What is the main Chinese delivery standard for H-beams?

The primary Chinese standard is GB/T 11263-2017 "Hot-rolled H-section steel". It specifies technical requirements for dimensions, shape, weight, chemical composition (e.g., C≤0.22% for Q235B), mechanical properties (tensile strength, elongation), and inspection methods (ultrasonic testing for internal defects). For low-temperature environments, GB/T 11263 also includes grades like Q355ND with impact toughness requirements at -40℃. Delivery conditions often include "hot-rolled, as-delivered" or "normalized" for improved toughness.