Differences between American standard steel and domestic H-shaped steel

With the widespread application of American standard H-beam steel, domestic H-beam manufacturers can provide complete product specifications to meet various needs of different industries. The variety of domestic H-beam products needs to meet the corresponding steel standard requirements. Commonly used varieties include carbon structural steel and low alloy high-strength structural steel. Varieties with special functional requirements include: weather resistant structural steel, hot-rolled H-shaped steel with thickness directional performance, hot-rolled steel with improved welding performance, fire-resistant hot-rolled H-shaped steel, seismic hot-rolled H-shaped steel, and hot-rolled H-shaped steel for marine engineering structures. The cross-sectional specifications and characteristics of domestic H-beam products should comply with the requirements of relevant standards.

The selection of steel should follow the principles of technical reliability and economic rationality, taking into account the importance of the structure, load characteristics, structural form, stress characteristics, connection methods, working environment, steel thickness, and many other factors.

2.1 Steel used for H-beam and its properties

According to the requirements of the "Design Standard for Steel Structures" GB50017-2017, when H-shaped steel is used as a steel component, Q235, Q355, Q390, Q420, and Q460 steel can be selected. In terms of variety, products such as carbon cable steel, low alloy steel, weathering steel, fire-resistant steel, seismic steel, etc. can be selected. The chemical composition, performance requirements, and quality requirements of the products should comply with corresponding standards. The execution standards for American standard section steel are slightly different.

Q235 and Q355 steel are commonly used in practical engineering, as the former has moderate strength, good load-bearing capacity, weldability, and processability; The latter has higher strength and bearing capacity, and has good plasticity, toughness, and weldability, making it widely used in the construction field.

2.1.1 Carbon structural steel

When using carbon structural steel for H-shaped steel, its chemical composition and mechanical properties should comply with the current national standard "Carbon Structural Steel" GB/T700-1

2006 regulations. The product is divided into four categories based on its quality, namely A, B, C, and D. The deoxygenation methods are represented by the symbols F, Z, and TZ, respectively, for boiling steel, killed steel, and special killed steel. The structural steel should be killed steel. Products are generally delivered in hot rolled condition.