What is seamless pipe?
Seamless pipe is made by piercing a hot billet on a rotary piercer and rolling or drawing it to size, so there is no weld: uniform properties around the circumference, full wall thickness at high pressure and temperature, and acceptance under boiler, refinery and pipeline codes that exclude or de-rate welded pipe (ASME B31.1/B31.3, PED, API). The price is 25–60% above ERW of the same size because of the process and the tighter chemistry; for water, structures and low-pressure lines ERW is the correct, cheaper choice — see the ERW pipe page and the comparison below.
Pipe pages
The seamless family has separate pages for boiler tubes (P235GH / P265GH / 16Mo3 to EN 10216-2, A192 / A210), ST52 seamless mechanical and hydraulic tube (E355, honed cylinder tube) and ASTM A53 Type S; stainless seamless is on the seamless stainless pipe page.
Standards and grades
| Standard | Grade | Yield / tensile (MPa) | Service | Typical use |
|---|---|---|---|---|
| ASTM A106 | Grade B (C) | 240 / 415 | High temperature to 425 °C | Refineries, power, steam, process (most stock) |
| ASTM A53 | Type S Gr. B | 240 / 415 | General pressure | Dual-certified with A106 B |
| API 5L | Grade B PSL1 / X42–X65 | 245–450 / 415–535 | Line pipe | Oil, gas and water pipelines |
| EN 10216-1 | P235TR2 / P265TR2 | 235–265 / 360–500 | Pressure, room temp., impact −20 °C | Process, pressure lines (EU / PED) |
| EN 10216-2 | P235GH / P265GH | 235–265 / 360–530 | Elevated temperature to 400 °C | Boilers, superheaters, steam (PED) |
| EN 10216-2 | 16Mo3 / 13CrMo4-5 | 275–290 / 440–590 | To 500–550 °C | Boilers, hot-oil, petrochemical |
| EN 10210-1 | S355J2H | 355 / 470–630 | Structural, hot-finished | Piles, structures, cranes |
| EN 10305-1 | E235 / E355 +C / +N | 235–355 | Precision, cold-drawn | Hydraulic cylinders, machinery, automotive |
Sizes: stocked schedules
Stocked sizes above (OD × wall × kg/m); the full ASME B36.10M schedule range is available on order.
| NPS | OD (mm) | Wall (mm) | kg/m |
|---|---|---|---|
| ½" | 21.3 | 2 | 0.95 |
| ½" | 21.3 | 7.1 | 2.49 |
| ¾" | 26.9 | 2.3 | 1.4 |
| ¾" | 26.9 | 6.3 | 3.2 |
| 1" | 33.7 | 2.6 | 1.99 |
| 1" | 33.7 | 7.1 | 4.66 |
| 1¼" | 42.4 | 3.2 | 3.09 |
| 1½" | 48.3 | 3.2 | 3.56 |
| 1½" | 48.3 | 9.53 | 9.11 |
| 2" | 60.3 | 3.6 | 5.03 |
| 2" | 60.3 | 9.53 | 11.93 |
| 2½" | 76.1 | 3.6 | 6.44 |
| 3" | 88.9 | 4 | 8.38 |
| 4" | 114.3 | 4.5 | 12.19 |
| 5" | 139.7 | 5 | 16.61 |
| 12" | 323.9 | 8 | 62.32 |
| 355.6 | 8 | 68.58 | |
| 457 | 9.53 | 105.16 | |
| 610 | 9.53 | 141.12 |
EN 10216-1/2 (P235TR2, P235GH) and ASTM A106 Gr. B; other schedules on mill order.
Schedule chart — OD, wall and weight
| NPS | OD (mm) | Sch 40 wall / kg/m | Sch 80 wall / kg/m | Sch 160 wall / kg/m | XXS wall / kg/m |
|---|---|---|---|---|---|
| ½" | 21.3 | 2.77 / 1.27 | 3.73 / 1.62 | 4.78 / 1.95 | 7.47 / 2.55 |
| ¾" | 26.7 | 2.87 / 1.69 | 3.91 / 2.20 | 5.56 / 2.90 | 7.82 / 3.64 |
| 1" | 33.4 | 3.38 / 2.50 | 4.55 / 3.24 | 6.35 / 4.24 | 9.09 / 5.45 |
| 1½" | 48.3 | 3.68 / 4.05 | 5.08 / 5.41 | 7.14 / 7.25 | 10.15 / 9.55 |
| 2" | 60.3 | 3.91 / 5.44 | 5.54 / 7.48 | 8.74 / 11.1 | 11.07 / 13.4 |
| 3" | 88.9 | 5.49 / 11.3 | 7.62 / 15.3 | 11.13 / 21.3 | 15.24 / 27.7 |
| 4" | 114.3 | 6.02 / 16.1 | 8.56 / 22.3 | 13.49 / 33.5 | 17.12 / 41.0 |
| 6" | 168.3 | 7.11 / 28.3 | 10.97 / 42.6 | 18.26 / 67.6 | 21.95 / 79.2 |
| 8" | 219.1 | 8.18 / 42.6 | 12.70 / 64.6 | 23.01 / 111 | 22.23 / 108 |
| 10" | 273.0 | 9.27 / 60.3 | 15.09 / 96.0 | 28.58 / 172 | 25.40 / 155 |
| 12" | 323.9 | 10.31 / 79.7 | 17.48 / 132 | 33.32 / 239 | 25.40 / 187 |
| 16" | 406.4 | 12.70 / 123 | 21.44 / 204 | 40.49 / 365 | — |
| 20" | 508.0 | 15.09 / 183 | 26.19 / 311 | 50.01 / 565 | — |
| 24" | 610.0 | 17.48 / 255 | 30.96 / 442 | 59.54 / 808 | — |
ERW vs seamless
| Seamless | ERW welded | |
|---|---|---|
| Weld | None | HF seam, heat-treated |
| Pressure / temperature | High; ASME B31 without joint factor | Moderate; joint efficiency 0.85–1.0 by code |
| Wall range | 2–60 mm, heavy schedules | 1.5–12 mm |
| Wall uniformity | ±12.5%, some eccentricity | ±10%, very even |
| Sizes | ⅛"–24" (larger on request) | ½"–24" |
| Cost | 1.25–1.60 | 1.00 |
| Specify for | Boilers, refineries, hydraulics, sour/high-pressure gas, A106/EN 10216 specs | Water, fire, structures, low-pressure gas, A53/EN 10255/EN 10219 specs |
Testing and certification
Every length is hydrostatically tested (or eddy-current / ultrasonic for EN 10216), with tensile, flattening and bend tests per heat; impact tests for TR2 / J2 grades; ultrasonic lamination check on request. Certificates EN 10204 3.1 standard, 3.2 (TÜV, BV, LR, DNV, SGS) for PED and ASME work; PED 2014/68/EU Annex I 4.3 approval on the mill; NACE MR0175 / HIC for sour service on request.
Ends, coating and processing
Bevelled 30° (ASME B16.25) for welding is standard on A106 / API 5L; plain ends for EN 10216 tubes; threaded NPT for small A106; hot-dip galvanized (A53 S) for water. We cut to length, bevel, groove, thread, bend (to 200 mm) and supply matching butt-weld fittings A234 WPB / EN 10253-2 and flanges A105 / EN 1092-1.
Seamless pipe price per ton
Indicative FOB Istanbul band from our weekly export list, A106 Grade B / P235GH ½"–6" Sch 40, 6 m bevelled, full-container quantities; Sch 80 and heavy schedules sit at the top of the band, 16Mo3 and API 5L PSL2 30–50% above, cold-drawn precision tube priced per size.
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
Bundles with end caps, varnish for sea; 6 m in 20' (20 t) and 40' HC (24–25 t); 12 m in 40' HC or by flat-rack for 16"+. HS code 7304.19 (line pipe), 7304.31/.39 (seamless, circular, non-alloy), 7304.51/.59 (alloy).
| Term | Detail |
|---|---|
| MOQ | 3 t per size; 1 × 20' for freight |
| Incoterms | FOB Istanbul · CIF / CFR Gulf, Red Sea, Africa · DAP EU, Balkans, Iraq, Caucasus · DAP Aktau |
| Lead time | ½"–12" Sch 40/80 stock 5–10 working days; other 3–6 weeks |
| Packing | Bundles with caps, 3 straps, varnish; heavy pipe single with slings |
| Container / truck | 20' ≈ 20 t (6 m) · 40' HC ≈ 24–25 t (6 / 12 m) · flat-rack 16"+ · truck 24 t |
| Documents | Invoice, packing list, EN 10204 3.1/3.2, PED / API documents, 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 (chemistry, tensile, hydro, NDT), 3.2 witnessed on request, PED material certificate, API monogram for API 5L from licensed mills, certificate of origin; SASO, SONCAP, COC, EAC arranged.
How to order
Send standard and grade, NPS × schedule (or OD × wall), length, ends, quantity, certificate level and port. Reply within one working day; stock sizes ship in 5–10 working days.
Standards
- ASTM A106 / A106M Grade B (high-temperature service)
- ASTM A53 Type S
- API 5L Grade B PSL1/PSL2
- EN 10216-1 (P235TR1/TR2, P265TR2)
- EN 10216-2 (P235GH, P265GH, 16Mo3, 13CrMo4-5)
- EN 10210-1 (S355J2H hot-finished structural)
- EN 10305-1 (cold-drawn precision tubes E235, E355)
- ASME B36.10M (schedules)
Grades
Grade data sheets (chemistry, mechanicals, equivalents) are on our reference site: A106 Grade B · P265GH · 16Mo3 · S355J2
Frequently asked questions
What is a seamless pipe?
Pipe made from a pierced and rolled billet with no weld seam, for high-pressure, high-temperature and code-governed service (boilers, refineries, hydraulics, pipelines) under A106, EN 10216, API 5L.
What is the difference between seamless and ERW pipe?
ERW is welded from strip — cheaper, very uniform wall, fine for water, fire, structures and low-pressure lines; seamless has no weld, thicker walls and full code acceptance at high pressure and temperature, at 25–60% more.
Is ASTM A106 seamless?
Yes — A106 covers seamless carbon steel pipe for high-temperature service (Grades A, B, C); Grade B is the standard. A53 can be seamless (Type S) or welded (Type E).
What is the difference between seamless pipe and MS pipe?
MS (mild steel) pipe usually means ERW black pipe for structures and water; seamless is a manufacturing route for pressure pipe. Both are carbon steel; the spec (A106 vs A53/EN 10255/EN 10219) tells you which is required.
What is P235GH tube?
EN 10216-2 seamless boiler and pressure tube, 235 MPa yield with guaranteed elevated-temperature strength to 400 °C and −20 °C impact — the European equivalent for A106 Gr A/B in PED boilers.
Which sizes are in stock?
½" to 12" Sch 40 and 80 in A106 Gr B / P235GH from stock; 14"–24", Sch 160/XXS, 16Mo3, API 5L PSL2 and cold-drawn precision tubes in 3–6 weeks.
Do you supply 3.2 certificates?
Yes — TÜV, BV, LR, DNV or SGS witness for PED and ASME work; NACE / HIC for sour service on request.
How much does seamless pipe cost?
See the indicative FOB Istanbul band above for A106 B / P235GH Sch 40; heavier schedules and alloy grades above it. Firm price within one working day.