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- SS SMLS PIPE 2507 ASTM A790
- SS SMLS PIPE 2205 ASTM A790
- SS SMLS PIPE S31803 ASTM A790
- SS SMLS PIPE 904L ASTM A240
- SS SMLS PIPE TP321 ASTM A312
- SS SMLS PIPE TP310S ASTM A312
- SS SMLS PIPE TP316Ti ASTM A312
- SS SMLS PIPE TP316L ASTM A312
- SS SMLS PIPE TP316 ASTM A312
- SS SMLS PIPE TP304L ASTM A312
- SS SMLS PIPE TP304 ASTM A312
S31803 Duplex Stainless Steel Pipe - China Factory Suppliers with Fast Delivery and Stock Availability
Introduction
ASTM A790/A790M S31803 duplex stainless steel pipes combine austenitic and ferritic microstructures, delivering twice the strength of 316L with exceptional resistance to chloride-induced stress corrosion cracking (SCC). Ideal for harsh offshore, chemical, and marine applications, this alloy balances cost-efficiency with premium performance.
Key Features
Dual-Phase Strength
Yield strength ≥450 MPa, nearly double conventional stainless steels (e.g., 304/316), reducing wall thickness and material costs.
Enhanced Corrosion Resistance
21%-23% Cr, 2.5%-3.5% Mo, and 4.5%-6.5% Ni combat pitting/crevice corrosion in seawater, acids, and sour gas (H₂S) environments (PREN ≥35).
Thermal Stability
Performs reliably from -50°C to 300°C (-58°F to 572°F), suitable for subsea and high-pressure systems.
Material Specification
Standard
ASTM A790/A790M
O.D
1/8" NB TO 32" NB, (10.29MM-812.80MM), (Customization Available)
W.T
SCH 10S, SCH 40S, SCH 80S, SCH160, SCH XXS (Customization Available)
Application
- Oil & Gas Pipelines (Including Sour Service)
- Chemical & Petrochemical Processing
- Desalination & Water Treatment Plants
- Marine & Offshore Structures
- Power Plants (Including Flue Gas Desulfurization)
- Pulp & Paper Industry
- Heat Exchangers & Condensers
End
Plain End, Beveled End, Threaded
Processing
Cut-to-length; Polishing.
Inspection
- 100% PMI (Positive Material Identification) Tested
- EN 10204 3.1/3.2 Mill Test Certificate
- Third-Party Inspection Accepted (SGS, BV, TUV, etc.)
- Ultrasonic Testing (UT) / Eddy Current Testing (ECT) Available
- Hardness, Tensile, and Impact Testing as per ASTM Standards
Delivery Condition
Cold Drawn, Annealed and Pickled/ Polished /Bright Annealed/ Sand blasting/ Shot Blasting.
Marking
All SS SMLS Pipes are marked as follows: Standard, Grade, OD, Thickness, Length, Heat No. (Or as per the customer’s request)
Packing
Packed in Wooden Boxes, plywood cases, Steel Strips Bundled, or as per Customers Requests
Specials
Sizes and Specifications other than above can be customized on request.
Specification parameters
S31803 chemical composition
| HEAT NO. | CHEMICAL COMPOSITION (%) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| C | Mn | P | S | Si | Ni | Cr | Mo | N | ||
| STAND. | MIN. | - | - | - | - | - | 4.50 | 21.00 | 2.50 | 0.08 |
| MAX. | 0.03 | 2.00 | 0.03 | 0.020 | 1.00 | 6.50 | 23.00 | 3.50 | 0.20 | |
S31803 Mechanical Properties
| Mechanical Properties | |||||
|---|---|---|---|---|---|
| Grade | Tensile Strength (MPa) min | Yield Strength 0.2% Proof (MPa) min | Elongation (% in 50mm) min | Hardness | |
| HRW | HRC | ||||
| S31803 | 620 | 450 | 25 | 290 | 30 |
Equivalent Grades - (ASTM A790/A790M S31803 Equivalent Grades)
| ASTM A790/A790M S31803 (UNS S31803) Equivalent Grades | ||||||
|---|---|---|---|---|---|---|
| ISO | EN (Europe) | DIN (Germany) | JIS (Japan) | GB (China) | UNS (USA) | AISI/SAE |
| X2CrNiMoN22-5-3 (ISO 15510) | 1.4462 (EN 10088-2) | X2CrNiMoN22-5-3 (DIN 17440) | SUS 329J3L (JIS G3463) | 022Cr22Ni5Mo3N (GB/T 21833) | S31803 | Duplex 2205 (Commercial Name) |
ASTM A312/A312M Standard Cold Machining size Deviation Permitted
| ASTM A312/A312M-09 Standard Permitted Tolerance of WT and OD | |||||
|---|---|---|---|---|---|
| Nominal Outside Diameter | Allowable deviation | Nominal wall thickness | Allowable deviation | ||
| 1/8”—1 1/2“ | (10.29—48.26) | +0.4 -0.8 | 1/8”—1 1/2“ | (10.29-73.03) all of t | +20 -12.5 |
| >1 1/2“—4” | (48.26—114.3) | ±0.8 | 3“—18” | (88.9-457.2) t/D=5% | +22.5 -12.5 |
| >4”—8" | (114.3—219.08) | +1.6 -0.8 | 3“—18” | (88.9-457.2) t/D>5% | +15 -12.5 |
| >8“—18" | (219.08—457.2) | +2.4 -0.8 | ≥20" | =508 t of wld pipe | +17.5 -12.5 |
| >18”—26“ | (457.2—660.4) | +3.2 -0.8 | ≥20" | =508 t/D=5% | +22.5 -12.5 |
| >26”—34” | (660.4—863.6) | +4.0 -0.8 | ≥20" | =508 t/D>5% | +15 -12.5 |
| >34“—48" | (863.6—1219.2) | +4.8 -0.8 | - | - | - |
| Thin wall pipe (t/D=3%) ovality condition: Any cross section in a steel pipe Dmax Dmin=1.5%nominal,and(Dmax Dmin)/ 2 conforms to the stipulated diameter tolerance range. | |||||
Comparison Table Of American Standard Dimensions - (ANSI B36.19 & ANSI B36.10) (This data refers to ASTM A312)
| OD DN | IN | OD MM | ANSI B36.19 | ANSI B36.10 | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Nominal diameter in inches | ||||||||||||||||||||
| 5s | 10s | Sched.40s | Sched.40 | Sched.80s | Sched.80 | 10 | 20 | 30 | Standard | |||||||||||
| mm | Kg/m | mm | Kg/m | mm | Kg/m | mm | mm | Kg/m | mm | mm | Kg/m | mm | Kg/m | mm | Kg/m | mm | Kg/m | |||
| 6 | 1/8" | 10.29 | - | - | 1.24 | 0.281 | 1.73 | 371 | 1.73 | 2.41 | 0.467 | 2.41 | - | - | - | - | - | - | 1.73 | 0.371 |
| 8 | 1/4" | 13.72 | - | - | 1.65 | 0.499 | 2.24 | 0.644 | 2 | 3.02 | 0.809 | 3.02 | - | - | - | - | - | - | 2.24 | 0.644 |
| 10 | 3/8" | 17.14 | - | - | 1.65 | 0.64 | 2.31 | 0.858 | 2.31 | 3.2 | 1.118 | 3.2 | - | - | - | - | - | - | 2.31 | 0.858 |
| 15 | 1/2" | 21.34 | 1.65 | 0.814 | 2.11 | 1.016 | 2.77 | 1.26 | 2.77 | 3.73 | 1.62 | 3.73 | - | - | - | - | - | - | 2.77 | 1.26 |
| 20 | 3/4" | 26.67 | 1.65 | 1.034 | 2.11 | 1.298 | 2.87 | 1.68 | 2.87 | 3.91 | 2.19 | 3.91 | - | - | - | - | - | - | 2.87 | 1.68 |
| 25 | 1" | 33.4 | 1.65 | 1.312 | 2.77 | 2.125 | 3.38 | 2.5 | 3.38 | 4.55 | 3.23 | 4.55 | - | - | - | - | - | - | 3.36 | 2.5 |
| 32 | 1 1/4" | 42.16 | 1.65 | 1.674 | 2.77 | 2.732 | 3.56 | 3.38 | 3.56 | 4.85 | 4.46 | 4.85 | - | - | - | - | - | - | 3.56 | 3.38 |
| 40 | 1 1/2" | 48.26 | 1.65 | 1.926 | 2.77 | 3.155 | 3.68 | 4.05 | 3.68 | 5.08 | 5.4 | 5.08 | - | - | - | - | - | - | 3.68 | 4.05 |
| 50 | 2" | 60.32 | 1.65 | 2.424 | 2.77 | 3.992 | 3.91 | 5.43 | 3.91 | 5.54 | 7.47 | 5.54 | - | - | - | - | - | - | 3.91 | 5.43 |
| 65 | 2 1/2" | 73.02 | 2.11 | 3.747 | 3.05 | 5.345 | 5.16 | 8.62 | 5.16 | 7.01 | 11.4 | 7.01 | - | - | - | - | - | - | 5.16 | 8.62 |
| 80 | 3" | 88.9 | 2.11 | 4.585 | 3.05 | 6.557 | 5.49 | 11.28 | 5.49 | 7.62 | 15.25 | 7.62 | - | - | - | - | - | - | 5.49 | 11.28 |
| 90 | 3 1/2" | 101.6 | 2.11 | 5.272 | 3.05 | 7.526 | 5.74 | 13.56 | 5.74 | 8.08 | 18.62 | 8.08 | - | - | - | - | - | - | 5.74 | 13.56 |
| 100 | 4" | 114.3 | 2.11 | 5.945 | 3.05 | 8.496 | 6.02 | 16.06 | 6.02 | 8.56 | 22.29 | 8.56 | - | - | - | - | - | - | 6.02 | 16.06 |
| 125 | 5" | 141.3 | 2.77 | 9.639 | 3.4 | 11.74 | 6.55 | 21.76 | 6.55 | 9.52 | 30.92 | 9.52 | - | - | - | - | - | - | 6.55 | 21.76 |
| 150 | 6" | 168.28 | 2.77 | 11.514 | 3.4 | 14.037 | 7.11 | 28.23 | 7.11 | 10.97 | 42.52 | 10.97 | - | - | - | - | - | - | 7.11 | 28.23 |
| 200 | 8" | 219.08 | 2.77 | 15.049 | 3.76 | 20.334 | 8.18 | 42.49 | 8.18 | 12.7 | 64.57 | 12.7 | - | - | 6.35 | 33.28 | 7.04 | 36.8 | 8.18 | 42.4 |
| 250 | 10" | 273.05 | 3.4 | 23.028 | 4.19 | 28.29 | 9.27 | 60.24 | 9.27 | 12.7 | 81.46 | 15.09 | - | - | 6.35 | 41.7 | 7.8 | 51 | 9.27 | 60.24 |
| 300 | 12" | 323.85 | 3.96 | 31.806 | 4.57 | 36.633 | 9.52 | 73.76 | 10.31 | 12.7 | 97.36 | 17.48 | - | - | 6.35 | 49.68 | 8.38 | 65.14 | 9.52 | 73.76 |
| 350 | 14" | 355.6 | 3.98 | 34.99 | 4.78 | 42.102 | 9.52 | - | 11.13 | - | - | 19.05 | 6.35 | 54.63 | 7.92 | 67.98 | 9.52 | 81.21 | 9.52 | 81.21 |
| 400 | 16" | 406.4 | 4.19 | 42.35 | 4.78 | 48.22 | 9.52 | - | 12.7 | - | - | 21.44 | 6.35 | 62.58 | 7.92 | 77.9 | 9.52 | 93.13 | 9.52 | 93.18 |
| 450 | 18" | 457.2 | 4.19 | 47.7 | 4.78 | 54.3 | 9.52 | - | 14.27 | - | - | 23.82 | 6.35 | 70.5 | 7.92 | 87.8 | 11.13 | 122.12 | 9.52 | 105.05 |
| 500 | 20" | 508 | 4.77 | 60.32 | 5.54 | 69.766 | 9.52 | - | 15.09 | - | - | 26.19 | 6.35 | 78.47 | 9.52 | 116.97 | 12.7 | 155 | 9.52 | 116.97 |
| 550 | 22" | 558.8 | 4.77 | - | 5.54 | - | 9.52 | - | - | - | - | 28.58 | 6.35 | 86.42 | 9.52 | 128.89 | 12.7 | 170.86 | 9.52 | 128.89 |
| 600 | 24" | 609.6 | 5.54 | 84.1 | 6.35 | 96.215 | 9.52 | - | 17.48 | - | - | 30.96 | 6.35 | 96.215 | 9.52 | 140.8 | 14.7 | 209.54 | 9.52 | 140.81 |
| 650 | 26" | 660.4 | - | - | - | - | 9.52 | - | - | - | - | - | 7.92 | 127.58 | 12.7 | 202.65 | - | - | 9.52 | 152.73 |
| 700 | 28" | 711.2 | - | - | - | - | 9.52 | - | - | - | - | - | 7.92 | 137.52 | 12.7 | 218.54 | 15.88 | 271.94 | 9.52 | 164.65 |
| 750 | 30" | 762 | 6.35 | 120.59 | 7.92 | 147.45 | 9.52 | - | - | - | - | - | 7.92 | 147.45 | 12.7 | 234.44 | 15.88 | 291.81 | 9.52 | 176.57 |
| 800 | 32" | 812 | - | - | - | - | 9.52 | - | 17.48 | - | - | - | 7.92 | 157.39 | 12.7 | 250.33 | 15.88 | 311.67 | 9.52 | 188.5 |
| 850 | 34" | 863.6 | - | - | - | - | 9.52 | - | 17.48 | - | - | - | 7.92 | 167.32 | 12.7 | 266.22 | 15.88 | 331.54 | 9.52 | 200.42 |
| 900 | 36" | 914.4 | - | - | - | - | 9.52 | - | 19.05 | - | - | - | 7.92 | 177.26 | 12.7 | 282.18 | 15.88 | 351.41 | 9.52 | 212.34 |
Frequently Asked Questions (FAQ)
1. What is ASTM A790 S31803 duplex stainless steel?
It is a standard specification for seamless and welded duplex stainless steel pipes. S31803 features a balanced microstructural mix of austenite and ferrite, providing high strength and exceptional corrosion resistance.
2. How does S31803 compare to standard 316L stainless steel?
S31803 duplex steel offers nearly double the yield strength (≥450 MPa) of 316L. It also provides significantly better resistance to pitting, crevice corrosion, and chloride-induced stress corrosion cracking (SCC).
3. What are the main applications for ASTM A790 S31803 pipes?
These pipes are widely used in critical environments, including oil and gas transmission pipelines, chemical and petrochemical processing plants, marine/offshore structures, desalination facilities, and pulp and paper manufacturing.
4. What is the temperature limit for S31803 pipes?
S31803 performs reliably within the temperature range of -50°C to 300°C (-58°F to 572°F). Exposure to temperatures above 300°C may lead to embrittlement of the duplex microstructures.
5. What quality testing is performed on these duplex pipes?
Pipes undergo 100% PMI testing, mechanical testing (tensile, yield, elongation, hardness, impact), and non-destructive testing such as Ultrasonic Testing (UT) or Eddy Current Testing (ECT), backed by EN 10204 3.1/3.2 certification.