A387 Gr.12
Data under reviewASTM A387 Grade 12 is the 1Cr-0.5Mo vessel plate, one step below Grade 11 in chromium and high-temperature strength. It serves moderately hot pressure equipment where full 1.25Cr alloy is not required.
Chemical composition
| Element | Content (%) |
|---|---|
| C | 0.05–0.17 |
| Si | 0.15–0.40 |
| Mn | 0.40–0.65 |
| P | ≤0.025 |
| S | ≤0.025 |
| Cr | 0.80–1.15 |
| Mo | 0.45–0.60 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Yield strength | ≥275 MPa (Class 2) |
| Tensile strength | 485–620 MPa (Class 2) |
| Density | 7.85 g/cm³ |
Heat treatment
Supplied normalized and tempered; PWHT after welding.
Equivalent grades
| Standard | Designation |
|---|---|
| din | 13CrMo4-5 (near) |
| aisi | A387 Gr.12 Cl.2 |
| jis | SCMV3 (near) |
| gb | 15CrMoR (near) |
Compare side by side: A387 Gr.12 vs A387 Gr.11
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Heat exchangers, steam drums, petrochemical vessels at moderate temperature.
Processing: As Grade 11: matched Cr-Mo filler, preheat and PWHT per code.
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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.