API 5L X80
Data verifiedAPI 5L X80 is the highest-strength line pipe in routine production, used on flagship projects such as China’s West–East Gas Pipeline 3 and 4. It maximizes throughput per tonne of steel where the project can support its welding and handling discipline.
Chemical composition
| Element | Content (%) |
|---|---|
| C | ≤0.24 (PSL2) |
| Si | ≤0.45 |
| Mn | ≤1.85 (PSL2) |
| P | ≤0.025 |
| S | ≤0.015 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Yield strength | ≥555 MPa (80,000 psi) |
| Tensile strength | 625–825 MPa (PSL2) |
| Density | 7.85 g/cm³ |
Heat treatment
TMCP with accelerated cooling; production limited to qualified mills with proven DWTT and toughness performance.
Equivalent grades
| Standard | Designation |
|---|---|
| din | L555 (near) |
| aisi | API 5L X80 (PSL2) |
| gb | L555 (GB/T 9711) |
Compare side by side: API 5L X80 vs API 5L X70
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Ultra-high-pressure gas trunk lines, large-diameter long-distance pipelines.
Processing: Requires qualified mechanized welding procedures and careful pipe handling; not every fabricator is approved for X80.
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Ask for a quotationVisit NasteelSource: API 5L published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.