Properties and heat treatment process of American standard SA302 GrC steel plate

SA302 GrC steel plate is a manganese-molybdenum-nickel alloy steel plate for pressure vessels, which is often used in the production of reactors, heat exchangers, separators, EO reactors, heads and other equipment in the petroleum, chemical, power station, boiler and other industries. SA302 series steel plate is divided into four grades, namely SA302 GrA, SA302 GrB, SA302 GrC, SA302 GrD. Different grades of raw materials can be selected according to different usage requirements.

Delivery status of SA302 GrC steel plate: hot rolled, normalized, normalized + stress relief treatment.

Chemical composition of SA302 GrC steel sheet (melting analysis %)
C:≤0.25, Mn: 1.15-1.50, P: ≤0.025, S:≤0.025, Si: 0.15-0.40, Mo: 0.45-0.60, Ni: 0.40-0.70

Mechanical properties of SA302 GrC steel sheet:
Tensile strength: 550-690
Yield strength: ≥500
Elongation, gauge length 200mm, %: ≥17
Elongation, gauge length 50mm, %: ≥20

Heat treatment process of SA302 GrC steel plate: when the thickness is less than 50mm thick, hot rolling, normalizing, normalizing + stress relief treatment can be selected. When the thickness is greater than 50mm thick, the delivery state is normalized. When normalizing steel plates with a thickness greater than or equal to 100mm, the cooling can be accelerated by means of blower or liquid quenching followed by tempering in the temperature range of 1100-1300°F (595-705).