标准说明 |
This specification covers carbon steel castings for general applications. The grades of steels covered here are: Grade N-1, Grade N-2, Grade U-60-30 [415-205], Grade 60-30 [415-205], Grade 65-35 [450-240], Grade 70-36 [485-250] and Grade 70-40 [485-275]. Except for Grades N-1 and U-60-30, all steel castings shall be heat-treated by full annealing, normalizing, normalizing and tempering, or quenching and tempering. Heat treatments shall be performed after castings have been allowed to cool. Heat and product analyses shall be performed wherein specimens shall conform to required chemical composition of carbon, manganese, silicon, sulfur and phosphorus. Except for Grades N-1 and N-2, all steels shall undergo tension test, and shall conform to the following mechanical requirements: tensile strength, yield point, elongation, and reduction of area. |