What is ERW (MS) pipe?
ERW pipe is made by forming hot-rolled strip into a tube and welding the longitudinal seam by high-frequency induction without filler metal; the weld bead is scarfed flush inside and out and the seam is annealed. "MS pipe" (mild steel pipe) is the Gulf and Indian name for the same product in black (unpainted, lightly oiled) finish. It is the workhorse pipe for structures, scaffolding, fences, low-pressure water and air lines, fire-fighting sprinkler mains and conduit. For pressures above 20 bar, high temperatures or sour service, seamless pipe is specified instead — the comparison is in section 8.
Pipe pages
Related pipe products each have their own page: DKP pipe (bright cold-rolled precision tube for furniture and plating), ASTM A53 pipe (Grade B sch 40 / 80 for US-spec projects), galvanized pipe and, for pressure and machine use, seamless pipe.
Size chart — NPS, OD, wall and weight
Nominal pipe size (NPS, inches) is a trade name, not a dimension: 2" pipe has an outside diameter of 60.3 mm. Weight per metre is calculated as (OD − wall) × wall × 0.02466 kg; a 6 m bar of 2" × 3.2 mm weighs 27 kg. Walls in the table are our stock; other walls to EN 10219 or A53 schedule 40/80 on mill order.
| NPS | OD (mm) | Wall (mm) | kg/m | kg per 6 m |
|---|---|---|---|---|
| ½" | 21.3 | 1.5 | 0.73 | 4.39 |
| ½" | 21.3 | 1.9 | 0.91 | 5.45 |
| ½" | 21.3 | 2 | 0.95 | 5.71 |
| ½" | 21.3 | 2.5 | 1.16 | 6.95 |
| ¾" | 26.9 | 1.5 | 0.94 | 5.64 |
| ¾" | 26.9 | 1.9 | 1.17 | 7.03 |
| ¾" | 26.9 | 2 | 1.23 | 7.37 |
| ¾" | 26.9 | 2.4 | 1.45 | 8.7 |
| ¾" | 26.9 | 2.5 | 1.5 | 9.02 |
| ¾" | 26.9 | 3 | 1.77 | 10.61 |
| 1" | 33.7 | 1.5 | 1.19 | 7.15 |
| 1" | 33.7 | 1.9 | 1.49 | 8.94 |
| 1" | 33.7 | 2 | 1.56 | 9.38 |
| 1" | 33.7 | 2.4 | 1.85 | 11.11 |
| 1" | 33.7 | 2.5 | 1.92 | 11.54 |
| 1" | 33.7 | 3 | 2.27 | 13.63 |
| 1" | 33.7 | 3.2 | 2.41 | 14.44 |
| 1" | 33.7 | 3.6 | 2.67 | 16.03 |
| 1" | 33.7 | 4 | 2.93 | 17.58 |
| 1¼" | 42.4 | 1.4 | 1.42 | 8.49 |
| 1¼" | 42.4 | 1.5 | 1.51 | 9.08 |
| 1¼" | 42.4 | 1.9 | 1.9 | 11.39 |
| 1¼" | 42.4 | 2 | 1.99 | 11.96 |
| 1¼" | 42.4 | 2.5 | 2.46 | 14.76 |
| 1¼" | 42.4 | 3 | 2.92 | 17.49 |
| 1¼" | 42.4 | 3.2 | 3.09 | 18.56 |
| 1¼" | 42.4 | 3.6 | 3.45 | 20.67 |
| 1¼" | 42.4 | 4 | 3.79 | 22.73 |
| 1½" | 48.3 | 1.4 | 1.62 | 9.71 |
| 1½" | 48.3 | 1.5 | 1.73 | 10.39 |
| 1½" | 48.3 | 1.9 | 2.17 | 13.04 |
| 1½" | 48.3 | 2 | 2.28 | 13.7 |
| 1½" | 48.3 | 2.4 | 2.72 | 16.3 |
| 1½" | 48.3 | 2.5 | 2.82 | 16.94 |
| 1½" | 48.3 | 3 | 3.35 | 20.11 |
| 1½" | 48.3 | 3.2 | 3.56 | 21.35 |
| 1½" | 48.3 | 3.6 | 3.97 | 23.81 |
| 1½" | 48.3 | 4 | 4.37 | 26.22 |
| 1½" | 48.3 | 5 | 5.34 | 32.03 |
| 2" | 60.3 | 1.5 | 2.18 | 13.05 |
| 2" | 60.3 | 1.9 | 2.74 | 16.42 |
| 2" | 60.3 | 2 | 2.88 | 17.25 |
| 2" | 60.3 | 2.4 | 3.43 | 20.56 |
| 2" | 60.3 | 2.5 | 3.56 | 21.38 |
| 2" | 60.3 | 2.9 | 4.11 | 24.63 |
| 2" | 60.3 | 3 | 4.24 | 25.43 |
| 2" | 60.3 | 3.2 | 4.51 | 27.04 |
| 2" | 60.3 | 3.6 | 5.03 | 30.2 |
| 2" | 60.3 | 4 | 5.55 | 33.32 |
| 2" | 60.3 | 5 | 6.82 | 40.91 |
| 2½" | 76.1 | 1.5 | 2.76 | 16.55 |
| 2½" | 76.1 | 2 | 3.66 | 21.93 |
| 2½" | 76.1 | 2.4 | 4.36 | 26.17 |
| 2½" | 76.1 | 2.5 | 4.54 | 27.22 |
| 2½" | 76.1 | 2.9 | 5.24 | 31.41 |
| 2½" | 76.1 | 3 | 5.41 | 32.45 |
| 2½" | 76.1 | 3.2 | 5.75 | 34.52 |
| 2½" | 76.1 | 3.6 | 6.44 | 38.62 |
| 2½" | 76.1 | 4 | 7.11 | 42.67 |
| 2½" | 76.1 | 5 | 8.77 | 52.6 |
| 3" | 88.9 | 1.5 | 3.23 | 19.4 |
| 3" | 88.9 | 2 | 4.29 | 25.72 |
| 3" | 88.9 | 2.5 | 5.33 | 31.96 |
| 3" | 88.9 | 2.9 | 6.15 | 36.9 |
| 3" | 88.9 | 3 | 6.36 | 38.13 |
| 3" | 88.9 | 3.6 | 7.57 | 45.44 |
| 3" | 88.9 | 4 | 8.38 | 50.25 |
| 3" | 88.9 | 5 | 10.35 | 62.07 |
| 3" | 88.9 | 6 | 12.27 | 73.6 |
| 3½" | 101.6 | 2 | 4.91 | 29.47 |
| 3½" | 101.6 | 2.5 | 6.11 | 36.66 |
| 3½" | 101.6 | 3 | 7.29 | 43.76 |
| 3½" | 101.6 | 3.6 | 8.7 | 52.2 |
| 3½" | 101.6 | 4 | 9.63 | 57.76 |
| 3½" | 101.6 | 5 | 11.91 | 71.47 |
| 3½" | 101.6 | 6 | 14.15 | 84.87 |
| 4" | 114.3 | 2 | 5.54 | 33.23 |
| 4" | 114.3 | 2.5 | 6.89 | 41.35 |
| 4" | 114.3 | 3 | 8.23 | 49.4 |
| 4" | 114.3 | 3.6 | 9.83 | 58.97 |
| 4" | 114.3 | 4 | 10.88 | 65.28 |
| 4" | 114.3 | 5 | 13.48 | 80.86 |
| 4" | 114.3 | 6 | 16.02 | 96.14 |
| 4" | 114.3 | 6.3 | 16.78 | 100.67 |
| 5" | 139.7 | 2.5 | 8.46 | 50.75 |
| 5" | 139.7 | 3 | 10.11 | 60.68 |
| 5" | 139.7 | 4 | 13.39 | 80.31 |
| 5" | 139.7 | 5 | 16.61 | 99.65 |
| 5" | 139.7 | 6 | 19.78 | 118.69 |
| 5" | 139.7 | 8 | 25.98 | 155.89 |
| 6" | 168.3 | 3 | 12.23 | 73.37 |
| 6" | 168.3 | 4 | 16.21 | 97.24 |
| 6" | 168.3 | 5 | 20.14 | 120.81 |
| 6" | 168.3 | 6 | 24.01 | 144.08 |
| 6" | 168.3 | 8 | 31.62 | 189.74 |
| 8" | 219.1 | 3 | 15.99 | 95.92 |
| 8" | 219.1 | 4 | 21.22 | 127.3 |
| 8" | 219.1 | 5 | 26.4 | 158.39 |
| 8" | 219.1 | 6 | 31.53 | 189.18 |
| 8" | 219.1 | 8 | 41.65 | 249.88 |
| 10" | 273 | 4 | 26.53 | 159.2 |
| 10" | 273 | 5 | 33.04 | 198.26 |
| 10" | 273 | 6 | 39.51 | 237.03 |
| 10" | 273 | 8 | 52.28 | 313.67 |
| 10" | 273 | 10 | 64.86 | 389.14 |
| 12" | 323.3 | 5 | 39.25 | 235.48 |
| 12" | 323.3 | 6 | 46.95 | 281.69 |
| 12" | 323.3 | 8 | 62.2 | 373.21 |
EN 10219 / EN 10255 / ASTM A53 dimensions; plain or bevelled ends; 6 m standard, 12 m on request.
Which standard: EN 10219, EN 10255 or ASTM A53?
For a warehouse frame the fabricator wants EN 10219 S235JRH or S355J2H; for a water or sprinkler line the contractor wants EN 10255 medium series (or A53 Grade B, which is dual-certified on most heats) with threaded ends. We stock both and state the standard on the certificate.
| Standard | Purpose | Grades | Test | Ends | Typical buyer |
|---|---|---|---|---|---|
| EN 10219 | Structural (frames, trusses, columns) | S235JRH, S275J0H, S355J2H | Dimensional, tensile, flattening | Plain | Steel-building fabricators, EU/Balkans |
| EN 10255 | Water, gas, compressed air (threadable) | S195T, Light/Medium/Heavy series | Hydrostatic 50 bar, leak test | Plain, bevelled, threaded + socket | Plumbing, fire-fighting, Gulf/Iraq |
| ASTM A53 Gr. B | Mechanical and pressure, general | Grade A (205 MPa), Grade B (240 MPa) | Hydro, flattening, bend | Plain, bevelled (Sch 40/80) | Contractors, oil & gas utilities, Africa |
| EN 10217-1 | Pressure (boilers, vessels) | P235TR1/TR2 | Hydro, NDT of weld | Bevelled | Process plants |
Grades and mechanical properties
| Grade | Standard | Yield min (MPa) | Tensile (MPa) | Elongation | Notes |
|---|---|---|---|---|---|
| S195T | EN 10255 | 195 | 320–520 | 20% | Threadable water/gas series |
| S235JRH | EN 10219 | 235 | 360–510 | 24% | General structural |
| S355J2H | EN 10219 | 355 | 470–630 | 20% | Impact 27 J at −20 °C |
| Grade B | ASTM A53 | 240 | 415 min | — | Dual-marked with A500 Gr. B where applicable |
| P235TR2 | EN 10217-1 | 235 | 360–500 | 25% | Pressure, impact-tested |
Ends, coating and finish
Plain square-cut ends are standard; bevelled 30° for welding; threaded BSPT to EN 10226 with a socket per bar for the EN 10255 series. Black pipe is delivered with a light mill oil or, for sea voyages over 14 days, a black bituminous or red-oxide varnish. For hot-dip galvanized (GI) pipe see the galvanized pipe page — same mill, zinc to EN 10240 A1.
- Plain ends, square cut, deburred
- Bevelled ends 30° +5/−0°, root face 1.6 mm
- Threaded BSPT + socket, plastic thread protectors
- Varnish, red-oxide primer or bare oiled
Pressure rating and testing
Every EN 10255 and A53 bar is hydrostatically tested (50 bar for EN 10255, per formula P = 2St/D for A53, minimum 5 seconds) and eddy-current tested on the weld. Working pressure of 2" medium-series pipe is 16 bar cold water; of 4" A53 Grade B Sch 40, about 40 bar at 20 °C with a 3:1 factor. Steam and hot-oil service require seamless or EN 10217 pressure pipe.
Scaffold, fence and structural tube
48.3 × 3.2 mm (1½") to EN 39 / BS 1139 is the scaffold tube standard — black or galvanized, 6 m, 3.56 kg/m. Fence posts use 42.4–60.3 mm; canopy and greenhouse frames 33.7–76.1 mm S235JRH; truss chords 88.9–168.3 mm S355J2H. All are cut to length and can be drilled or laser-slotted on our lines.
ERW vs seamless pipe
Where the spec says A106 or EN 10216 you need seamless; where it says A53, EN 10255 or EN 10219, ERW is correct and cheaper. See the seamless pipe page for stocked schedules.
| ERW (welded) | Seamless | |
|---|---|---|
| Manufacture | Strip formed and HF-welded | Pierced billet, no seam |
| Wall uniformity | ±10%, very even | ±12.5%, eccentric possible |
| Sizes | ½"–24", wall to 12 mm | ⅛"–24", wall to 60 mm |
| Pressure / temperature | To ~40 bar, ambient to 200 °C | High pressure, high temperature, sour |
| Price | 1.00 | 1.25–1.60 |
| Typical use | Structures, water, fire, scaffold, low-pressure gas | Boilers, process, hydraulics, API lines |
MS pipe price per ton
Indicative FOB Istanbul bands from our weekly export list, EN 10219 S235JRH black, 1"–4", 2–4 mm wall, 6 m bars, full-container quantities. Thin-wall small pipe (½"–¾", 1.5–2 mm) costs 10–20% more per ton; threaded-and-socketed EN 10255 adds 4–7%; A53 Grade B with hydro test and bevel 3–5%.
Bands from our weekly export list (September 2026), FOB Istanbul, full-container quantities, excluding freight and certificates. Firm price per project on RFQ within one working day.
Export and packing
Hexagonal bundles of 300–1 500 kg strapped in three places, thread protectors on threaded pipe, varnish for long voyages. 6 m pipe loads into 20' and 40' containers; 12 m only into 40' HC. HS code 7306.30 (welded, circular, iron or non-alloy steel).
| Term | Detail |
|---|---|
| MOQ | 1 × 20' container (≈20 t) or 1 truck (22–24 t); sizes can be mixed |
| Incoterms | FOB Istanbul · CIF / CFR Gulf, Red Sea, Africa · DAP EU, Balkans, Iraq, Caucasus |
| Lead time | Stock 5–10 working days; mill order 2–4 weeks |
| Packing | Hex bundles 300–1 500 kg, 3 straps; thread protectors; varnish for sea |
| Container / truck | 20' ≈ 20 t (6 m) · 40' HC ≈ 24–25 t (6 or 12 m) · truck 22–24 t |
| Documents | Invoice, packing list per bundle, EN 10204 3.1 with hydro test, certificate of origin; SASO, SONCAP, COC, EAC on request |
| Payment | 30% advance, balance against B/L copy; L/C at sight via London office |
Certificates
EN 10204 3.1 per heat with hydrostatic and eddy-current test records; certificate of origin; SASO/SABER, SONCAP, COC (Iraq), EAC on request; third-party inspection in Dilovası before loading.
How to order
Send NPS or OD × wall, standard (EN 10219 / EN 10255 / A53), end finish, length, quantity in tons or bars and the port. We answer within one working day with price, bundle list, gross weight and containers; stock sizes load in 5–10 working days.
Standards
- EN 10219-1/-2 (structural, S235JRH–S355J2H)
- EN 10255 (medium / heavy series, water & gas)
- ASTM A53 / A53M Grade A/B Type E
- ASTM A500 (structural round)
- EN 10217-1 (pressure, P235TR1/TR2)
- API 5L Grade B (on request)
Grades
Grade data sheets (chemistry, mechanicals, equivalents) are on our reference site: S235JR / S235JRH · S355J2 · A106 Grade B (seamless)
Frequently asked questions
What does MS pipe mean?
Mild steel pipe — low-carbon ERW black steel pipe in structural (EN 10219 / A500) or water-gas (EN 10255 / A53) grades. It is the same product as ERW pipe or black pipe; GI pipe is the hot-dip galvanized version.
What is the difference between GI and MS pipe?
MS (black) pipe is bare or varnished carbon steel; GI pipe is the same pipe hot-dip galvanized with 55–80 µm of zinc for water lines and outdoor use. GI costs about 20–30% more per ton and lasts 20–40 years in fresh water where black pipe rusts in 5–10.
What is the thickness of MS pipe?
From 1.5 mm on ½"–1" light pipe to 8 mm on 8"–12"; EN 10255 medium series is 2.6 mm (½") to 4.5 mm (6"), A53 Sch 40 is 2.77 mm (½") to 8.18 mm (8"). The size chart above lists every stocked OD × wall.
What is the difference between MS pipe and CR pipe?
MS/ERW pipe is made from hot-rolled strip (rougher surface, 1.5 mm and up, structural and pressure use); CR (cold-rolled) tube is made from cold-rolled strip in thin walls 0.6–2 mm for furniture, appliances and precision work (EN 10305-3). CR is smoother and more expensive per ton.
What is the price of MS pipe per ton?
See the indicative FOB Istanbul band above for 1"–4" S235JRH; small thin-wall sizes and threaded EN 10255 pipe sit above it, large-diameter 6"–12" around it. The firm price depends on size mix, quantity and port and is quoted within one working day.
Is ERW pipe suitable for water and gas?
Yes when made to EN 10255 (medium or heavy series) or ASTM A53, which include a 50 bar hydrostatic test and threadable ends; many national codes require galvanized pipe for potable water. Structural EN 10219 pipe is not tested for pressure.
How many 6 m pipes fit in a 20-foot container?
By weight about 20 t: for 2" × 3.2 mm (27 kg per bar) about 740 bars; for 4" × 4 mm (66 kg) about 300 bars. Bundles are chocked to fill the container width.
Can you supply pipe cut to length, drilled or bevelled?
Yes — cut ±2 mm, bevelled for welding, threaded BSPT/NPT, drilled or laser-slotted to DXF, and bent to radius on our section bender for handrail and canopy work.