ASTM A181 – Carbon Steel Forgings, for General-Purpose Piping
Grade: Class60 and Class70
Chemical Requirements max,%
| Elements | Classes 60 and 70 |
| Carbon | 0.35 |
| Manganese | 1.10A |
| Phosphorus | 0.05 |
| Silicon | 0.10-0.35 |
| Sulfur | 0.050 |
A Manganese may be increased to 1.35 % max provided the carbon is reduced 0.01 % for each 0.06 % increase in manganese over the limit shown in the table.
Tensile Requirements
| Class 60 | Class 70 | |
| Tensile strength, min, ksi [MPa] | 60 [415] | 70 [485] |
| Yield strength,A min, ksi [MPa] | 30 [205] | 36 [250] |
| Elongation in 2 in. [50 mm], min, % | 22 | 18 |
| Reduction of area, min, % | 35 | 24 |
A Determined by either the 0.2 % offset method or the 0.5 % extension-underload method.