Home > Square Bars > Duplex & Super Duplex Round Bars
Inox Steel India is a trusted manufacturer, supplier, and exporter of Duplex & Super Duplex Stainless Steel Round Bars in grades UNS S31803 / S32205 (Duplex 2205) and UNS S32750 (Super Duplex 2507), supplied in compliance with ASTM A479 / ASTM A276 standards.
Our duplex and super duplex round bars are widely used in offshore, marine, oil & gas, desalination, chemical processing, and high-chloride environments, where strength and corrosion resistance must perform together.
With consistent stock availability in hot rolled, forged, bright drawn, and peeled & polished conditions, Inox Steel India supports critical engineering projects and export requirements across India, GCC, Middle East, Africa, Europe, and the Americas.
What Are Duplex & Super Duplex Round Bars & How Are They Manufactured?
Duplex and super duplex round bars are solid stainless steel bars engineered with a dual-phase microstructure (austenite + ferrite). This structure provides a unique combination of high mechanical strength, excellent resistance to pitting and crevice corrosion, and superior stress corrosion cracking resistance.
Compared to conventional austenitic stainless steels, duplex grades offer almost double the yield strength, allowing lighter and more efficient component design.
Manufacturing Process Overview
This controlled process ensures duplex and super duplex round bars capable of long-term service in aggressive and chloride-rich environments.
Key Advantages of Duplex & Super Duplex Round Bars from Inox Steel India
These advantages make duplex and super duplex round bars ideal for critical rotating parts, shafts, valves, and pressure-loaded components.
MASTER TECHNICAL DATA SHEET:
Duplex & Super Duplex Round Bars
| Parameter | Duplex 2205 (UNS S31803 / S32205) | Super Duplex 2507 (UNS S32750) |
|---|---|---|
| Product Form | Solid Round Bar | Solid Round Bar |
| Material Category | Duplex Stainless Steel (22% Cr) | Super Duplex Stainless Steel (25% Cr) |
| Standard | ASTM A479 / ASTM A276 | ASTM A479 / ASTM A276 |
| EN / DIN Equivalent | EN 1.4462 | EN 1.4410 |
| Manufacturing Process | Hot Rolled / Forged / Bright Drawn | Hot Rolled / Forged / Bright Drawn |
| Diameter Range (mm) | 6 – 350 mm | 6 – 300 mm |
| Standard Sizes (mm) | 8, 10, 12, 16, 20, 25, 32, 40, 50, 65, 80, 100 | Same as Duplex |
| Length | Random / Fixed / Cut-to-Length | Random / Fixed / Cut-to-Length |
| Surface Finish | Black / Bright / Peeled & Polished | Black / Bright / Peeled & Polished |
| Density (g/cm³) | ~7.8 | ~7.8 |
| Chemical Composition (Typical %) | Cr 21–23, Ni 4.5–6.5, Mo 2.5–3.5, N 0.14–0.20, C ≤0.03 | Cr 24–26, Ni 6–8, Mo 3–5, N 0.24–0.32, C ≤0.03 |
| Tensile Strength (MPa) | ≥ 620 | ≥ 800 |
| Yield Strength (MPa) | ≥ 450 | ≥ 550 |
| Elongation (%) | ≥ 25 | ≥ 25 |
| Hardness | ≤ 290 HB | ≤ 310 HB |
| Corrosion Resistance | Excellent in chloride & marine environments | Superior pitting/crevice resistance for high-chloride service |
| Temperature Service (Guideline) | Up to ~250–300°C | Up to ~250–300°C (avoid prolonged 300–350°C exposure) |
| Heat Treatment | Solution Annealed | Solution Annealed |
| Typical Applications | Shafts, valves, pump parts, marine fittings, chemical components | Offshore, subsea, desalination, high-chloride plants, chemical pumps |
| Testing | Chemical, Mechanical, UT, PMI, Ferrite Test | Chemical, Mechanical, UT, PMI, Ferrite Test, ASTM G48 (pitting) when required |
| Certification | EN 10204 3.1 / 3.2, PED (if required) | EN 10204 3.1 / 3.2, PED, NACE MR0175/MR0103 (if required) |
| HSN / HS Code | 7222 (stainless steel bars/rods) | 7222 (stainless steel bars/rods) |
| Export Suitability | Domestic & Export | Export (critical service) |
Grades & Standards Available
Inox Steel India supplies duplex stainless steel round bars in the following grades:
Applicable Standards:
ASTM A479 / ASTM A276
EN equivalents available on request
Key Factors to Consider When Selecting Duplex & Super Duplex Round Bars
When selecting duplex or super duplex round bars, the following parameters are critical:
India:
Strong demand from chemical plants, desalination units, offshore fabricators, and pump manufacturers in Mumbai, Chennai, Gujarat, and coastal regions.
GCC & Middle East:
Extensively used in offshore platforms, seawater piping, valves, and subsea components.
Europe & Americas:
Preferred for high-integrity marine, energy, and chemical processing equipment requiring ASTM and PED compliance.
Inox Steel India supports these markets with ready stock, export documentation, and consistent supply schedules.
Applications of Duplex & Super Duplex Round Bars
Duplex and super duplex round bars supplied by Inox Steel India are engineered for applications requiring a combination of high mechanical strength and exceptional corrosion resistance, particularly in chloride-rich and aggressive environments.
Application-Wise Usage
| Industry / Sector | Typical Applications | Preferred Grades |
|---|---|---|
| Oil & Gas | Shafts, valve components, connectors | Duplex 2205 |
| Offshore & Marine | Propeller shafts, fasteners, risers | Super Duplex 2507 |
| Desalination Plants | Pump shafts, seawater handling parts | Super Duplex 2507 |
| Chemical Processing | Reactor internals, agitator shafts | Duplex 2205 |
| Power & Energy | High-strength mechanical components | Duplex 2205 |
| Pulp & Paper | Digesters, pressure-loaded parts | Duplex 2205 |
These applications demand high yield strength, resistance to stress corrosion cracking, and long service life, which duplex and super duplex steels consistently deliver.
Duplex & Super Duplex Round Bar Size Range & Standard Dimensions
Inox Steel India supplies duplex and super duplex round bars in a comprehensive size range suitable for machining, forging, and structural applications.
Standard Diameter Range (mm)
6 mm, 8 mm, 10 mm, 12 mm, 16 mm, 20 mm, 25 mm, 32 mm, 40 mm, 50 mm, 65 mm, 80 mm, 100 mm and above up to 350 mm
Length Options
Finish Options
Bright and peeled bars are preferred for precision machining and rotating components.
Duplex & Super Duplex Round Bar Weight Calculation
The standard formula used for estimating round bar weight:
Weight (kg/m) = (D² × 0.006165)
Where D = Diameter in mm
This calculation is commonly used for material planning, logistics estimation, and cost evaluation, including duplex round bar weight calculators used by buyers.
Duplex & Super Duplex Round Bar Price – Indicative Range
Prices vary based on grade, diameter, finish, and certification requirements. Below is an indicative price range for reference.
| Grade | Approx. Price INR/kg | Typical Use |
|---|---|---|
| Duplex 2205 (S31803 / S32205) | ₹ 380 – ₹ 580 | Marine & chemical service |
| Super Duplex 2507 (S32750) | ₹ 620 – ₹ 950 | Offshore & high-chloride environments |
Prices are indicative and subject to change based on alloy surcharge, certification (NACE / PED), and size.
HSN / HS Code for Duplex & Super Duplex Round Bars
Applicable for stainless steel bars and rods under Indian and international trade classification.
Duplex round bar prices generally range from ₹380 – ₹580 per kg, depending on size and finish. They are widely used in offshore platforms, desalination plants, and high-chloride chemical environments. The HSN code is 7222. Yes, controlled heat input and suitable filler metals are recommended to maintain phase balance. Yes, we supply peeled & polished duplex and super duplex round bars for precision applications. What is the typical price of duplex round bars in India?
Where are super duplex round bars commonly used?
What is the HSN code for duplex and super duplex round bars?
Do duplex round bars require special welding procedures?
Do you supply peeled and polished duplex round bars?
Why Choose Inox Steel India for Duplex & Super Duplex Round Bars
Inox Steel India is a dependable duplex and super duplex round bar manufacturer and supplier in India, supplying high-performance stainless steel bars for critical marine, offshore, and chemical processing applications. With consistent availability of Duplex 2205 (UNS S31803 / S32205) and Super Duplex 2507 (UNS S32750) round bars, we support projects where corrosion resistance and mechanical strength are equally critical.
Our Core Strengths
Our focus is on material reliability, correct grade selection, and long-term service performance in aggressive environments.
Industries We Serve
| Industry | Application |
|---|---|
| Offshore & Marine | Shafts, fasteners, risers |
| Oil & Gas | Valves, connectors, pressure parts |
| Desalination | Pump shafts, seawater systems |
| Chemical Processing | Reactor internals, agitators |
| Power & Energy | High-strength mechanical components |
| Pulp & Paper | Digesters, pressure-loaded parts |
Each industry is supported with technical guidance, inspection support, and dependable supply timelines.
Packaging & Export Readiness
All duplex and super duplex round bars are packed to ensure safe handling and corrosion protection:
Export Destinations:
UAE, Saudi Arabia, Oman, Qatar, Nigeria, South Africa, Germany, Italy, USA, and other global markets.
Dispatch is handled through JNPT (Mumbai), Mundra, and Hazira ports.
Duplex & Super Duplex Round Bar Supplier Near Alankar Cinema, Mumbai
If you are searching for a duplex or super duplex round bar supplier near Alankar Cinema, Mumbai, Inox Steel India offers immediate availability, certified material, and nationwide as well as export delivery support.