the Difference?
Engineers and procurement specialists frequently inquire about the difference between UNS S31803 and UNS S32205. Both grades belong to the same 2205 duplex stainless steel alloy family and are often used interchangeably, but there are subtle yet important compositional differences that engineers need to be aware of.
| Parameter | UNS S31803 (Original) | UNS S32205 (Revised) |
|---|
| Year Introduced | 1980s (original 2205 designation) | ~2001 (refined compositional limits) |
| Chromium (Cr) range | 21.0 – 23.0 wt% | 22.0 – 23.0 wt% (tighter lower limit) |
| Nitrogen (N) range | 0.08 – 0.20 wt% | 0.14 – 0.20 wt% (tighter lower limit) |
| Molybdenum (Mo) range | 2.50 – 3.50 wt% | 2.50 – 3.50 wt% (unchanged) |
| Guaranteed minimum PREN | ≥ 34 (at minimum composition) | ≥ 36 (guaranteed by tighter N & Cr floors) |
| ASTM A182 Forging Grade | Both covered under A182 Grade F51 |
| EN / DIN Equivalent | Both correspond to EN 1.4462 / X2CrNiMoN22-5-3 |
| Interchangeability in Practice | Interchangeable in almost all specifications. Most commercially available material already meets S32205 limits. |
Why was S32205 introduced? In the 1990s, metallurgists found that S31803 heats with nitrogen content near the lower end of the range (0.08–0.13%) sometimes exhibited insufficient corrosion resistance in harsh service conditions.The UNS S32205 designation was therefore established to set a higher minimum nitrogen content, ensuring consistently higher PREN values and more reliable corrosion performance.
Jiangsu Liangyi practice: All our A182-F51 forgings are made to meet both S31803 and S32205 compositional requirements simultaneously. Our actual nitrogen content consistently falls within the S32205 range (0.14–0.20 %). We recommend that customers specify "UNS S31803 / S32205 dual-certified" in their purchase requisitions . This is standard practice among major oil and gas operators, and it serves as our default supply condition.
ASTM A182 Grade F51 / UNS S31803 — Limitations and Application Cautions
While ASTM A182 Grade F51 is a widely used engineering alloy, engineers must be aware of the following inherent metallurgical limitations and application boundaries. Knowing these constraints is essential for safe and reliable equipment design.
1. Sigma Phase Precipitation (> 300 °C / 570 °F)
Sigma (σ) phase is a hard, brittle, chromium-molybdenum-rich intermetallic compound that precipitates in duplex stainless steels at elevated temperatures. It is the most important limitation of A182-F51:
- Sigma phase forms most rapidly in the range of 700–900 °C (1290–1650 °F), but can also start to form with prolonged exposure above approximately 300 °C (570 °F).
- Its formation severely reduces toughness and ductility, and depletes chromium/molybdenum from the matrix — reducing corrosion resistance
- For this reason, A182-F51 is not recommended for continuous service above 300 °C (570 °F)
- Sigma phase can be dissolved by re-solution annealing at 1,050–1,100 °C followed by rapid quenching, restoring full properties
For higher-temperature service, consider austenitic grades (e.g., 316H, 321H, 347H) or nickel-base alloys.
2. Low-Temperature Toughness Limit (< −40 °C / −40 °F)
The ferrite phase experiences a ductile-to-brittle transition at low temperatures. Following are main facts:
- ASTM A182 requires a minimum Charpy V-notch impact of 34 J (25 ft-lbs) at −40 °C — this is the practical lower limit for most design codes
- Impact energy drops sharply below −50 °C (−58 °F), making F51 unsuitable for cryogenic service or very cold arctic environments
- For service below −50 °C, fully austenitic grades (304L, 316L) or nickel-alloyed ferritic steels should be chosen instead
3. Hydrogen Embrittlement Risk
The ferrite phase in A182-F51 is prone to hydrogen-induced damage under certain conditions:
- Cathodic protection (CP) environments: In subsea and offshore applications, too much cathodic protection (more negative than about −900 mV vs.. Ag/AgCl) can cause hydrogen absorption into the ferrite phase, resulting in hydrogen embrittlement.Always adhere to the CP potential limits for duplex stainless steels specified in DNVGL-RP-B401.
- Sour (H₂S-containing) service: A182-F51 is approved for sour service per NACE MR0175 / ISO 15156-3, subject to specified limits on H₂S partial pressure, temperature (< 232 °C), and maximum hardness (≤ 36 HRC).Always verify that it meets your project’s specific sour service requirements.
- Dry hydrogen service at elevated temperature: Not recommended above approximately 230 °C (450 °F) without specific qualification
4. 475 °C Embrittlement (885 °F Embrittlement)
Duplex stainless steels may suffer from spinodal decomposition of the ferrite phase in the temperature range 400–500 °C (750–930 °F), known as "475 °C embrittlement" or "885 °F embrittlement":
- Results in significant increase in hardness and yield strength, but severe loss of ductility and toughness
- Develops progressively over hundreds to thousands of hours at temperature
- This is an additional reason why continuous service above 300 °C is not recommended (leaving a safety margin below 400 °C)
- Fully reversible by solution annealing at 1,050–1,100 °C + rapid quench
A182-F51 Service Limit Summary:
✔ Maximum continuous service temperature: 300 °C (570 °F)
✔ Minimum service temperature (Charpy guarantee): −40 °C (−40 °F)
✔ Seawater CPTT (critical pitting): ≈ 25 °C (PREN ≥ 34)
✔ Sour service: Permitted per NACE MR0175 / ISO 15156-3 within defined limits
✔ Subsea CP potential limit: −900 mV vs. Ag/AgCl (per DNVGL-RP-B401)
Quality Assurance and Inspection Standards
At Jiangsu Liangyi, we implement a rigorous ISO 9001:2015 quality management system to make sure every A182-F51 forging meets the highest industry standards. Our inspection processes meet all international standards including ASTM, DIN, EN, JIS, API 6A, NACE MR0175, and NACE MR0103.
Advanced In-House Testing Capabilities
- Non-Destructive Testing (NDT): It includes visual inspection, dimensional testing, ultrasonic testing (UT), dye penetrant testing (PT), magnetic particle testing (MT), and radiographic testing (RT)
- Chemical Analysis: Optical emission spectrometry (OES) and carbon/sulfur analysis
- Mechanical Testing: Tensile testing, hardness testing, Charpy impact testing, and fatigue testing
- Metallographic Examination: Grain size analysis, microstructure evaluation (austenite/ferrite phase balance), and inclusion rating
- Corrosion Testing: Salt spray testing, pitting corrosion testing (ASTM G48), and stress corrosion cracking (SCC) testing
Certification and Full Material Traceability
Each finished A182-F51 forging is clearly marked with the purchaser's part number, purchase order number, individual identification number, and heat number to provide complete material traceability from raw material to finished product. We provide:
- Mill Test Certificates (MTC) EN 10204 3.1 are provided as standard with every shipment
- EN 10204 3.2 certificates with independent third-party inspection are available on request
- Third-party inspectors accepted: SGS, Bureau Veritas (BV), TÜV, Lloyd's Register, ABS, and others
- NACE MR0175 / ISO 15156 compliance documentation for sour service applications
- API 6A documentation package are provided for wellhead and Christmas tree equipment
Global Service & Delivery
Jiangsu Liangyi has been supplying high-quality A182-F51 forgings to customers in more than 50 countries across 6 continents for over 25 years. We offer full services to meet the needs of our international clients around the world.
Global Market Coverage
- North America: United States, Canada and Mexico are all in North America
- Europe: Germany, France, United Kingdom, Italy, Spain, Netherlands, Norway, Sweden, Denmark, Finland, Belgium, Switzerland and Austria are all in Europe.
- Middle East: Saudi Arabia, the United Arab Emirates, Qatar, Kuwait, Oman, Iran and Iraq are all in Middle East
- Asia Pacific: Japan, South Korea, Australia, New Zealand, Singapore, Malaysia, Indonesia, Thailand, Vietnam and India are all in Asia Pacific.
- Africa: South Africa, Nigeria, Egypt, Algeria, Angola and Morocco are all in Africa.
- South America: Brazil, Argentina, Chile, Peru, Colombia and Venezuela are all in South America.
International Logistics & Delivery
- Shipping Options: Sea freight (FCL/LCL), air freight, and express delivery (DHL, FedEx, UPS, TNT)
- Packaging: Standard export packaging with wooden crates, anti-rust oil, and waterproof wrapping
- Customs Clearance Assistance: Commercial invoice, packing list, bill of lading, certificate of origin, Mill Test Certificate
- Delivery Terms: EXW, FOB Shanghai, CIF, CFR, DAP, and DDU are available
- Lead Time: it is 2–4 weeks for standard products; 4–6 weeks for custom products; expedited production are also available.
Global Customer Support
- Multi-language support: English, Spanish, French, and German
- 24/7 technical support and after-sales service
- Custom engineering and design assistance from our experienced technical team
- On-site inspection and installation support are available upon request.
A182-F51 / UNS S31803 Forging Delivery Case Studies
Following are real cases that Jiangsu Liangyi has helped international clients with specific engineering and logistics problems. You can compare each case's full technical and commercial data to your own needs.
Customer Pain Point: The first European supplier sent 11" × 3M rated wellhead spool body forgings that failed a dimensional inspection. 14 out of 41 pieces had an OD that was too large, by +3.8 mm.This put the schedule for finishing the offshore rig in serious danger, since it cost more than USD 85,000 a day to keep it running.The EPC contractor needed a replacement supply in less than 25 working days, with full EN 10204 3.2 MTC and SGS witnessed inspection.
Component Specifications: - Wellhead Spool Bodies (×24): OD 520 mm × ID 280 mm × L 410 mm; wall 120 mm; tolerance is ±0.5 mm on bore; weight is 285 kg/pc
- Casing Head Flanges (×12): OD 660 mm × ID 346 mm × L 180 mm; 11" 3M API 6A flange face; weight is 198 kg/pc
- Tubing Head Adapters (×5): OD 480 mm × ID 200 mm × L 310 mm; weight is 224 kg/pc
- All forged on our 6,300T press; solution annealed at 1,075 °C ± 5 °C; water quenched
- Charpy V-notch at −40 °C: avg 68 J (min. required 34 J) — nearly 2× the requirement
- Hardness: 210–228 HBW across all pieces (max. 293 HBW per ASTM A182)
- Full UT (ASTM A388), PT (ASTM E165), and dimensional report per customer DXF drawings
✔ Outcome: All 41 pieces successfully passed SGS third-party inspection at our facility on Day 17 and were air-freighted to Dammam on Day 19, with zero dimensional non-conformances.Rig completion was finished on schedule with no delays.The customer has since placed 3 repeat orders, totalling 62 tons.
Customer Pain Point: The German engineering firm required heat exchanger tube sheets with bore hole patterns machined to H7 tolerance (±0.018 mm), along with ferrite content verification (40–60% ferrite, tested per ASTM E562 point‑count method) for every component. Previous suppliers could not guarantee consistent ferrite balance, leading to repeated rejections during TÜV inspection.The client needed a supplier with in‑house metallographic testing capability and a TÜV‑approved quality assurance plan (QAP).
Component Specifications: - Heat Exchanger Tube Sheets (×16): OD 1,240 mm × thickness 120 mm; 847× bore holes Ø 25.4 mm at H7 tolerance; weight is 345 kg/pc; forged disc form
- Blind Flanges DN 500 PN 40 (×8): OD 715 mm × thickness 95 mm; EN 1092-1 Type 05; weight is 183 kg/pc
- Weld Neck Flanges DN 300 PN 63 (×4): OD 510 mm; bore 336 mm; L 280 mm; weight is 127 kg/pc
- Solution anneal: 1,080 °C / 45 min / water quench — verified by furnace chart per piece
- Ferrite content: 48–54 % (all pieces) — reported on MTC per ASTM E562
- Tube hole boring: CNC bored in-house; CMM report is supplied for each tube sheet
- Intergranular corrosion test per ASTM A262 Practice E (Strauss Test) — passed on all heats
- Pitting corrosion test per ASTM G48 Method A at 22 °C — no pitting observed
✔ Outcome: All 28 pieces passed TÜV Rheinland witnessed inspection on the first attempt.EN 10204 3.2 certificates were issued accordingly. The client submitted their PED Declaration of Conformity directly referencing our Mill Test Certificates. Client feedback:“The ferrite balance data and CMM reports were more comprehensive than any previous supplier — domestic or international.”
We have since become a preferred vendor in their duplex stainless steel procurement framework.
Customer Pain Point: An Abu Dhabi-based desalination contractor required seamless rolled rings with an outer diameter of up to 2,800 mm for high-pressure seawater reverse osmosis pump casings. A main requirement was verified PREN ≥ 36 (meeting UNS S32205 specifications) for each individual heat — not just nominal values on the MTC. Additionally, ASTM G48 Method C critical pitting temperature (CPT) testing at 25 °C was mandatory to confirm reliable seawater corrosion resistance. Two previous suppliers from South Korea and India were unable to provide per-heat CPT test data.Any pitting failure in seawater service would have necessitated a full pump overhaul, resulting in extremely high costs and downtime.
Component Specifications: - Seamless Rolled Rings — Pump Casing Shells (×12): OD 2,800 mm × ID 2,540 mm × H 380 mm; wall thickness is130 mm; weight is 2,180 kg/pc; rolled on our 5M CNC ring rolling machine
- Pump Casing End Discs (×8): OD 2,750 mm × thickness 160 mm; weight is 2,430 kg/pc; open die forged on 6,300T press
- All from 2 heats — Heat A (JL-H25061) and Heat B (JL-H25062) — with full heat traceability
- Actual N content: Heat A 0.168 %, Heat B 0.172 % — both within S32205 range (0.14–0.20 %)
- Calculated PREN: Heat A = 37.4, Heat B = 37.8 — both exceed S32205 minimum of 36
- Solution anneal: 1,085 °C / 60 min / immediate water quench; austenite/ferrite balance 49 %/51 % (Heat A) and 51 %/49 % (Heat B)
- ASTM G48 Method C CPT test: No pitting at 25 °C on 5 test specimens per heat — passed
- UT per ASTM A388 Level C; PT per ASTM E165 — all pieces accepted
- Sea freight from Shanghai to Jebel Ali port; wooden crate + VCI film + desiccant packing
✔ Outcome: Bureau Veritas (BV) witnessed all testing at our facility over a 3-day period.EN 10204 3.2 certification and ASTM G48 CPT test reports were issued accordingly.
All 20 pieces achieved zero non-conformances.The desalination contractor confirmed these were the first duplex forgings they had ever received with per-heat CPT test data in their entire project history. The pump casings entered service in Q1 2026 with no corrosion incidents reported.We have already received a repeat enquiry for Phase 2 expansion, with an estimated volume of 48 tons.
Order references and heat numbers are provided for internal traceability. Customer names are withheld per confidentiality agreements. Full MTCs and test reports for these orders are available to qualified buyers upon request under NDA.
Frequently Asked Questions — ASTM A182 Grade F51 / UNS S31803 Forgings
What is the difference between A182-F51 and 2205 duplex stainless steel?
A182-F51 and 2205 are essentially the same alloy.A182-F51 is the designation for forged products under the ASTM A182 standard, while “2205” is the common industry name for this duplex stainless steel (covering UNS S31803 and the improved S32205 variant).
Both refer to a 22Cr‑5Ni‑3Mo‑0.15N duplex grade with identical chemical and mechanical properties.The forging-specific designation is defined in ASTM A182 / ASME SA‑182.
What is the maximum size of A182-F51 forgings you can produce?
We can produce A182-F51 forgings up to 30 metric tons in weight. For seamless rolled rings, the maximum diameter is 6 meters (6,000 mm). For forged bars, the maximum diameter is 2 meters (2,000 mm). For forged shafts, the maximum length is 15 meters.
What certifications do you provide for A182-F51 forgings?
We provide Mill Test Certificates (MTC) EN 10204 3.1 as standard with every shipment. EN 10204 3.2 certificates with independent third-party inspection endorsement are available upon request. We are certified to ISO 9001:2015 and API 6A, and all materials meet NACE MR0175 and NACE MR0103 for sour service where needed. We work with SGS, BV, TÜV, Lloyd's Register, and ABS.
Can you provide custom machining for A182-F51 forgings?
Yes. We offer full in-house CNC machining services. A182-F51 forgings can be supplied in rough-machined, semi-finished, or fully finished condition according to client's drawings, specifications, and dimensional tolerances. We can also assist with engineering reviews and DFM (design for manufacturability) feedback.
What is the typical lead time for A182-F51 forgings?
The normal lead time for standard A182-F51 forgings is 2–4 weeks. For more custom parts or larger quantities, the lead time is normally 4–6 weeks. We can also speed up production for urgent orders.Please contact us for details.
Do you supply A182-F51 forgings to the oil and gas industry?
Yes. A182-F51 is one of the best choice material for the oil and gas industry. We supply a wide range of A182-F51 parts for wellhead equipment, subsea systems, valves, pipeline flanges, and BOPs to major oil and gas operators in the Middle East, North America, and South America. All our oil and gas forgings meet API 6A and NACE MR0175 / NACE MR0103 standards.
What heat treatment is applied to A182-F51 forgings?
A182-F51 forgings are solution annealed at 1,050–1,100 °C (1,920–2,010 °F) followed by rapid quenching in water. This process dissolves all secondary phases (such as sigma phase), forms an optimally balanced 50:50 austenite‑ferrite microstructure, and provides the best combination of mechanical properties and corrosion resistance.Heat treatment is performed in computer‑controlled furnaces with complete temperature traceability.
Can you provide third-party inspection services?
Yes. We work with all major third-party inspection agencies including SGS, Bureau Veritas (BV), TÜV, Lloyd's Register, and ABS. We can arrange inspection and testing to be witnessed by your chosen third-party inspector, and we can provide EN 10204 3.2 certificates with their endorsement.
What is the minimum order quantity for A182-F51 forgings?
We do not enforce a strict minimum order quantity (MOQ).We can supply small volumes for testing, as well as full-scale production batches.Please note that unit prices are higher for smaller quantities due to setup and heat treatment costs.Contact us for a detailed quotation tailored to your specific requirements.
How does A182-F51 compare to 316L stainless steel in terms of strength and corrosion resistance?
ASTM A182 Grade F51 (UNS S31803) has about 2.6 times the yield strength of 316L (448 MPa vs. a typical ~170 MPa minimum).It also gets a much higher PREN ≥ 34, compared to only ~24 for 316L.
F51 provides significantly better resistance to pitting, crevice corrosion, and chloride-induced stress corrosion cracking (SCC) — a common failure mode for 316L in seawater and sour oil & gas service.
The trade-off is slightly lower toughness at extremely low temperatures, and stricter welding controls to prevent the formation of harmful secondary phases.
Do you export A182-F51 forgings to my country?
We export A182-F51 forgings to more than 50 countries around the world, including the United States, Canada, Germany, United Kingdom, France, Saudi Arabia, United Arab Emirates, Australia, Japan, South Korea, Brazil, and many other countries. Please contact us with your location and requirements for a detailed quotation including shipping and delivery time.