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Stainless Steel 420 & 431 Pipes & Tubes Supplier & Stockist in India
High-tensile structural stability, superior Rockwell hardness, and heavy mechanical wear endurance demand specialized high-carbon martensitic alloys. As a trusted Stainless Steel 420 Pipes & Tubes Supplier in India, Steel Emporium stocks high-carbon piping engineered for high-stress hydraulic lines, valve components, and wear-resistant fluid systems
To support rapid project schedules across heavy machinery and pump manufacturing sectors, we serve as a premier Stainless Steel 420 Pipes & Tubes Stockist in India. Our ready inventory of seamless and welded astm 420 stainless steel delivers elevated yield strength post-quenching, fully backed by authentic EN 10204 3.1 certification.
For severe marine environments, high-stress shafting, and hardware requiring high tensile limits alongside improved atmospheric corrosion resistance, rely on our expertise as an established supplier of Stainless Steel 431 Pipes in India. For applications demanding high thermal heat resistance or ferritic non-hardening performance, explore our complementary Stainless Steel 430 & 430Ti Pipes & Tubes inventory.
When engineering heavy-duty pump spindles, hydraulic rams, or marine valve stems, partner with a leading stockist of Stainless Steel 431 Tubes in India. We provide direct factory pricing, custom cut-to-length options, and express export clearance for all industrial piping requirements.
Jump To Section: Material Specs | Grade Selection | Size Chart | FAQs
ASTM 420 & 431 Stainless Steel Pipes & Tubes Technical Specifications
| Technical Parameter | Specification Standard & Scope |
|---|---|
| Manufacturing Standards | ASTM A268 (Seamless/Welded Ferritic & Martensitic), ASTM A312, ASME SA268 / SA312 |
| Dimensional Range | Seamless: 1/2" NB to 12" NB | ERW / Welded: 1/2" NB to 24" NB | Custom OD: 6.0 mm to 610.0 mm |
| Wall Thickness / Schedules | SCH 5S, SCH 10S, SCH 40S, SCH 80S, SCH 160, SCH XXS (Custom wall up to 30mm) |
| Form & Delivery Conditions | Round, Square, Rectangular, Hardened & Tempered (QT), Annealed, Pickled |
| End Finish & Surface Processing | Plain End (PE), Beveled End (BE), Threaded, Bright Annealed (BA), 2B Finish |
Alloy Grade Selection Guide: SS 420 vs SS 431
Choosing between SS 420 and SS 431 comes down to balancing surface hardness against corrosion resistance and yield strength. While both are heat-treatable martensitic alloys, their chemical compositions dictate vastly different performance in real-world industrial environments.
| Feature / Requirement | SS 420 (UNS S42000) | SS 431 (UNS S43100) |
|---|---|---|
| Primary Advantage | Highest surface hardness & anti-galling | High tensile/yield strength & tough impact resistance |
| Max Hardness Potential | Up to 50 HRC (Quenched & Tempered) | ~30 to 40 HRC (High Toughness Matrix) |
| Corrosion Performance | Moderate (Best in fresh water & mild media) | Superior (Resists marine salt spray & mild chemicals) |
| Nickel Content (Ni) | 0.75% max (Standard Martensitic) | 1.25% to 2.50% (Nickel-Enriched Martensitic) |
| Best Used For | Hydraulic sleeves, slurry lines, valve trim | Marine propeller shafts, subsea pumps, fasteners |
High-Carbon Grade 420 Stainless Steel Pipes
Featuring a higher carbon content (0.15% min), Grade 420 Stainless Steel Pipes respond exceptionally to quenching and tempering, reaching peak hardness up to 50 HRC. If your application involves severe sliding wear, mechanical friction, or abrasive slurry flow, UNS S42000 Pipes deliver maximum surface hardness to prevent wall erosion and galling in hydraulic sleeves and pump components.
Corrosion-Resistant AISI 431 Stainless Steel Pipe
When operating conditions require both high mechanical load capacity and resistance to aggressive media, AISI 431 Stainless Steel Pipe is the superior choice. With 1.25-2.50% nickel added to a 15-17% chromium matrix, SS 431 achieves exceptional yield strength (up to 850 MPa) and impact toughness, making it ideal for marine hardware, subsea pump shafts, and high-pressure chemical lines.
Chemical, Mechanical & Equivalent Specifications
| Element / Parameter | SS 420 (UNS S42000) | SS 431 (UNS S43100) |
|---|---|---|
| Carbon (C) | 0.15 – 0.40% max | 0.20 max |
| Chromium (Cr) | 12.00 – 14.00 | 15.00 – 17.00 |
| Nickel (Ni) | 0.75 max | 1.25 – 2.50 |
| Manganese (Mn) | 1.00 max | 1.00 max |
| Silicon (Si) | 1.00 max | 1.00 max |
| Phosphorus (P) | 0.040 max | 0.040 max |
| Sulfur (S) | 0.030 max | 0.030 max |
| Mechanical Property | Grade 420 Stainless Steel Pipes | AISI 431 Stainless Steel Pipe |
|---|---|---|
| Tensile Strength (MPa min) | 655 (Up to 1600 QT) | 850 – 1000 (QT 800) |
| Yield Strength (0.2% Proof, MPa min) | 345 (Up to 1360 QT) | 650 min |
| Elongation (% in 50mm min) | 14 | 13 |
| Hardness (Rockwell / Brinell) | 50 HRC max (Hardened) | 248 – 302 HBW (QT) |
| Standard / Agency | SS 420 | SS 431 |
|---|---|---|
| UNS Designation | UNS S42000 | UNS S43100 |
| Werkstoff Nr. | 1.4021 / 1.4028 | 1.4057 |
| EN Standard | X20Cr13 / X30Cr13 | X17CrNi16-2 |
| AFNOR | Z20 C 13 / Z30 C 13 | Z15 CN 16-02 |
SS 420 / 431 Size & Schedule Chart
| Nominal Size (NB) | Outer Diameter (mm) | SCH 10S Wall | SCH 40S Wall | SCH 80S Wall |
|---|---|---|---|---|
| 1/2" NB | 21.34 mm | 2.11 mm | 2.77 mm | 3.73 mm |
| 1" NB | 33.40 mm | 2.77 mm | 3.38 mm | 4.55 mm |
| 2" NB | 60.32 mm | 2.77 mm | 3.91 mm | 5.54 mm |
| 4" NB | 114.30 mm | 3.05 mm | 6.02 mm | 8.56 mm |
| 6" NB | 168.28 mm | 3.40 mm | 7.11 mm | 10.97 mm |
| 8" NB | 219.08 mm | 3.76 mm | 8.18 mm | 12.70 mm |
Key Industrial Applications
Heavy Hydraulic Systems & Actuators (SS 420)
Integrated into high-pressure hydraulic cylinders, piston sleeves, and wear rings requiring quenched surface hardness.
Marine Hardware & Shafting (SS 431)
Utilized for drive shafts, rudder stocks, and outboard motor components operating in brackish water environments.
Power Generation & Turbine Spindles (SS 420 / 431)
Applied in steam control valve trim, governor stems, and pump sleeves operating under continuous torsional stress.
Chemical Process Control Valves (SS 431)
Specified for valve plugs, seats, and internal fittings exposed to mild acidic wash solutions and high torque loads.
Quality Control, MTC Documentation & Testing Standards
Every pipe shipment undergoes stringent quality clearance protocols before dispatch to guarantee dimensional accuracy and structural integrity.
| Certification / Standard | Compliance & Testing Scope |
|---|---|
| ISO 9001:2015 & Pressure Compliance | Certified QMS with PED 2014/68/EU and AD 2000 Merkblatt approvals. |
| EN 10204 3.1 & 3.2 MTC | Official test reports covering heat numbers, chemistry, and factory origin tracking. |
| PMI & Lab Verification | 100% XRF spectro testing and NABL-accredited laboratory inspections. |
| Mechanical & Weld NDT | Hydrostatic, ultrasonic, and flaring tests guarantee 100% seam integrity. |
| TPI & Corporate Address | Inspection-ready for SGS, TUV, Bureau Veritas, or Lloyds. |
| Verified Corporate Address | Registered Head Office & Operations: 102, Durga Devi Street, Mumbai-400004, Maharashtra, India |
Frequently Asked Questions
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