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INOX STEEL INDIA is a global manufacturer and supplier of EFW (Electric Fusion Welded) Tubes in Stainless Steel, Duplex, Super Duplex, and Nickel Alloys, engineered specifically for heat-transfer applications, including heat exchangers, condensers, boilers, coolers, reheaters, petrochemical heaters, and pressure processing systems.
Our EFW Tubes are produced in accordance with ASTM A249, ASTM A269, ASTM A312, ASTM A358, ASTM B515/B516/B626, and EN 10217-7, ensuring excellent weld integrity, corrosion resistance, and temperature stability. With advanced fusion welding systems, post-weld heat treatment, and 100% radiography (RT) evaluation, every EFW tube delivers consistent performance under thermal cycling, vibration, and corrosive operating environments.
Used extensively by EPC contractors, fertilizer plants, petrochemical units, thermal power plants, desalination units, and offshore industries, INOX STEEL INDIA is recognized for supplying fully certified, high-accuracy, heat-transfer-grade EFW Tubes to 60+ countries.
An EFW Tube is a welded tube manufactured using high-voltage electric arc fusion, where the edges of the plate or strip are melted and fused together, creating a full-penetration weld. Unlike ERW (Electric Resistance Welded), EFW uses a fusion arc, enabling:
EFW tubes are the preferred choice where welded integrity must match or exceed base metal performance.
This process ensures zero weld defects, low thermal stress, and excellent corrosion performance — critical for heat-transfer equipment.
EFW Tubes are manufactured in:
Standards include:
Stainless Steel & Nickel Alloy Welded Tubes for Heat-Transfer Service
| Section | Parameter | Technical Specification |
|---|---|---|
| General | Product | EFW (Electric Fusion Welded) Tubes / Pipes |
| Manufacturing Method | Electric Fusion Welding (High Voltage Arc Fusion) | |
| Application Focus | Heat Exchangers • Condensers • Boilers • Pressure Pipelines • Chemical Processing | |
| Weld Type | Longitudinal Fusion Weld (Arc Fusion) – No filler metal OR with filler based on standard | |
| Shapes Available | Round Tubes (Primary) | |
| Length | 3m–12m (Custom up to 15m) | |
| Surface Finish | Annealed • Pickled • Bright Annealed • Polished | |
| Applicable Standards | ASTM A249 • ASTM A312 • ASTM A358 • ASTM A269 • ASTM B515/B516/B626 • EN 10217-7 | |
| Material Grades | Stainless Steel | 304/304L • 316/316L • 310S • 321 • 347 («Heat-Transfer Grades») |
| Duplex / Super Duplex | S31803 • S32205 • S32750 • S32760 (EFW Equivalent) | |
| Nickel Alloys | Inconel 600/625 • Incoloy 800/825 • Monel 400 • Hastelloy C22/C276 | |
| Dimensional Range | OD | 6 mm – 508 mm |
| Thickness | 0.8 mm – 12.70 mm | |
| Length | 3m–12m | |
| Tolerance | OD ±0.5% • WT ±10% • Straightness 1.5 mm/m | |
| Mechanical Properties – Stainless Steel EFW | 304/304L | YS 205 MPa • TS 515 MPa • EL 40% |
| 316/316L | YS 205 MPa • TS 515 MPa • EL 40% | |
| 321/347 | YS 205 MPa • TS 515 MPa • EL 40% | |
| 310S | YS 210 MPa • TS 520 MPa • EL 40% | |
| Mechanical Properties – Nickel Alloy EFW | Inconel 600 | YS 240 MPa • TS 655 MPa • EL 40% |
| Inconel 625 | YS 445 MPa • TS 965 MPa • EL 30% | |
| Monel 400 | YS 170 MPa • TS 480 MPa • EL 35% | |
| Incoloy 800H/HT | YS 205 MPa • TS 550 MPa • EL 30% | |
| Hastelloy C22/C276 | YS 283–310 MPa • TS 690–760 MPa • EL 40% | |
| Chemical Composition – SS (Typical) | 304/304L | Cr 18–20 • Ni 8–12 • C ≤0.03–0.08 |
| 316/316L | Cr 16–18 • Ni 10–14 • Mo 2–3 • C ≤0.03–0.08 | |
| 321/347 | Cr 17–19 • Ni 9–13 • Stabilized (Ti/Nb) | |
| 310S | Cr 24–26 • Ni 19–22 | |
| Chemical Composition – Nickel Alloys | Inconel 600 | Ni 72 min • Cr 14–17 • Fe 6–10 |
| Inconel 625 | Ni 58 min • Cr 20–23 • Mo 8–10 • Nb 3.1–4.1 | |
| Hastelloy C22 | Ni balance • Cr 20–22 • Mo 12–14 | |
| Hastelloy C276 | Ni balance • Cr 15–17 • Mo 15–17 | |
| Incoloy 825 | Ni 38–46 • Cr 19–23 • Mo 2.5–3.5 | |
| Weld Characteristics | Weld Form | Full-penetration fusion weld, uniform bead structure |
| Weld Quality | Equal or superior to base metal (post-weld heat treatment as required) | |
| Weld NDT | RT (Radiography) • UT • Eddy Current • Visual • PT | |
| Heat Treatment | Bright Annealed • Solution Annealed | |
| Testing & QA | Mandatory | Hydrostatic • Radiographic (RT) • Eddy Current • UT • Visual & Dimensional |
| Optional | PMI • Intergranular Corrosion (IGC) • Pitting Test (ASTM G48 for Duplex) • Microstructure Analysis | |
| Certification | EN 10204 3.1 / 3.2 • ISO 9001 • PED • NACE (For Duplex/Nickel) | |
| Applications | Heat-Transfer Use | Heat Exchangers • Condensers • Boilers • Heater Tubes • Evaporators |
| Process Industries | Chemical • Petrochemical • Fertilizer • Refinery | |
| Corrosive Environments | Seawater • High-chloride • Acidic / alkaline media | |
| High-Temp Service | 310S • Inconel 600/625 • Incoloy 800H/HT | |
| End Finishes | End Types | Plain End • Bevelled End |
| Surface Protection | Pickled • Passivated • Polished | |
| HSN Code | Stainless Steel EFW | 7306.40.00 |
| Nickel Alloy EFW | 7306.90.90 |
Choosing the right EFW tube depends on the application, environment, and compliance standards.
Here are the six crucial parameters to evaluate before selection:
Temperature Resistance:
Corrosion Resistance:
Select Nickel Alloys for high chloride or Duplex for pitting/crevice resistance.
Pressure & Stress Conditions:
EFW (A358) is suitable for heavy-wall pressure service with uniform properties.
Heat-Transfer Efficiency:
Smooth finishes like bright annealed help maintain efficient thermal conductivity.
Compliance Requirements:
Ensure ASTM, EN, PED, NACE with radiography, PMI, and IGC testing.
End Use Compatibility:
Match thickness, OD, material grade, and finish to heat exchanger design.
India:
Middle East (GCC):
Africa:
Europe & Americas:
INOX STEEL INDIA maintains ready stock and export logistics with port dispatch from JNPT (Mumbai), Mundra, and Hazira — ensuring timely delivery.
EFW Tubes from INOX STEEL INDIA are specifically engineered for applications requiring deep weld penetration, heat-transfer performance, and temperature stability.
Stainless Steel EFW Tubes (ASTM A249 / A269 / A312 / A358)
Duplex & Nickel Alloy EFW Tubes (ASTM A928 / B515 / B516)
| OD (mm) | OD (Inch) | Thickness (mm) | Length | Notes |
| 6 – 38 mm | ¼″ – 1½″ | 0.8 – 3.0 | 3m – 12m | Heat exchanger tubes |
| 38 – 114 mm | 1½″ – 4½″ | 1.0 – 6.0 | 3m – 12m | Condenser/heater tubes |
| 114 – 219 mm | 4½″ – 8″ | 2.0 – 10.0 | 6m – 12m | Pressure service |
| 219 – 508 mm | 8″ – 20″ | 3.0 – 12.7 | 6m – 12m | Large OD EFW piping |
Custom OD & WT combinations available based on A358 & B515/B516.
| Material / Grade | Size Range (OD) | Avg. Price INR / kg | Approx. USD / kg | Typical Use |
| SS 304 / 304L EFW | 6 – 219 mm | ₹ 360 – ₹ 420 | $ 4.30 – $ 5.00 | Condensers / heat exchangers |
| SS 316 / 316L EFW | 6 – 219 mm | ₹ 420 – ₹ 520 | $ 5.00 – $ 6.25 | Marine & chemical service |
| SS 321 / 347 EFW | 12 – 219 mm | ₹ 450 – ₹ 600 | $ 5.45 – $ 7.20 | High-temp heaters |
| SS 310S EFW | 25 – 219 mm | ₹ 650 – ₹ 860 | $ 8.00 – $ 10.20 | High-temperature furnaces |
| Duplex / Super Duplex EFW | 12 – 219 mm | ₹ 680 – ₹ 950 | $ 8.20 – $ 11.40 | Desalination / offshore |
| Nickel Alloy EFW | 6 – 219 mm | ₹ 2,500 – ₹ 3,800 | $ 28 – $ 42 | Extreme corrosion & temperature |
Prices depend on origin, thickness, finish, NDT level & project quantity.
INOX STEEL INDIA conducts full weld integrity testing, ensuring suitability for heat-transfer & pressure duties.
Mandatory Tests:
Optional Tests: PMI, IGC test (ASTM A262), Pitting Resistance (ASTM G48), Microstructure, Surface roughness. All dispatched with EN 10204 3.1 / 3.2, ISO 9001, PED 2014/68/EU.
Key Advantages Our Clients Rely On:
When buyers search for “EFW pipe supplier near me” or “Stainless steel EFW tube dealers in Mumbai”, INOX STEEL INDIA is the preferred supplier due to central Mumbai location, immediate stock availability, on-site inspection, and same-day dispatch in the Mumbai/Pune region.
| Industry | Key Applications | Preferred Grades |
| Petrochemical & Refinery | Heaters · Boilers · Reactors | 316L · 321 · 347 · Inconel 600/625 |
| Chemical Processing | Heat exchangers · Acid lines | 316L · Duplex · Hastelloy |
| Desalination & Marine | Seawater exchangers · Cooling coils | Duplex · Super Duplex · 316L |
| Thermal & Power Plants | Superheaters · Reheaters | 321 · 347 · 310S |
| Fertilizer Industry | Ammonia heaters · Urea equipment | 316L · Incoloy 800H/HT |
| Offshore & Subsea | Corrosive heat-transfer units | Duplex · Hastelloy · Inconel |
Every EFW tube is export-ready, packed as per international shipping requirements:
Our technical team provides guidance from material selection to dimensional optimization. Whether you require 316L EFW tubes for heat exchangers, 310S for high-temperature heaters, or Nickel Alloy EFW for extreme corrosion, we are ready to assist.
52-A, Mulji Thackersi Bldg, Islampura Street, Shop No. 10, Near Alankar Cinema, Mumbai – 400 004
alloy@inoxsteelindia.in, steel@inoxsteelindia.in
+91 9930796690
ERW uses high-frequency resistance heat, while EFW uses arc fusion. Seamless is best for high-pressure internal systems. Yes — EFW is widely used in heat exchangers, boilers, condensers, evaporators, especially in corrosive & high-temperature service. Yes — Inconel, Monel, Hastelloy, Incoloy in A358/B515/B516/B626 standards. Absolutely — 100% RT is provided for all EFW welds. Refinery • Petrochemical • Chemical • Power • Fertilizer • Marine • Offshore. How is an EFW pipe different from an ERW pipe?
EFW allows:
✔ deeper penetration
✔ thicker material welding
✔ superior corrosion resistance in weld zone Is EFW better than seamless?
EFW is superior for heat-transfer, high-temperature, and corrosive applications where welding integrity is crucial. Are EFW tubes suitable for heat exchangers?
Do you supply alloy and nickel EFW pipes?
Can I get EFW tubes with radiographic testing (RT)?
Which industries use EFW tubes the most?
At INOX STEEL INDIA, our EFW Tubes deliver global-standard weld integrity, corrosion resistance, temperature stability, and thermal performance for the most demanding industrial applications.