Chemical composition and mechanical properties of SA387 Grade91 Type1, an American grade of pressure vessel steel.
SA387 Grade91 Type1 Approximate Grade Lookup Table
SA387 Grade91 Type1 Chemical Composition
| Element | Analysis Category | Grade91 Type1 | ||||||||
| C | Smelting Analysis | 0.08-0.12 | ||||||||
| Finished Product Analysis | 0.06-0.15 | |||||||||
| Mn | Smelting Analysis | 0.30-0.60 | ||||||||
| Finished Product Analysis | 0.25-0.66 | |||||||||
| P,≤ | Smelting Analysis | 0.02 | ||||||||
| Finished Product Analysis | 0.025 | |||||||||
| S,≤ | Smelting Analysis | 0.01 | ||||||||
| Finished Product Analysis | 0.012 | |||||||||
| Si | Smelting Analysis | 0.20-0.50 | ||||||||
| Finished Product Analysis | 0.18-0.56 | |||||||||
| Cr | Smelting Analysis | 8.00-9.50 | ||||||||
| Finished Product Analysis | 7.90-9.60 | |||||||||
| Mo | Smelting Analysis | 0.85-1.05 | ||||||||
| Finished Product Analysis | 0.80-1.10 | |||||||||
| Ni | Smelting Analysis | 0.4 | ||||||||
| Finished Product Analysis | 0.43 | |||||||||
| V | Smelting Analysis | 0.18-0.25 | ||||||||
| Finished Product Analysis | 0.16-0.27 | |||||||||
| Nbᴮ | Smelting Analysis | 0.06-0.10 | ||||||||
| Finished Product Analysis | 0.05-0.11 | |||||||||
| B，≤ᶜ | ... | |||||||||
| N | Smelting Analysis | 0.030-0.070 | ||||||||
| Finished Product Analysis | 0.025-0.080 | |||||||||
| N/Al | ... | |||||||||
| Al，≤ᶜ | 0.02 | |||||||||
| Ti，≤ᶜ | 0.01 | |||||||||
| Zr，≤ᶜ | 0.01 | |||||||||
| W，≤ᶜ | ... | |||||||||
| Cu，≤ᶜ | ... | |||||||||
| Sb，≤ᶜ | ... | |||||||||
| As，≤ᶜ | ... | |||||||||
| Sn，≤ᶜ | ... | |||||||||
A:For steel plates with a thickness greater than 5 inches (125 mm), the carbon content in the finished product analysis should not exceed 0.17%.
B:Cb and Nb are interchangeable and commonly used names for the same element, and both names are applicable to the (ASTM) "A101" standard.
C:Both smelting analysis and finished product analysis are applicable.
SA387 Grade91 Type1 Mechanical Properties
Tensile properties of Class II steel plates
| Tensile strength(MPa) | 585-760 | ||||||||||||||
| Yield strength (0.2% residual deformation), MPa ≥ | 415 | ||||||||||||||
| Elongation (gauge length 8 in. or 200 mm), %≥ | ... | ||||||||||||||
| Elongation (gauge length 8 in. or 50 mm), %≥ | 18 | ||||||||||||||
| Reduction of area,% | ... | ||||||||||||||
①Not applicable to annealed steel sheets
②For adjustments to elongation, please refer to the A20/A20M standard.
③Measurement using a round sample.
④Determination using flat specimens.
*Grade 91 steel plate is only applicable to Category 2 steel plates, see Section 1.3 — Translator's note