Duplex Steel Tubes Manufacturer & Supplier in India
Kalpaturu Piping Solution is a trusted manufacturer and distributor of Duplex Steel Tube, which has a great mechanical strength and durability of corrosion. These tubes come in both the duplex and super duplex grades; hence, they can be used in harsh industrial conditions. Balanced austenitic-ferritic microstructure has excellent chloride induced stress corrosion cracking especially in aggressive marine and chemical environments.
We have Super Duplex Steel Welded Tubes that are effective in the use of the inorganic acids and which have high load carrying capacity. Nevertheless, they should not be used to a high temperature of more than 600 o C because an extended period of exposure to such temperatures can compromise toughness and corrosion resistance. Light-gauge duplex steel tubes provide comparable structural strength with nickel alloys, so the weight is reduced significantly and fewer materials are needed to make them.
Kalpaturu Piping Solution provided ERW, EFW, square, rectangular and round Duplex Steel Tubes in alternative surface finishes such as mirror and bright polished finishes. They are solution annealed and quenched following hot or cold forming in order to achieve excellent metallurgical quality. They come in different sizes that have up to 4 inches in diameter with standard lengths of 20 feet to match various project requirements. Our refined Duplex Steel Tubes also demonstrate the good performance in non-uniform corrosion by organic acids like acetic acid, which is very tedious to the tube, and this makes it durable and reliable to use in industries.
ASTM A789 Super Duplex Stainless Steel UNS S32760 Welded Tubing, Super Duplex Steel Tubes, ASME SA789 Ferritic/Austenitic Super Duplex 2507 ERW Tube Suppliers, UNS S32760 Super Duplex Tubing, Super Duplex S32750 EFW Tubes Exporters, ASTM A790 Super Duplex Steel UNS S32750 Seamless Tubes, S31803 material, UNS S31803, UNS S32205, astm a276 uns s31803 equivalent
Table of content
- Specification of Duplex Steel Tubes
- Types of Duplex Steel Tubes
- Duplex Tube Wall Thickness Chart
- Super Duplex Tubing Tolerances (As per ASTM A269 / A213)
- Typical Chemical Composition & Proof Strength of Duplex / Super Duplex Steels
- Applications of Duplex Steel Tubes
- People Ask About Nuts Manufacturer
Material Grades of Duplex Steel Tubes
Specification of Duplex Steel Tubes
Parameter | Specification |
Duplex Tube Standards | ASTM A789, ASME SA789 |
Duplex Seamless Tube Size | 3.35 mm OD to 101.6 mm OD |
Duplex Welded Tube Size | 6.35 mm OD to 152 mm OD |
SWG & BWG | 10 SWG, 12 SWG, 14 SWG, 16 SWG, 18 SWG, 20 SWG |
Duplex Tubing Wall Thickness | 0.020″ – 0.220″ (Special wall thickness available) |
Duplex Steel Tube Length | Single Random, Double Random, Standard & Cut Length |
Super Duplex Tube Finish | Polished, AP (Annealed & Pickled), BA (Bright Annealed), MF |
Duplex Tube Form | Round, Coil, Square, Rectangular, Boiler, Hydraulic, Straight, U-Bent, Hollow, LSAW Tubes |
Duplex Tube Type | Seamless, ERW, EFW, Welded, Fabricated |
Electropolished (EP) | Electropolished for Ultra-High Purity Systems |
Non-Electropolished | BA (Bright Annealed), AP (Annealed & Pickled), CFOS (Cleaned for Oxygen Service) |
I.D. Surface Finish Options | 5, 7 & 10 µin Ra |
JIS Sizes | 8A to 250A |
Tolerances | ASTM A269 & A632, JIS G 3459 |
Super Duplex Tube Ends | Plain End, Beveled End, Threaded, Orbital Welding Suitable |
Marking | Standard, Grade, OD, Thickness, Length, Heat No. (As per customer request) |
Applications | Oil Tube, Gas Tube, Fluid Tube, Boiler & Heat Exchanger |
Value Added Services | Draw & Expansion, Electro & Commercial Polishing, Annealed & Pickled, Bending, Machining |
Specialization | Duplex Capillary Tubes & Odd Sizes |
Heat Exchanger & Condenser Tubes | Available |
Duplex Hydraulic Tubing (≤ 50.8 mm OD) | Supplied in Bright Annealed Condition |
Duplex Hydraulic Tubing (> 50.8 mm OD) | Annealed & Pickled or Polished Condition |
Marking & Traceability | Etched ID within 24″ (610 mm) from one end |
Test Certificate | EN 10204 3.1 B, Govt. Approved Lab Certificate |
Inspection | Under Third Party Inspection |
Testing & Inspection | Visual, Surface Roughness, Helium Leak, SEM, AES, ESCA/XPS, Particle & Moisture Testing |
Types of Duplex Steel Tubes
Duplex U Shaped Tubing
Duplex Alloy Square Tube (Radius Corners)
Duplex Boiler Tube
Duplex Capillary Tube
Duplex Coiled Tubing
Duplex Gas Tube AR 15
Duplex Gas Tube
Duplex Heat Exchanger Tubes
Duplex Rectangle Tube
Duplex Seamless Tubing
Duplex Square Tube
Duplex Thin Wall Tube
Duplex Tubing
Duplex Welded Tubing
Duplex Tube Wall Thickness Chart
Code | Wall Thickness (Inches) |
028 | 0.028″ |
035 | 0.035″ |
039 | 0.039″ |
049 | 0.049″ |
065 | 0.065″ |
083 | 0.083″ |
109 | 0.109″ |
Super Duplex Tubing Tolerances (As per ASTM A269 / A213)
Duplex Tube Outer Diameter (OD) | Tolerance |
4 mm to 35 mm | ± 0.08 mm |
35 mm to 38 mm | ± 0.15 mm |
38 mm to 60 mm | ± 0.20 mm |
60 mm and above | ± 0.25 mm |
Typical Chemical Composition & Proof Strength of Duplex / Super Duplex Steels
Common Name | UNS No. | BS EN No. | Steel Type | C % | Cr % | Ni % | Mo % | N % | Cu % | 0.2% Proof Strength (N/mm²) |
2304 | S32304 | 1.4362 | Duplex | 0.015 | 23.0 | 4.0 | 0.055 | 0.13 | — | 400 |
2205 | S31803 | 1.4462 | Duplex | 0.015 | 22.0 | 5.5 | 3.0 | 0.14 | — | 450 |
2205 | S32205 | 1.4462 | Duplex | 0.015 | 22.5 | 5.5 | 3.3 | 0.17 | — | 450 |
255 (UR52N) | S32520 | 1.4507 | Super Duplex | 0.015 | 25.0 | 7.0 | 3–5 | 0.28 | 0.13 | 550 |
2507 | S32750 | 1.4410 | Super Duplex | 0.015 | 25.0 | 7.0 | 4.5 | 0.28 | 0.30 | 550 |
Zeron 100 | S32760 | 1.4501 | Super Duplex | 0.015 | 25.0 | 7.0 | 3.5 | 0.25 | 0.80 | 550 |
Sandvik SAF 3207 | S33207 | — | Hyper Duplex | 0.030 | 31.0 | 7.5 | 4.0 | 0.50 | 0.75 | 700 |
Duplex Tube Size Range
Type | Outer Diameter | Sizes | Length |
NB Sizes (In Stock) | 0.0035″ to 8″ | 1/8″ to 6″ | Cut to Length |
Duplex Seamless Tube (Custom) | 6.35 mm OD to 101.6 mm OD | As per requirement | Cut to Length |
Duplex Welded Tube (ERW) | 6.35 mm OD to 152 mm OD | As per requirement | Cut to Length |
Duplex Seamless Tube Surface Finish
Surface Finish | Internal Surface (ID) – Ra | External Surface (OD) – Ra | ||
µ inch | µm | µ inch | µm | |
AP (Annealed & Pickled) | Not Defined | Not Defined | 40 or Not Defined | 1.0 or Not Defined |
BA (Bright Annealed) | 40, 32, 25, 20 | 1.0, 0.8, 0.6, 0.5 | 32 | 0.8 |
MP (Mechanical Polish) | 40, 32, 25, 20 | 1.0, 0.8, 0.6, 0.5 | 32 | 0.8 |
EP (Electropolished) | 15, 10, 7, 5 | 0.38, 0.25, 0.20, 0.13 | 32 | 0.8 |
Duplex Tube Sizes Chart
Wall Thickness (Inches) | Available Outside Diameters (O.D.) |
0.010″ | 1/16″, 1/8″, 3/16″ |
0.012″ | 1/8″ |
0.016″ | 1/8″, 3/16″ |
0.020″ | 1/16″, 1/8″, 3/16″, 1/4″, 5/16″, 3/8″ |
0.028″ | 1/8″, 3/16″, 1/4″, 5/16″, 3/8″, 1/2″, 3/4″, 1″, 1 1/2″, 2″ |
0.035″ | 1/8″, 3/16″, 1/4″, 5/16″, 3/8″, 7/16″, 1/2″, 5/8″, 3/4″, 7/8″, 1″, 1 1/4″, 1 1/2″, 1 5/8″, 2″, 2 1/4″ |
0.049″ | 3/16″, 1/4″, 5/16″, 3/8″, 1/2″, 5/8″, 3/4″, 7/8″, 1″, 1 1/8″, 1 1/4″, 1 1/2″, 1 5/8″, 2″, 2 1/4″ |
0.065″ | 1/4″, 5/16″, 3/8″, 1/2″, 5/8″, 3/4″, 7/8″, 1″, 1 1/4″, 1 1/2″, 1 5/8″, 1 3/4″, 2″, 2 1/2″, 3″ |
0.083″ | 1/4″, 3/8″, 1/2″, 5/8″, 3/4″, 7/8″, 1″, 1 1/4″, 1 1/2″, 1 5/8″, 1 7/8″, 2″, 2 1/2″, 3″ |
0.095″ | 1/2″, 5/8″, 1″, 1 1/4″, 1 1/2″, 2″ |
0.109″ | 1/2″, 3/4″, 1″, 1 1/4″, 1 1/2″, 2″ |
0.120″ | 1/2″, 5/8″, 3/4″, 7/8″, 1″, 1 1/4″, 1 1/2″, 2″, 2 1/4″, 2 1/2″, 3″ |
0.125″ | 3/4″, 1″, 1 1/4″, 1 1/2″, 2″, 3″, 3 1/4″ |
0.134″ | 1″ |
0.250″ | 3″ |
0.375″ | 3 1/2″ |
Applications of Duplex Steel Tubes
- Oil & Gas pipelines and offshore platforms
- Chemical processing and petrochemical plants
- Heat exchangers, condensers, and boilers
- Desalination plants and seawater handling systems
- Hydraulic and instrumentation tubing
- Pulp and paper industry equipment
- Marine, shipbuilding, and coastal structures
- Power generation and fertilizer industries
Duplex steel tubes are preferred where high strength, corrosion resistance, and long service life are required.
Get in Touch
Looking for high-quality Duplex Steel Tubes for your industrial project? Contact Kalpataru Piping Solution today to get expert assistance, technical support, and a competitive quote tailored to your requirements.
Request a QuotePeople Ask About Nuts Manufacturer
Duplex Steel Tubes are stainless steel tubes with a mixed microstructure of austenite and ferrite, offering higher strength and better corrosion resistance than conventional stainless steels.
Super Duplex Tubes contain higher chromium, molybdenum, and nitrogen, providing superior resistance to pitting, crevice corrosion, and chloride stress corrosion cracking.
Duplex Tubes are commonly manufactured as per ASTM A789, ASTM A269, ASME SA789, and related international standards.
Yes, due to their high mechanical strength and excellent fatigue resistance, Duplex Tubes are ideal for high-pressure and high-stress environments.
Yes, Duplex Steel Tubes can be supplied in custom outer diameters, wall thicknesses, lengths, and surface finishes as per project requirements.