Pressure Vessel Plates, Carbon Steel, for Moderate and Lower-Temperature Service to ASTM A 516 A 516M Standard ASTM A 516 or ASME SA 516 grade is one of the most popular steel grades. It is primarily intended for use in welded pressure vessels where notch toughness is important.These grades cover a range of tensile strengths from 55 - 90 MPa and this versatility explains much of the specifications popularity. For plates thinner than 40mm normally supply as rolled. Plates above 40mm thick are normalised. For A 516 grade 70, which is one of most popular steels, the ASME standard composition is as follows (dependent on grade):