Home > Steel Tubes > Duplex Steel Tubes > Duplex Steel UNS S31803 Tubes
Duplex Steel UNS S31803 Tubes Manufacturer & Supplier in India
Kalpataru Piping Solution is a trusted name in delivering high-performance duplex stainless steel products, with a strong focus on duplex steel tubes and advanced material grades like UNS S31803. Known for its excellent strength and corrosion resistance, S31803 material is widely used across industries that demand durability and long service life. As a leading supplier, Kalpataru Piping Solution ensures that every product meets strict quality standards while aligning with global specifications.
Duplex stainless steel S31803, also referred to as duplex 2205, offers a balanced combination of austenitic and ferritic structures, resulting in superior mechanical performance. The S31803 properties include high tensile strength, improved fatigue resistance, and excellent resistance to stress corrosion cracking. Additionally, the precise S31803 chemical composition enhances its performance in harsh environments, making it suitable for chemical processing, marine applications, and heat exchangers.
We provide detailed technical support, including information on S31803 mechanical properties, S31803 density, and other critical parameters to help customers make informed decisions. The material is often compared with other grades, and understanding the UNS S32205 vs S31803 difference is essential for selecting the right application. We also guide clients on UNS S31803 material specification to ensure compliance with project requirements.
With a commitment to quality and precision, Kalpataru Piping Solution continues to be a reliable partner for industries seeking premium-grade duplex stainless steel solutions.
Table of content
- Duplex Steel UNS S31803 Tubes Specifications
- Duplex Steel S31803 Tube Equivalent Standard Grade
- Duplex Steel UNS S31803 Tubes Chemical Composition
- Duplex Steel UNS S31803 Tubing Mechanical Properties
- Physical Properties of Duplex S31803 Tubes
- Duplex Steel UNS S31803 Tubes Price
- Duplex Steel UNS S31803 Tubes Size
- Why Choose Kalpataru Piping Solution
- S31803 vs S32205 — What is the Difference?
- Applications of Duplex Steel UNS S31803 Tubes
- Testing and Certification of Duplex S31803 Tubes
- Packing & Delivery of Duplex S31803 Tubes
- HSN Code of Duplex Steel S31803 Tubes
- FAQs About Duplex Steel UNS S31803 Tubes
Duplex Steel UNS S31803 Tubes Specifications
| Specification | Details |
| Standards | ASTM A789, ASTM A790 / ASME SA789, ASME SA790 |
| Size Range (NB) | 15 NB (1/2″) to 150 NB (6″) |
| OD Range | 6 mm to 219 mm |
| Wall Thickness | 0.5 mm to 20 mm |
| Schedule | SCH20, SCH30, SCH40, STD, SCH60, SCH80, XS, SCH120, SCH140, SCH160, XXS |
| Length | Single Random, Double Random & Custom Length |
| Type | Cold Drawn / Seamless / ERW / Welded / Capillary Tubes |
| End | Plain End, Beveled End, Threaded |
| Finish | Annealed & Pickled / Bright Annealed / Electropolished |
| Heat Treatment | Solution Annealed & Quenched |
| PREN Value | ≈ 35 (minimum) |
| MTR Certification | EN 10204 3.1 / EN 10204 3.2 |
| Testing | PMI, Hydrostatic Test, IGC Test (ASTM A262) |
Duplex Steel S31803 Tube Equivalent Standard Grade
Standard | Werkstoff Nr. | UNS | AISI | JIS | BS | EN | AFNOR |
Duplex 2205 | 1.4462 | S31803 / S32205 | 2205 | SUS 329J3L | 318S13 | X2CrNiMoN22-5-3 | Z2CND22-05Az |
Note: S32205 is often used interchangeably with S31803. S32205 specifies a higher minimum nitrogen content (0.14%) compared to S31803 (0.08–0.20%), which improves corrosion resistance and overall performance in demanding environments.
Duplex Steel UNS S31803 Tubes Chemical Composition
Element | Composition (%) |
Carbon (C) | 0.030 max |
Manganese (Mn) | 2.00 max |
Silicon (Si) | 1.00 max |
Phosphorus (P) | 0.030 max |
Sulfur (S) | 0.020 max |
Chromium (Cr) | 22.0 – 23.0 |
Molybdenum (Mo) | 3.0 – 3.5 |
Nickel (Ni) | 4.50 – 6.50 |
Nitrogen (N) | 0.14 – 0.20 |
Iron (Fe) | 63.72 min |
Duplex Steel UNS S31803 Pipe and Tube Types
Duplex Steel UNS S31803 Tubing Mechanical Properties
Property | Metric Value | Imperial Value |
Tensile Strength (UTS) | 620 MPa min | 90,000 Psi min |
Yield Strength (0.2% Offset) | 450 MPa min | 65,000 Psi min |
Elongation | 25% min | — |
Hardness | ≤ 290 HB | — |
Physical Properties of Duplex S31803 Tubes
Property | Value |
Density | 7.805 g/cm³ (0.285 lb/in³) |
Melting Point | 1420–1465°C (2588–2669°F) |
Elastic Modulus | 200 GPa |
Thermal Conductivity | 19 W/m·K |
Thermal Expansion | 13.0 μm/m°C (0–100°C) |
Specific Heat | 500 J/kg·K |
Duplex Steel UNS S31803 Tubes Price
The price of Duplex Steel UNS S31803 tubes varies depending on factors such as size, wall thickness, finish, and quantity required. Typically, S31803 material is priced higher than standard stainless steel due to its superior strength and corrosion resistance. On average, the cost may range between ₹400 to ₹900 per kg in India, but this is only an indicative range. For bulk orders or custom specifications, prices may vary based on market conditions and raw material costs. At Kalpataru Piping Solution, customers receive competitive pricing along with assured quality and compliance with international standards.
Duplex Steel UNS S31803 Tubes Size
Duplex stainless steel UNS S31803 tubes are available in a wide range of sizes to meet diverse industrial requirements. Standard size ranges include:
- Outer Diameter (OD): 6 mm to 219 mm
- Wall Thickness: 0.5 mm to 20 mm
- Length: Up to 6 meters (custom lengths available)
- Type: Seamless, Welded, ERW, Fabricated
These tubes are manufactured in accordance with global standards such as ASTM specifications, ensuring precise dimensions, high strength, and excellent durability. The versatility of duplex steel tubes makes them suitable for industries like oil & gas, chemical processing, and marine applications.
Why Choose Kalpataru Piping Solution
Kalpataru Piping Solution stands out as a reliable supplier of duplex stainless steel S31803 tubes due to its commitment to quality and customer satisfaction. The company offers:
- Premium-grade UNS S31803 material with full test certification
- Strict adherence to international quality standards
- Wide stock availability for quick delivery
- Competitive pricing with customized solutions
- Expert technical support for material selection and application
With a strong reputation in the industry, Kalpataru Piping Solution ensures that every product delivers excellent performance, making it a preferred choice for duplex steel requirements.
S31803 vs S32205 — What is the Difference?
Parameter | S31803 | S32205 |
Nitrogen (N) | 0.08–0.20% | 0.14–0.20% (tighter range) |
PREN | ≈ 34 | ≈ 35 |
Corrosion Resistance | Good | Slightly better (higher N floor) |
Interchangeability | – | Generally interchangeable in most applications |
Preferred Where | Flexibility in nitrogen range is acceptable | Higher corrosion resistance is specified |
Standard | ASTM A789 / A790 | ASTM A789 / A790 (higher N threshold) |
Note: In practice, most mills supply 2205 material to the S32205 chemistry (higher nitrogen) while certifying it as S31803 to meet both specifications. Always verify nitrogen content in the MTR.
Applications of Duplex Steel UNS S31803 Tubes
- Oil & Gas: S31803 tubes are widely used in subsea pipelines, downhole tubing, topside piping, and gas processing systems. With a minimum yield strength of 450 MPa, they allow reduced wall thickness compared to 316L, lowering structural weight in offshore applications. A PREN value of ≈35 ensures resistance to H₂S environments when specified under NACE MR0175.
- Chemical Processing: The duplex structure provides strong resistance to sulphuric, phosphoric, and organic acids. Common applications include heat exchanger tubes, evaporators, reactor tubing, and scrubber systems.
- Desalination: Used in seawater reverse osmosis (SWRO) systems and brine handling units. The combination of chromium, molybdenum, and nitrogen offers excellent resistance to chloride-induced corrosion.
- Marine & Shipbuilding: Ideal for seawater cooling systems, ballast water treatment, and marine heat exchangers where chloride exposure is constant.
- Pulp & Paper: Resistant to aggressive chemicals used in kraft pulping. Applied in digesters, bleach plant heat exchangers, and wash press tubing.
Testing and Certification of Duplex S31803 Tubes
All UNS S31803 tubes supplied by Kalpataru Piping Solution undergo strict quality checks:
- Positive Material Identification (PMI)
- Chemical Composition (Spectro Analysis)
- Mechanical Testing (Tensile, Yield, Elongation as per ASTM A370)
- Hardness Testing (Brinell/Rockwell)
- Hydrostatic Pressure Testing
- Intergranular Corrosion (IGC) Test – ASTM A262 Practice E
- Dimensional Inspection (OD, Thickness, Straightness)
- Visual Surface Inspection
- Non-Destructive Testing (UT / Eddy Current)
- Mill Test Certificates (EN 10204 3.1 / 3.2)
Packing & Delivery of Duplex S31803 Tubes
Duplex Steel UNS S31803 tubes are securely packed to prevent damage during transit. Tubes are bundled with plastic end caps, wrapped in waterproof material, and packed in wooden boxes or export-grade steel crates. Each product is clearly marked with grade (S31803), heat number, OD × thickness, length, and applicable standard.
Delivery Timeline: Typically 2–4 weeks from order confirmation, depending on size and quantity.
HSN Code of Duplex Steel S31803 Tubes
- 73049090 – Seamless tubes of other alloy steel
- 73069010 – Welded tubes of other alloy steel
Note: The correct HSN sub-code should be confirmed with your export/import documentation team based on the exact product type and shipment requirements.
FAQs About Duplex Steel UNS S31803 Tubes
UNS S31803 is a duplex stainless steel grade (commonly known as 2205) that combines austenitic and ferritic structures. It offers high strength, excellent corrosion resistance, and good weldability.
The S31803 properties include high tensile strength, good fatigue resistance, excellent resistance to stress corrosion cracking, and strong performance in chloride environments.
S31803 duplex stainless steel contains: Cr 22.0–23.0%, Mo 3.0–3.5%, Ni 4.5–6.5%, N 0.14–0.20%, C ≤0.03%, Mn ≤2.00%, Si ≤1.00%, P ≤0.030%, S ≤0.020%, Fe balance.
The combination of chromium, molybdenum, and nitrogen gives S31803 its duplex microstructure and excellent corrosion resistance.
The minimum tensile strength of UNS S31803 is 620 MPa (90,000 Psi) as per ASTM A789/A790.
- Yield Strength (0.2% offset): 450 MPa min
- Elongation: 25% min
- Hardness: ≤ 290 HB
These properties make it significantly stronger than standard austenitic stainless steels like 316L.
The Pitting Resistance Equivalent Number (PREN) of S31803 is approximately 34–37, calculated using:
PREN = Cr + 3.3Mo + 16N
This places S31803 above austenitic grades like 316L (PREN ≈26) but below super duplex grades like S32750 (PREN ≥41), making it suitable for chloride-rich environments such as seawater and chemical processing.
Other Available Stock of Duplex Steel S31803 Pipes & Tubes
- Duplex Steel S31803 Capillary Tubes Trader
- Duplex Steel UNS S31803 Seamless Tube
- A789 Duplex Steel UNS S31803 Seamless Tubing
- ASTM A790 Duplex Steel S31803 Welded Pipes
- Duplex UNS S31803 Condenser Tube Distributor
- Duplex Steel UNS S31803 Heat-Exchanger Tubing
- UNS S31803 Duplex Steel Tubes Exporter
- SA790 Duplex Steel S31803 ERW Pipes
- ASME SA789 Duplex S31803 Welded Tube
- DIN 1.4462 Seamless Tubes Stockholder
- Duplex Steel UNS S31803 Tube Suppliers
- Duplex Steel UNS S31803 Tube Sizes
- Seamless Duplex S31803 Tubes Dealer
- Duplex Steel S31803 Tube Manufacturers
- Duplex Steel DIN 1.4462 Welded Tubes
- Duplex Steel UNS S31803 Tube Price List
- Duplex Steel S31803 Tube Price in India
- Duplex Steel UNS S31803 Capillary Tubing
- Duplex UNS S31803 Pipes Supplier in India
- A789 Duplex Steel S31803 ERW Tubing