Marking Method: The grade of steel is composed of three parts: the Chinese Pinyin letters representing the yield strength, the yield strength value, and the quality grade symbol. For example: Q345B, where:

Q—the initial letter of the pinyin for the Chinese character "屈" in "屈服 strength" of steel.

345 — Yield strength value, unit MPa

B—Grade B quality.

When the buyer requires the steel plate to have thickness direction properties, a symbol representing the thickness direction (Z-direction) property grade is added after the specified grade number, e.g., Q345BZ15.

Compliance Standard: Conforms to GB/T1591-2008.