GNEE GROUP

What is the Difference between SA 283 GR C and SA 516 GR 70?

ASME SA 283 GR C and SA 516 GR 70 are both carbon steel plates used in structural and pressure vessel applications, but they differ significantly in strength, heat treatment, and intended use. SA 283 GR C is a low-carbon steel with moderate strength for general structural purposes, while SA 516 GR 70 is a normalized steel with higher tensile strength for pressure vessels operating at moderate and lower temperatures.

Chemical Composition Comparison

The chemical compositions reflect their purposes: SA 283 GR C has lower carbon for better weldability, while SA 516 GR 70 includes manganese for toughness. Below is a table of typical compositions (in weight %, maximum unless specified):

Mechanical Properties and Testing

SA 283 GR C offers a minimum yield of 30 ksi (205 MPa) and tensile of 55-75 ksi (380-515 MPa), with good ductility but no impact testing requirement. SA 516 GR 70 provides higher yield of 38 ksi (260 MPa) and tensile of 70-90 ksi (485-620 MPa), with mandatory Charpy V-notch testing for low-temperature service.

Applications and Interchangeability

SA 283 GR C is used in low-pressure tanks and general structures, while SA 516 GR 70 excels in boilers and high-pressure vessels due to its normalization for better toughness. They are not interchangeable in high-pressure scenarios.