ERW (Electric Resistance Welded)
/glossary/erwPipe formed by rolling steel strip and welding the seam using electric resistance heat.
ERW pipe is steel strip formed into a cylinder and joined along one longitudinal seam by resistance heat and pressure. Kanpur fabricators in Fazalganj and Chakeri buy it as IS 1239 class tube or as ASTM A53 Type E. The A53/A53M-24 abstract covers Type E from NPS 1/8 to NPS 26. An ERW proforma from Bartan Bazar adds GST 18% on top of the dated ₹/kg band.
In detail
Electric Resistance Welded (ERW) pipe is made by forming steel strip into a cylinder and joining the longitudinal seam with resistance heating and pressure. Product range, heat treatment, examination, dimensions, grade, and permitted service come from the product standard and mill capability. ERW construction alone does not set a pressure rating. Select it through the governing code, the design calculation, the approved material line, and the inspection plan.
What ERW is, and what it is not
ERW is a manufacturing route. The mill forms coil or strip into a round and forges the two edges together with electric-resistance heat and pressure. No filler metal is added. The weld runs straight along the length. High-frequency current is the usual heat source on modern mills; the purchase order still names the product standard, not the frequency.
ASTM A53/A53M-24 Type E is the American call-out for electric-resistance-welded pipe, Grades A and B, furnished nonexpanded or cold expanded at the manufacturer's option. The store abstract covers NPS 1/8 to NPS 26 and intends the pipe for mechanical and pressure applications and for ordinary steam, water, gas, and air lines.
On Indian jobs the common product standards are IS 1239 Part 1 for 15-150 mm NB class tube, IS 3589 for larger water pipe when the mill can ERW that OD, and IS 4923 for structural hollow sections. Those books are not interchangeable. The word ERW does not pick one of them.
ERW is not seamless pipe. It is not HSAW spiral SAW. It is not LSAW plate pipe. A scarfed weld bead does not make a hydraulic seal bore. Commodity MS from the Kanpur yard does not become A106 by adding an MTC.
Who should specify ERW, and who should stay seamless or SAW
Specify ERW when the approved drawing names a welded product standard: IS 1239 for utility water and gas, A53 Type E for a general-purpose black or GI line, IS 3589 ERW at the lower end of that OD range, or IS 4923 for a structural hollow. Fazalganj shops use it for frames, racks, and ordinary plant air.
Stay on seamless when the drawing names A106, SA192, SA210, or SA213. Stay on HSAW or LSAW when the OD and wall sit in the large-diameter SAW window on the LSAW and HSAW product page. A spiral or longitudinal SAW mill is a different enquiry.
Do not treat ERW as a cheaper seamless. The seam is a designed feature with its own tests. A53 Type E requires hydrostatic testing without leakage through the weld or the body, plus tension, bend, flattening, and nondestructive electric tests as the abstract lists.
Do not pick Light-class ERW for a wet riser without checking the approved fire-NOC drawing; the fire hydrant spec shows a cited CPWD reference naming Heavy (C-class) within its own scope. Do not put ERW on a sour oilfield line unless the approved NACE route and the product standard both allow that exact welded construction.
ERW versus seamless versus HSAW
Pick the process from the drawing, then compare rupees. The table is a process map for a Kanpur buyer, not a pressure ranking.
| Process | Starting stock | Seam | Typical standard on this site | Usual Kanpur duty |
|---|---|---|---|---|
| ERW | Steel strip or coil | One longitudinal resistance weld | IS 1239 Part 1; A53 Type E | Water, GI, fabrication, plant air |
| Seamless | Solid billet | None | A106; SA192; SA210; SA213 | Steam pipe, boiler tube, hydraulic barrel mother tube, where the governing specification and drawing name seamless |
| HSAW | Coil, helical form | Helical submerged-arc weld | IS 3589; API 5L | Trunk water, piling, large OD |
| LSAW | Plate, UOE or JCOE | Straight submerged-arc weld | API 5L; IS 3589 | Transmission and heavy wall |
A53 Type F is furnace-butt-welded, not ERW. Type S is seamless. An RFQ that says only A53 Grade B can return Type E when the isometric wanted Type S.
The seamless row lists the usual Kanpur duty, not an exclusive rule; the governing specification and drawing pick the product form for a given steam, boiler, or hydraulic-barrel line.
How to specify ERW on an RFQ
Name the standard before the process. ERW 80 NB is not a complete line. Send the pack on the RFQ so the mill or the yard prices one product.
- Standard: IS 1239 Part 1, ASTM A53 Type E, IS 3589 ERW, or IS 4923. Write the edition the drawing uses.
- Size: NB and class for IS 1239; NPS and schedule for A53; OD and wall for IS 3589.
- Grade: Grade A or B on A53; Fe 330 / 410 / 450 on IS 3589. IS 1239 lines carry NB and class, not a YST grade field; YST 210 / 240 / 310 are IS 1161 structural-tube grades.
- Length: 6 m commercial on the MS ERW list; state DRL or cut-to-length with a tolerance.
- Ends: plain, threaded and coupled, or bevel when the joint detail is a butt weld.
- Finish: black, or hot-dip zinc. The amended IS 4736 minimum average zinc mass is 360 g/m² where that coating standard applies.
- Tests: hydro or eddy-current as the ordered edition requires. A53 Type E adds the abstract's nondestructive electric test on each length, alongside hydrostatic, tension, bend, and flattening tests.
- Documents: EN 10204 3.1, heat on the stencil, BIS licence on an IS line. TPI if the tender names the agency.
- Delivery: quantity in metres or MT, ex-warehouse Kanpur or the named PIN. GST 18% extra on the invoiced steel.
Worked mass for 90 lengths of 80 NB Heavy ERW
The site formula is W = (OD − t) × t × 0.02466 kg/m. The class chart and weight table give 80 NB Heavy as OD 88.9 mm and wall 4.8 mm. W = (88.9 − 4.8) × 4.8 × 0.02466 = 84.1 × 4.8 × 0.02466 = 9.95 kg/m. One 6 m length is 59.7 kg.
Ninety lengths are 90 × 59.7 = 5,373 kg, or 5.373 MT. The MS ERW price list band for 80 NB Heavy is ₹55-63 per kg ex-warehouse Kanpur as of 24 May 2026. The steel line is 5,373 × 55 = ₹2,95,515 to 5,373 × 63 = ₹3,38,499 before tax and freight.
The same 90 lengths in Medium class weigh 90 × 50.2 = 4,518 kg. A Medium offer looks cheaper per metre because the wall is 4.0 mm, not because ERW became a different process.
Common mistakes when buying ERW
In practice, buyers write ERW pipe and accept whichever standard the stockist has on the rack. The inspector then finds A53 Type E against an IS 1239 BOQ, or the reverse. OD overlap is not approval.
A second failure offers ERW against an A106 steam line. A53 Type E and A106 Grade B share a grade letter. Only Type S even sits in the seamless family, and it is still not A106 high-temperature pipe.
A third failure hides the seam on a hydraulic barrel RFQ. Dada Nagar cylinder shops start from cold-drawn seamless tube. An ID bead is a seal reject.
A fourth failure skips the nondestructive electric test on an A53 Type E line that the abstract requires on the pipe. Hydrotest alone is not the full Type E pack.
A fifth failure loads Light, Medium, and Heavy in one bundle without tags. The store then issues 3.2 mm wall against a 4.8 mm isometric.
Standards that govern an ERW purchase
IS 1239 Part 1:2004 is the Indian class-tube book for 15-150 mm NB. The BIS product manual PM/1239 (Part 1)/4 states eddy-current or hydrostatic testing to 5 MPa on each tube. IS 3589:2001 covers 168.3 mm to 2540 mm OD and groups manufacture as ERW or SAW; LSAW and spiral SAW (HSAW) are SAW-route variants sold in that OD range rather than separate categories the manual enumerates.
ASTM A53/A53M-24 Type E is the ERW type. The abstract requires tension, bend, flattening, hydrostatic testing without leakage through the weld seam or the pipe body, and a nondestructive electric test. Type F is not ERW. Type S is not ERW.
IS 4923 covers hollow steel sections for structural use. A square or rectangular ERW section is not an IS 1239 round tube. Write the structural standard on that line.
A schedule number on an A53 line does not fix pressure. Size, wall, allowable stress, and the design code do. See the pipe schedule chart for B36.10M walls used on this site.
Buying ERW pipe from Kanpur
Fazalganj and Chakeri fabrication shops collect black ERW from the Bartan Bazar / Basanti Nagar (208014) yard for frames and plant utilities. Jajmau tanneries and Panki process units buy the same process on water and air lines, then split GI and black on the packing list.
See ERW pipes and tubes, the ERW process hub, MS ERW pipe in Kanpur, and steel pipes in Kanpur. City pages for Lucknow, Agra, and Patna use that same origin.
The MS ERW list covers 15-150 NB at ₹47-70 per kg as of 24 May 2026. Seamless A106/A53 bands on the other list are a different product. Do not budget a welded 80 NB Heavy line from the seamless 3 inch Sch 40 column.
Daily trucks from this yard serve Uttar Pradesh, Bihar, Madhya Pradesh, Delhi NCR, and Uttarakhand, as the FAQ already states. Name the PIN so the carrier plan matches the bundle length.
Weld identity and receipt checks on ERW
The longitudinal seam should be visible or traceable on the stencil. A mill that scarfs the bead still owes the heat number, the standard, and the class or schedule on the body.
Match stencil, bundle tag, heat, and MTC before release. On an IS 1239 line, read NB and class. On an A53 line, read type, grade, and schedule. A Type E stencil does not support a Type S PO.
Look at end condition. A crushed plain end on a weld-prep job costs a cut. A crushed thread on a T&C job costs a coupling. Ask the loader to keep protectors on until the site.
A53 Type E mechanicals used on this site
When the drawing names A53 Type E, copy Grade A or Grade B from the piping class. This site's A53 page lists Grade A at 205 MPa yield min and 330 MPa tensile min, and Grade B at 240 MPa yield min and 415 MPa tensile min. Those figures are not IS 1239 YST numbers.
| Grade | Yield min (MPa) | Tensile min (MPa) | Typical Kanpur use |
|---|---|---|---|
| A53 Grade A | 205 | 330 | Close coiling or cold bend when the abstract prefers Grade A |
| A53 Grade B | 240 | 415 | General Type E utility and fire-header work |
| IS 1239 (class tube) | no grade field; Light / Medium / Heavy class | 330-430 on the IS 1239 page | Indian class tube, not an A53 grade |
Grade B on A53 is not Grade B on A106 and not Grade B on API 5L. Write the full designation. The abstract prefers Grade A when close coiling or cold bending is required; it does not forbid cold bending Grade B.
Lead time for stocked ERW versus a mill roll
Stocked IS 1239 sizes follow the 3-7 day band on the lead-time entry. A named mill, a non-standard length, or a TPI hold follows the 14-21 day mill-direct band for standard grades.
Cut-to-length is a yard service this site already offers. State the finished length and the end finish so the operator does not ship random 6 m against a 5.8 m BOQ.
A mixed Light and Heavy truck is possible when tags stay on and the packing list splits the classes. The price-list FAQ already says the quotation should confirm consolidation.
Where you'll meet this in procurement
You will meet ERW (Electric Resistance Welded) when choosing process route and product family. Match ERW (Electric Resistance Welded) to pressure, temperature, corrosion duty, and standard (IS, ASTM, ASME, or API) so the mill route and documentation line up with the application.
Related terms
Related resources
Key points
- ERW is a longitudinal resistance-welded route from steel strip; it is not seamless, HSAW, or LSAW.
- ASTM A53/A53M-24 Type E covers electric-resistance-welded pipe, NPS 1/8 to NPS 26, Grades A and B.
- IS 1239 Part 1 is the usual Indian class-tube book for 15-150 mm NB ERW; IS 3589 permits ERW at larger OD.
- 80 NB Heavy is 88.9 mm OD by 4.8 mm wall, 9.95 kg/m and 59.7 kg per 6 m on the site weight table.
- ERW construction alone is not a pressure rating; the product standard, wall, and design code set the duty.
Frequently asked questions
Sources
- ASTM A53/A53M-24. Standard Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded and Seamless. Type E electric-resistance-welded, NPS 1/8 to NPS 26 (ASTM International)
- PM/1239 (Part 1)/4 Feb 2022. Product Manual for IS 1239 (Part 1):2004. NB 15-150 mm, Light/Medium/Heavy, hydro or eddy-current 5 MPa (Bureau of Indian Standards)
- PM/IS 3589:2001. Product Manual for Steel Pipes for Water and Sewage (168.3 to 2540 mm OD); manufacture grouped as ERW or SAW (Bureau of Indian Standards)
- CPWD General Specifications for Electrical Works, Part V (2020). Fire-fighting works — mild steel Heavy (C-class) pipe to IS 1239 up to 150 mm, within that specification's scope, as cited on the site fire hydrant spec (Central Public Works Department (CPWD))