This specification covers manganese-molybdenum and manganese-molybdenum-nickel alloy steel plates intended particularly for welded boilers and other pressure vessels.Plates under this specification are available in four grades having different strength levels.The maximum thickness of plates is limited only by the capacity of the chemical composition to meet the specified mechanical property requirements. The minimum thickness is limited to 0.25 in. [6.5 mm].
| Grades | Description |
|---|---|
| Grade A | - |
| Grade B | - |
| Grade C | - |
| Grade D | - |
| Grade | Carbon, maxA | Manganese | Phosphorus,max | Sulfur,max | Silicon | Molybdenum | Nickel | ||
|---|---|---|---|---|---|---|---|---|---|
| Up to 1 in. [25 mm], incl, in thickness | Over 1 to 2 in. [50 mm], incl | Over 2 in. [50 mm] in thickness | |||||||
| Grade A | 0.20 | 0.23 | 0.25 | 0.87–1.41 | 0.025 | 0.025 | 0.13–0.45 | 0.41–0.64 | - |
| Grade B | 0.20 | 0.23 | 0.25 | 1.07–1.62 | 0.025 | 0.025 | 0.13–0.45 | 0.41–0.64 | - |
| Grade C | 0.20 | 0.23 | 0.25 | 1.07–1.62 | 0.025 | 0.025 | 0.13–0.45 | 0.41–0.64 | 0.37–0.73 |
| Grade D | 0.20 | 0.23 | 0.25 | 1.07–1.62 | 0.025 | 0.025 | 0.13–0.45 | 0.41–0.64 | 0.67–1.03 |
| Grades |
Tensile strength,min: ksi [MPa] |
Yield strength,min: ksi [MPa] |
Elongation in 8 in. [200 mm] min, %A | Elongation in 2 in. [50 mm] min, %A |
|---|---|---|---|---|
| Grade A | 75–95 [515–655] | 45 [310] | 15 | 19 |
| Grade B | 80–100 [550–690] | 50 [345] | 15 | 18 |
| Grade C | 80–100 [550–690] | 50 [345] | 17 | 20 |
| Grade D | 80–100 [550–690] | 50 [345] | 17 | 20 |