Steel grade designations can look like a foreign language, but they follow predictable systems. Chinese grades such as Q235B use a yield-strength figure, while ASTM grades such as A36 refer to a standard specification rather than a strength value.
The practical difference matters most at the point of use: structural frames need guaranteed yield strength, pressure vessels need impact-tested plates, and architectural finishes need surface quality above all.
A reliable supplier should provide mill test certificates that state the chemical composition and mechanical properties for every heat number. If a quotation cannot be backed by a certificate, treat it as a red flag.
Before ordering, confirm the governing standard for your destination market, the required tolerances, and the surface finish. These three decisions determine both cost and compliance.