• High-quality steel——P≤0.035；S≤0.035；Cu≤0.3；Cr≤0.3；Ni≤0.3
• Extra-quality steel （Suffix A）——P≤0.025；S≤0.025；Cu≤0.25；Cr≤0.3；Ni≤0.3
• Special High-Quality Steel (Suffix E)——P≤0.025；S≤0.015；Cu≤0.25；Cr≤0.3；Ni≤0.3

• Cu is not more than 0.3% when smelting scrap steel

• The forgings must be inspected for mechanical properties after performance heat treatment and before any surface treatment.
• After the samples are removed, no heat treatments that affect the mechanical properties or any processing that influences the test results shall be conducted.
• Mechanical property testing primarily evaluates the material\'s tensile strength, impact resistance, and hardness. When conducting tensile, impact, and hardness tests simultaneously, the hardness value is for reference only. Alternatively, one may choose to perform only one of the tensile, impact, or hardness tests.