A387 Gr.11 vs 13CrMo4-5
These two grades are listed as equivalents of each other: their chemistry windows overlap and they serve the same applications. They are not always identical — check the differences below before substituting, especially in certified designs.
A387 Gr.11
Structural & HSLA Steel
ASTM 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.
Standards: DIN 13CrMo4-5 (near) · AISI A387 Gr.11 Cl.2 · JIS SCMV3 (near) · GB 15CrMoR (near)
13CrMo4-5
Structural & HSLA Steel
13CrMo4-5 is the EN 10028-2 1Cr-0.5Mo creep-resisting plate for boilers, hot vessels and power piping. It is the European near-counterpart of ASTM A387 Grades 11/12 and China’s 15CrMo family.
Standards: DIN 1.7335 (13CrMo4-5) · AISI A387 Gr.11/12 (near) · JIS SCMV3 (near) · GB 15CrMoG / 15CrMoR (near)
Chemical composition compared (%)
| Element | A387 Gr.11 | 13CrMo4-5 |
|---|---|---|
| C | 0.05–0.17 | 0.08–0.18 |
| Si | 0.50–0.80 | ≤0.35 |
| Mn | 0.40–0.65 | 0.40–1.00 |
| P | ≤0.025 | ≤0.025 |
| S | ≤0.025 | ≤0.010 |
| Cr | 1.00–1.50 | 0.70–1.15 |
| Mo | 0.45–0.65 | 0.40–0.60 |
Properties compared
| Property | A387 Gr.11 | 13CrMo4-5 |
|---|---|---|
| Yield strength | ≥310 MPa (Class 2) | ≥300 MPa (≤16 mm) |
| Tensile strength | 515–690 MPa (Class 2) | 450–600 MPa |
| Density | 7.85 g/cm³ | 7.85 g/cm³ |
| Service temperature | — | to ~570 °C |
Sourcing either grade?
Nasteel stocks both families from Shenzhen with EN 10204 3.1 mill certificates by heat number.
Ask for a quotationSee full data sheets: A387 Gr.11 · 13CrMo4-5. Substitution decisions for certified parts stay with the design authority.