A387 Gr.11
Data verifiedASTM A387 Grade 11 is the 1.25Cr-0.5Mo pressure-vessel plate for elevated-temperature service in refineries and petrochemical plant. Class 2 is the higher-strength, tempered condition normally specified for reactors and separators.
Chemical composition
| Element | Content (%) |
|---|---|
| C | 0.05–0.17 |
| Si | 0.50–0.80 |
| Mn | 0.40–0.65 |
| P | ≤0.025 |
| S | ≤0.025 |
| Cr | 1.00–1.50 |
| Mo | 0.45–0.65 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Yield strength | ≥310 MPa (Class 2) |
| Tensile strength | 515–690 MPa (Class 2) |
| Density | 7.85 g/cm³ |
Heat treatment
Supplied normalized and tempered (Class 2: temper ≥620 °C). PWHT is standard after welding.
Equivalent grades
| Standard | Designation |
|---|---|
| din | 13CrMo4-5 (near) |
| aisi | A387 Gr.11 Cl.2 |
| jis | SCMV3 (near) |
| gb | 15CrMoR (near) |
Compare side by side: A387 Gr.11 vs 13CrMo4-5
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Refinery vessels, hydrotreaters, separators, hot oil systems, hydrogen service (within Nelson-curve limits).
Processing: Weld with 1.25Cr-0.5Mo consumables, preheat 150–250 °C by thickness, and PWHT — Cr-Mo welds are not left as-welded in code service.
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Ask for a quotationVisit NasteelSource: ASTM A387 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.