A516Gr70 steel vs Q345R steel

SA516Gr70 steel plate is a carbon steel plate for medium and low temperature pressure vessels, the implementation standard: ASTM A516 standard. Q345R steel belongs to the Chinese boiler and pressure vessel steel grade. The implementation standard: GB713-2014.

Steel manufacturing

A516Gr70 steelmaking process is killed steel, and should meet the requirements of A20 / A20M standard fine austenite grain size. The thickness less than or equal to 40mm is usually delivered in a hot-rolled state, and steel plates greater than 40mm must be normalized. Unless otherwise specified by the purchaser, when a notch toughness test is required for a steel plate with a thickness of 40 mm or less, the steel plate should be normalized.
Q345R steelmaking process is smelted by oxygen converter or electric furnace, and should be refined outside the furnace, usually delivered in hot rolling, controlled rolling, normalizing state.
A516Gr70 and Q345

Steel chemical composition analysis

By comparing A516Gr70, the material manufacturing and delivery status are stricter.
Comparison of chemical composition between A516Gr70 and Q345R (mass fraction) /%
A516Gr70 melting analysis requirements:
Carbon (plate thickness less than or equal to 12.5mm) content ≤0.27%
Carbon (plate thickness between 12.5mm -50mm) content ≤0.28%
Carbon (thickness between 50mm and 100mm) ≤0.30%
Carbon (thickness greater than 100mm) content ≤0.31%
Manganese content 0.85-1.20
Phosphorus content ≤0.025%
Sulfur content ≤0.025%
Silicon content 0.15--0.40
Note: For each decrease of 0.01% below the specified maximum carbon content, the upper limit of the specified maximum manganese content can be increased by 0.06%, the maximum allowable smelting analysis is 1.5%, and the maximum allowable product analysis is 1.6%.
 
Comparing the tensile properties of A516Gr70 and Q345R, it can be seen that Q345R steel is higher than A516Gr70, but A516Gr70 has a lower Charpy impact temperature. It shows that A516Gr70 can be used in minus 46 degrees environment, but Q345R can’t be used.
 

Pre: What are the differences between Q345B and Q345R steel?

Next: What is the steel Q345qE?