What is criteria to classify a grade of A514 steel plate? 1

[kingfrog]

1.Meaning of each grade
Even thoug the ASTM A514 code has many grades, mechanical proprties of each grades is same.
I guess the meaning of each grade is limitation of
thickness. Is it correct?

2.Maximum heat-resistance level
Our sub-vendor recommend grade E for rotating wheel because it has good heatproof properties to maintain tensile strength during operating high temperature like as over 400?.
Is it correct? If not, how much remain at over 400??

 

[metengr]

kingfrog;
The differences in Grades deal with variations in chemical composition that ultimately result in thickness limitations assuring through thickness mechanical properties, as you indicated in your post. Weldability of the above steels is also a consideration for their use and must be evaluated for each Grade.

ASTM A 514 is supplied in a quench and tempered condition, and use of "high temperature" is a relative term. You need to narrow down the application, including actual service temperature limitation.