Home > Welded Pipes > EFW (Electric Fusion Welded) Pipes
Inox Steel India is one of the leading manufacturers, suppliers, and global exporters of EFW (Electric Fusion Welded) Pipes in Stainless Steel, Alloy Steel, and Nickel Alloy grades, conforming to ASTM A358, A671, A672, B619, and B626 standards.
These pipes are specially engineered for high-temperature, corrosive, and high-pressure process applications, making them essential for refineries, petrochemical plants, power generation units, offshore operations, and chemical processing industries.
We export EFW Pipes to GCC, Middle East, African nations, European countries, and North & South America, supporting EPC contractors, oil & gas plants, turnkey projects, fabricators, and OEMs with reliable quality and strict documentation.
Every pipe is supplied with EN 10204 3.1 / 3.2 MTC, radiography reports, hydro test certificates, PMI results, and TPI inspections by SGS, BV, DNV, Lloyd’s, TÜV, ensuring total compliance and traceability.
EFW stands for Electric Fusion Welded, a manufacturing process used for producing large-diameter welded pipes for critical applications. Unlike ERW Pipes (Electric Resistance Welded) that use the resistance of steel edges to create heat, EFW Pipes are fused by an electric arc or electric fusion process, allowing:
EFW Pipes are preferred when the application requires:
Therefore, they are widely used in refineries, boilers, HRSG units, chemical reactors, heat exchangers, offshore lines, and fertilizer plants.
Just as seamless pipes are created through extrusion and ERW pipes from coil forming, EFW Pipes follow a more advanced fusion welding process:
1️⃣ Plate Selection & Edge Preparation
Large steel plates (SS, Alloy, Nickel) are sourced from mills and cut to the required dimensions.
The edges are prepared for welding through beveling, chamfering, and grinding.
2️⃣ Plate Rolling to Form Pipe (UOE / JCOE Method)
The plate is cold-formed into a cylindrical shape using:
This ensures perfect roundness and dimensional accuracy.
3️⃣ Electric Fusion Welding (EFW Process)
The edges are fused using:
creating a deep penetration weld suitable for high-pressure service.
4️⃣ Internal & External Weld Bead Treatment
The weld is processed using grinding or heat-based methods to ensure:
5️⃣ Heat Treatment (PWHT / Solution Annealing)
Depending on material:
6️⃣ Complete NDT & Hydrostatic Testing
Every pipe undergoes:
7️⃣ Beveling, Calibration & Final Inspection
Ends are prepared for welding (BE), then all dimensions, thickness, roundness, and length are verified.
8️⃣ Export-Ready Packing & Marking
Pipes are bundled, protected internally, capped, wrapped, and labeled with:
1. Ability to Produce Large Bore Pipes (8″ to 120″ OD)
EFW Pipes allow very large sizes needed for process transfer, waste gas lines, and reactor inlets.
2. Suitable for Critical Process Fluids
Because EFW pipes undergo 100% radiography, they are trusted for:
3. Strong Weld Integrity
Electric fusion welding creates a deep fusion joint with high reliability.
4. Supports Special Metals
EFW can be used on:
5. Excellent Corrosion & Temperature Resistance
Depending on grade, EFW pipes can operate from -196°C up to 1100°C.
🔹 Oil & Gas Refineries
Process lines, catalytic cracking, hydrocarbon transport.
🔹 Chemical & Petrochemical Plants
Corrosion-resistant flow lines, reactors, flash drums.
🔹 Power Generation & Boilers
Steam pipelines, superheater lines, HRSG units.
🔹 Fertilizer & Ammonia Plants
High-temperature pressure lines.
🔹 Offshore & Marine
Nickel alloy EFW used for seawater processing.
🔹 Desalination Plants
SS & Duplex EFW used in brine circulation.
🔹 Nuclear & Thermal Power Plants
Chrome-Moly EFW (P11/P22/P91) for boiler tubes.
EFW Pipes serve high-temperature, high-pressure, and corrosion-intensive operations where ordinary welded pipes cannot perform.
| Parameter / Property | EFW Stainless Steel Pipes (ASTM A358 / A312 Large Bore) | EFW Alloy Steel Pipes (ASTM A671 / A672) | EFW Nickel Alloy Pipes (ASTM B619 / B626) |
|---|---|---|---|
| Standard / Specification | ASTM A358, ASTM A312 (ERW/EFW for large diameter) | ASTM A671 / A672 (EFW Pressure Pipes) | ASTM B619 / B626 (Nickel Alloy EFW) |
| Material Type | Austenitic Stainless Steel | Chrome-Moly Alloy Steel | Inconel, Monel, Hastelloy, Incoloy |
| UNS Designation | S30400 / S30403 / S31600 / S31603 | K21590 (P11), K21590 (P22), K90941 (P91) | N06625 (Inconel 625), N04400 (Monel 400), N06022 (Hastelloy C22) |
| Equivalent EN / DIN / JIS | EN 1.4301 / 1.4401 | EN 1.7380 (P22), EN 1.4903 (P91) | DIN 2.4856, DIN 2.4602 |
| Chemical Composition (% Max) | (304/316) C ≤0.08, Cr 18–20/16–18, Ni 8–11/10–14, Mo 2–3 (316) | C 0.05–0.15, Cr 1.0–2.5, Mo 0.5–1.1 (varies by grade) | Ni ≥58%, Cr ≤22%, Mo ≤9%, Fe Balance |
| Tensile Strength (MPa) | ≥ 515 | 415 – 585 | 690 – 760 |
| Yield Strength (MPa) | ≥ 205 | ≥ 240 | ≥ 275 |
| Elongation (%) | ≥ 40 | ≥ 20 | ≥ 35 |
| Hardness (HB) | ≤ 192 | ≤ 200 | ≤ 230 |
| Corrosion Resistance | Excellent | Moderate–High (with PWHT) | Very High |
| Temperature Range (°C) | -196°C to +870°C | Up to 600°C | Up to 1100°C |
| Typical Applications | Chemical, petrochemical, high-temperature services | High-pressure steam, boilers, refinery lines | Corrosive fluids, offshore, seawater |
| Available Sizes (NB / OD) | 8″ – 120″ Large Bore | 8″ – 72″ | 6″ – 36″ |
| Schedules (Thickness) | SCH 10 – SCH 160 / Custom | SCH 20 – SCH 160 | SCH 40 – SCH 160 |
| End Finishes | Bevelled Ends / Plain Ends | Bevelled Ends | Bevelled Ends |
| Testing Requirements | RT, UT, Hydro, PMI, DP Test | RT, UT, PWHT Verification | RT, UT, PMI, Corrosion Testing |
| HS / HSN Code | 7306.40 | 7306.19 / 7306.29 | 7507.12 / 7507.20 |
| Equivalent ASTM / ASME | ASME SA358 / SA312 | ASME SA671 / SA672 | ASME SB619 / SB626 |
| Supply Condition | Solution Annealed, Pickled & Passivated | PWHT / Normalized | Solution Annealed |
| Certifications & Docs | MTC 3.1/3.2, CE/PED, PMI, TPI | Hydro, RT Charts, PWHT Certificates | NACE MR0175/0103 (Optional), TPI |
EFW Pipes manufactured by Inox Steel India fall into three major metallurgical families:
Stainless Steel EFW Pipes (ASTM A358 / SA358, ASTM A312 Large Bore)
Used where corrosion + temperature + cleanliness are the primary requirements.
Key Features
Typical Applications
Common Grades
Alloy Steel EFW Pipes (ASTM A671 / A672 for High-Pressure Service)
Used in power plants, boilers, HRSG units, steam lines, and refineries.
Key Features
Common Grades
Typical Applications
Nickel Alloy EFW Pipes (ASTM B619 / B626)
Used for extreme corrosion environments, seawater, offshore, and chemical reactors.
Key Features
Common Grades
Typical Applications
| NPS (Inch) | OD (mm) | Wall Thickness (mm) | Approx. Weight (kg/m) |
|---|---|---|---|
| 8″ | 219.1 | 6.0 – 14.0 | 47 – 105 |
| 10″ | 273.1 | 6.4 – 16.0 | 66 – 142 |
| 12″ | 323.9 | 6.4 – 18.0 | 82 – 202 |
| 16″ | 406.4 | 7.1 – 22.0 | 116 – 330 |
| 20″ | 508.0 | 8.0 – 25.0 | 168 – 480 |
| 24″ | 610.0 | 9.5 – 30.0 | 245 – 700 |
| 30″ | 762.0 | 10 – 32.0 | 350 – 950 |
| 36″ | 914.4 | 12 – 36.0 | 510 – 1500 |
| 48″ | 1219.2 | 14 – 40.0 | 780 – 2200 |
| Material / Grade | OD Range | INR/kg | USD/kg | Application |
|---|---|---|---|---|
| SS EFW (304/304L) | 8″–48″ | ₹ 400–₹ 600 | $ 5.0–$ 7.5 | Chemical & utility |
| SS EFW (316/316L) | 8″–48″ | ₹ 520–₹ 750 | $ 6.5–$ 9.0 | Marine, chloride service |
| Alloy Steel EFW (P11/P22) | 8″–72″ | ₹ 250–₹ 420 | $ 3.2–$ 5.6 | Steam & boiler |
| Alloy Steel EFW (P91) | 8″–48″ | ₹ 380–₹ 650 | $ 4.8–$ 8.0 | High temp/high pressure |
| Nickel Alloy EFW (Inconel/Monel/Hastelloy) | 6″–36″ | ₹ 2,800–₹ 4,500 | $ 34–$ 55 | Chemical/reactor service |
| Material | Code |
|---|---|
| Stainless Steel EFW | 7306.40 |
| Alloy Steel EFW | 7306.19 / 7306.29 |
| Nickel Alloy EFW | 7507.12 / 7507.20 |
EFW Pipes undergo more rigorous testing than ERW/seamless due to critical application requirements.
Mandatory Tests
Documentation You Receive
This mirrors your seamless pipe page’s QA structure.
GCC & Middle East:
Africa:
Europe:
Americas:
Inox Steel India supplies EFW pipes to EPC contractors + shutdown projects worldwide.
EFW Pipes are used in critical service conditions — high temperature, high pressure, corrosion-heavy, chemical-intensive environments. Selecting the wrong supplier can lead to:
This is why global EPC companies, refineries, and power plants depend on Inox Steel India for reliable high-integrity EFW Pipes.
Top Reasons to Choose Inox Steel India
| Industry | Application | Material |
|---|---|---|
| Oil & Gas Refineries | Hydrocarbon process lines, reactor connections | SS / Alloy / Nickel Alloy |
| Petrochemical Plants | Chemical transfer, high-temperature fluids | SS 316/316L / Alloy Steel |
| Power Plants | Steam lines, superheater, boiler tubes | Alloy Steel (P11/P22/P91) |
| Fertilizer & Ammonia Plants | High-pressure synthesis lines | Alloy & Nickel Alloys |
| Offshore Platforms | Seawater & corrosive fluid handling | Nickel Alloy (Inconel/Monel) |
| Nuclear Power | High-temperature & radiation-resistant lines | Alloy Steel P91 |
| Desalination Plants | Brine circulation, evaporator lines | SS / Duplex / Nickel Alloy |
| Marine & Shipbuilding | Seawater intake & discharge | SS 316L / Monel 400 |
Large OD and heavy wall EFW Pipes require enhanced protection:
✔ Premium Export Packing
✔ Export Ports
✔ Export Countries
UAE, Saudi Arabia, Oman, Qatar, Kuwait, Bahrain, Egypt, Kenya, Nigeria, South Africa, UK, Germany, Italy, USA, Canada, Mexico, Brazil, Chile.
Inox Steel India supplies high-integrity EFW Pipes with full radiography, hydro test, PMI, and TPI certification.
Whether your project requires Stainless Steel, Alloy Steel, or Nickel Alloy EFW Pipes, our engineering team ensures fast delivery and complete compliance.
52-A, Mulji Thackersi Bldg, Islampura Street, Shop No. 10, Near Alankar Cinema, Mumbai – 400 004
alloy@inoxsteelindia.in, steel@inoxsteelindia.in
+91 9930796690
Stainless Steel (304/316), Alloy Steel (P11/P22/P91), Nickel Alloys (Inconel, Monel, Hastelloy).
Yes — 100% RT is required for refineries, petrochemical plants, boilers, and power lines.
ASTM A358, ASTM A671, ASTM A672, ASTM B619, ASTM B626.
Yes — Alloy Steel EFW (A671/A672) is widely used in boiler and HRSG systems.
Yes — to GCC, Middle East, Africa, Europe, USA, Canada & South America.
Whether your project requires Stainless Steel, Alloy Steel, or Nickel Alloy EFW Pipes, our engineering team ensures fast delivery and complete compliance.
📞 Contact us today for the best price & fastest delivery.