Carbon Steel Seamless Pipe — Factory Direct Supplier | Huaxia-Steel
Carbon steel seamless pipe is the backbone of oil and gas transport, structural piling, and mechanical tubing applications. Unlike welded pipe, seamless pipe has no longitudinal seam — making it stronger under pressure and more reliable in critical service.
Huaxia Steel supplies carbon steel seamless pipe to ASTM A106, A53, and API 5L standards, with mill-direct pricing and full certification.
Product Specifications
Size Range
| Parameter | Range |
|---|---|
| Outer diameter | 21.3–610 mm (1/2″–24″) |
| Wall thickness | 2.0–40 mm (SCH 10–SCH 160) |
| Length | 3–12 meters (random) or fixed |
| Ends | Plain, beveled, threaded |
Manufacturing Method
| Method | OD Range | Typical Standard |
|---|---|---|
| Hot-rolled (seamless) | 57–610 mm | ASTM A106, A53, API 5L |
| Cold-drawn (seamless) | 10–114 mm | ASTM A179, A192 |
| Hot-rolled + cold-drawn | 14–219 mm | DIN 2391, EN 10305 |
Available Grades
| Grade | Standard | C (%) | Yield (MPa) | Tensile (MPa) | Application |
|---|---|---|---|---|---|
| A53 Gr.B | ASTM A53 | 0.30 | 240 | 415 | General purpose, structural |
| A106 Gr.B | ASTM A106 | 0.30 | 240 | 415 | High-temp pressure service |
| A106 Gr.C | ASTM A106 | 0.35 | 275 | 485 | Higher-pressure service |
| API 5L Gr.B | API 5L | 0.28 | 245 | 415 | Oil & gas pipeline |
| API 5L X52 | API 5L | 0.28 | 360 | 460 | Pipeline, higher strength |
| St37.0 | DIN 1629 | 0.17 | 235 | 350–480 | Structural, mechanical |
| St52.0 | DIN 1629 | 0.20 | 355 | 490–630 | High-strength structural |
Dimensional Tolerances
Outer Diameter Tolerance
| OD (mm) | Hot-Rolled (±mm) | Cold-Drawn (±mm) |
|---|---|---|
| ≤30 | 0.50 | 0.15 |
| 30–50 | 0.60 | 0.20 |
| 50–114 | 0.80 | 0.30 |
| 114–219 | 1.20 | — |
| 219–610 | 1.60 | — |
Wall Thickness Tolerance
| Wall (mm) | Tolerance |
|---|---|
| ≤3 | +15% / −10% |
| 3–10 | +12.5% / −10% |
| >10 | +10% / −7.5% |
Surface and End Treatment Options
| Option | Description | Price Impact |
|---|---|---|
| Black (as-rolled) | Mill oxide surface | Base |
| Pickled & oiled | Acid-descaled, oiled | +3–5% |
| Galvanized | Hot-dip zinc, 55–85 µm | +25–32% |
| Varnished | Anti-corrosion coating | +2–4% |
| Beveled ends | 30° ±2.5° for welding | Included |
| Threaded & coupled | NPT or BSPT threads | +5–8% |
Quality Assurance
Every shipment includes:
- **Mill Test Certificate (MTC)** per EN 10204 3.1 — chemistry, mechanical properties, hydrotest results
- **Dimensional inspection report** — OD, WT, length at 3 locations per 100 pipes
- **Non-destructive testing** — UT or eddy current per ASTM E213/E309 (on request)
- **Hydrostatic test** — tested at 50% of yield stress or per standard
- **Third-party inspection** — SGS, BV, TUV available on request
Packaging and Shipping
| Package Type | Description |
|---|---|
| Bundle | 3–6 m lengths, strapped in hexagonal bundles (1–5 tons) |
| Wooden case | For small OD cold-drawn pipe |
| Container loading | 20’/40′ GP, 20–28 tons per container |
| Marking | Size, grade, heat number, standard painted on each pipe |
FOB Pricing (2025–2026, Shanghai/Tianjin)
| Grade | Size | FOB ($/ton) | MOQ |
|---|---|---|---|
| A106 Gr.B | 2″ SCH40 | 850–980 | 5 tons |
| A106 Gr.B | 6″ SCH40 | 780–890 | 5 tons |
| A53 Gr.B | 4″ SCH40 | 720–820 | 5 tons |
| API 5L Gr.B | 8″ SCH20 | 750–850 | 10 tons |
| St52.0 | 114×6 mm | 820–950 | 5 tons |
*Prices are indicative. Request a formal quote for current pricing.*
FAQ
**Q: What is the difference between seamless and welded pipe?**
A: Seamless pipe is formed from a solid billet with no weld seam. Welded pipe is formed from a flat plate and welded longitudinally. Seamless pipe has higher pressure rating (no weak seam) and better dimensional accuracy for critical applications. Welded pipe is 15–25% cheaper.
**Q: What is the delivery time for seamless pipe?**
A: Stock items: 7–10 days. Mill rolling (non-stock sizes): 25–45 days depending on size and quantity.
**Q: Can you supply seamless pipe with 3LPE coating?**
A: Yes. We can arrange 3-layer PE coating (epoxy + adhesive + PE outer layer) per DIN 30670 for buried pipeline applications. Add 8–12 days to lead time.
Get a Quote for Carbon Steel Seamless Pipe
**[Contact Huaxia Steel →](https://www.huaxia-steel.com/contact/)** — specify grade, OD, wall thickness, length, quantity, and destination port. We will send a formal quotation with FOB pricing and lead time within 24 hours.
