API 5L Grade B
Data verifiedAPI 5L Grade B is the entry grade of the pipeline specification — the most common line-pipe steel worldwide for low and medium-pressure oil, gas and water transmission. The letter B grade anchors the bottom of the X-grade strength ladder.
Chemical composition
| Element | Content (%) |
|---|---|
| C | ≤0.24 (PSL2) |
| Si | ≤0.40 |
| Mn | ≤1.20 (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 | ≥245 MPa (35,500 psi) |
| Tensile strength | 415–655 MPa (PSL2) |
| Density | 7.85 g/cm³ |
Heat treatment
As-rolled, normalized or TMCP per API 5L delivery condition; no hardening.
Equivalent grades
| Standard | Designation |
|---|---|
| din | L245 (EN 10208, near) |
| aisi | API 5L B (PSL2) |
| gb | L245 (GB/T 9711) |
Compare side by side: API 5L Grade B vs API 5L X42
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Gathering lines, water pipelines, low-pressure gas distribution, structural pipe.
Processing: Excellent weldability (low CE); welded pipe to API 5L with full-body testing per PSL level ordered.
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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.