API 5L X70 Line Pipe Carbon Steel — Factory Direct Supplier
API 5L X70 is a high-strength, low-alloy carbon steel line pipe designed for long-distance oil and gas transmission pipelines. With a minimum yield strength of 485 MPa (70,000 psi), X70 sits between X65 and X80 in the API 5L strength hierarchy and is the most widely specified high-strength grade for large-diameter onshore pipelines worldwide.
Huaxia-Steel supplies API 5L X70 line pipe in both seamless (SMLS) and welded (LSAW, HFW) forms, covering diameters from 2 inches to 56 inches, in PSL1 and PSL2 quality levels with full traceability and EN 10204 3.1/3.2 MTC.
Product Overview
| Parameter | Specification |
|---|---|
| Standard | API 5L / ISO 3183 |
| Grade | X70 (L485) |
| Yield strength, min | 485 MPa (70,000 psi) |
| Tensile strength, min | 570 MPa (82,700 psi) |
| Yield-to-tensile ratio, max | 0.93 (PSL2) |
| Elongation, min | 14% (varies by diameter) |
| Manufacturing types | Seamless (SMLS), LSAW, HFW |
| Product specification level | PSL1 and PSL2 |
| Delivery condition | As-rolled, normalized, or TMCP |
Dimensional Specifications
Seamless Pipe (SMLS)
| NPS (inch) | OD (mm) | Wall thickness (mm) | Weight (kg/m) |
|---|---|---|---|
| 6 | 168.3 | 4.78-12.7 | 19.3-48.8 |
| 8 | 219.1 | 5.54-15.1 | 29.3-76.2 |
| 10 | 273.1 | 6.35-17.5 | 42.0-110.5 |
| 12 | 323.9 | 7.14-19.1 | 56.0-145.2 |
| 16 | 406.4 | 9.53-25.4 | 94.0-238.7 |
Welded Pipe (LSAW / HFW)
| NPS (inch) | OD (mm) | Wall thickness (mm) | Manufacturing |
|---|---|---|---|
| 20 | 508.0 | 6.35-25.4 | LSAW / HFW |
| 24 | 610.0 | 7.92-30.0 | LSAW / HFW |
| 30 | 762.0 | 9.53-30.0 | LSAW |
| 36 | 914.0 | 9.53-30.0 | LSAW |
| 42 | 1067.0 | 12.7-30.0 | LSAW |
| 48 | 1219.0 | 12.7-30.0 | LSAW |
Chemical Composition (PSL2, Heat Analysis)
| Element | Max % | Notes |
|---|---|---|
| C | 0.22 | Carbon, lower for weldability |
| Mn | 1.65 | Manganese, solid solution strengthener |
| P | 0.025 | Phosphorus, limited for toughness |
| S | 0.015 | Sulfur, very tight for HIC resistance |
| Si | 0.45 | Silicon, deoxidizer |
| Nb (Cb) | 0.06 | Columbium, microalloy |
| V | 0.06 | Vanadium, microalloy |
| Ti | 0.04 | Titanium, microalloy |
| CEV (IIW) | 0.43 | Carbon equivalent for weldability |
| CEV (Pcm) | 0.25 | Welding crack parameter |
Manufacturing Standards
- API 5L (46th Edition): Specification for line pipe
- ISO 3183: International equivalent of API 5L
- PSL2 requirements: Mandatory Charpy V-notch impact testing, CVN absorbed energy per API 5L Table 6
- Supplementary requirements: S2 (seamless), S3 (radiographic examination of welds), S4 (CVN at design temperature), S6 (DWT test for sour service)
- Coating options: FBE (fusion bonded epoxy), 3LPE (3-layer polyethylene), 3LPP (3-layer polypropylene)
Applications
- Onshore oil and gas transmission pipelines: Long-distance trunk lines, gathering lines
- Offshore pipeline risers: Platform risers, subsea flowlines (requires supplementary testing)
- Refinery and petrochemical piping: High-pressure hydrocarbon service
- CO2 transmission pipelines: Carbon capture and storage (CCS) applications
- Hydrogen pipelines: Emerging applications for hydrogen transport (requires special chemistry control)
Quality Assurance
- 100% hydrostatic testing at 95 percent of specified minimum yield strength (SMYS)
- 100% UT examination of weld seam (for welded pipe)
- 100% visual and dimensional inspection
- Charpy V-notch impact testing at 0 degrees C or design temperature (PSL2)
- DWT (drop weight tear) test for sour service per NACE TM0284
- Hardness testing: maximum 250 HV10 for sour service
- Traceability: heat number, batch number, and full production record
Packaging and Shipping
- End protection: Plastic or steel end caps for pipe ends
- Coating protection: Spiral wrap or outer wrap for coated pipe
- Bundling: Pipe bundles strapped with steel bands, 3-5 bands per bundle
- Marking: Size, grade, heat number, manufacturer name per API 5L Section 12
- Container loading: 20ft (max 6m length), 40ft (max 12m length), or break-bulk for large diameter
- Inland transport: Truck, rail, or barge to port
Why Choose Huaxia-Steel?
- Mill-direct pricing from Chinese API 5L-certified pipe mills
- Full PSL2 compliance with mandatory impact testing and NDE
- EN 10204 3.1 MTC included; 3.2 with SGS/BV/Intertek witnessing available
- Coating options: FBE, 3LPE, 3LPP applied at partner coating facilities
- Experienced in API 5L X70 projects in Middle East, Africa, Southeast Asia, and South America
- Flexible order quantities: from 10 tons (stock) to 5,000+ tons (project)
FAQ
What is the difference between API 5L X70 PSL1 and PSL2?
PSL1 has basic requirements for chemistry, tensile testing, and visual inspection. PSL2 adds mandatory CVN impact testing, tighter S/P limits, maximum yield-to-tensile ratio, and traceability requirements. PSL2 is required for pipelines in sour service, offshore, or low-temperature environments.
What is the maximum diameter available?
Seamless X70 pipe is available up to 26 inches (660 mm) OD. LSAW welded pipe is available up to 56 inches (1422 mm) OD. HFW welded pipe is available up to 24 inches (610 mm) OD.
Can X70 pipe be used for sour service?
Yes. X70 pipe for sour service must meet NACE TM0175/HIC requirements, including sulfur max 0.005 percent, calcium treatment for inclusion shape control, and DWT testing per NACE TM0284. Order as “API 5L X70QS” (Q = quality, S = sour service).
Get a Quote
Contact Huaxia-Steel for API 5L X70 line pipe with factory-direct pricing, full PSL2 testing, and worldwide shipping. Send your project specifications, quantities, and destination port for a detailed quotation within 24 hours.
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