Overview

H-shaped steel is an efficient and economical structural profile with an optimized cross-sectional area distribution and a good strength-to-weight ratio. It gets its name from the cross-section, which takes the shape of the letter “H.” Due to the right-angled arrangement of all parts, H-shaped steel can resist bending in all directions, hence promoting good construction and saving costs with reduced structural weight. Thus, it sees wide applications in many fields.

Applications of H-shaped Steel

H-shaped steel is extensively used in both industrial and civil engineering structures, including:

• Beam and column components for buildings
• Load-bearing supports for industrial structures
• Steel piles and supporting structures in underground projects
• Structural components in petrochemical and electric power industries
• Long-span steel bridge elements
• Frames in shipbuilding and machinery manufacturing
• Beam supports in trains, cars, and tractors
• Port conveyor belt supports and high-speed rail barriers

H-shaped steel is commonly employed in industries such as construction, bridge engineering, and oil drilling platforms due to its superior properties.

Types of H-shaped Steel

H-shaped steel is classified into two main types: hot-rolled and welded.

Hot-Rolled H-shaped Steel

Hot-rolled H-shaped steel is further divided into three categories:

1. HW (Wide-Flange H-shaped Steel): The height and flange width are approximately equal. It is primarily used as core columns in reinforced concrete frame structures.
2. HM (Medium-Flange H-Shaped Steel): The height-to-flange width ratio ranges from 1.33 to 1.75. It is used as steel frame columns and beams in structures subjected to dynamic loads, such as equipment platforms.
3. HN (Narrow-Flange H-Shaped Steel): The height-to-flange width ratio is 2 or more. It is mainly used for beams and serves functions similar to I-beams.

Common materials used for H-shaped steel include Q235B and Q355B.

Welded H-shaped Steel

Welded H-shaped steel is produced by assembling and welding steel plates using an automated H-shaped steel production line. The process involves the following steps:

1. Cutting:
   • Steel plates are leveled before cutting.
   • A flame multi-head straight strip cutting machine is used to cut multiple plates simultaneously to prevent side bending.
   • The steel plate’s material, specifications, and dimensions must be verified before cutting.
   • Rust, oil, and other debris must be removed to ensure cutting quality.
2. Assembly:
   • The centerline of the flange and positioning line of the web plate are marked.
   • Components are checked for accuracy before assembly.
   • The web and flange plates are first assembled into a T-shape before forming the H-shape.
   • Joints should be staggered by at least 200mm.
   • Positioning welding should be done by certified welders using the same materials as formal welding.
3. Welding:
   • Rust, burrs, oxides, and oil must be removed from the weld area before welding.
   • Arc starting and extinguishing plates must be added at both ends of the component.
   • Preheating (80-120°C) is required within 100mm of both sides of the weld.
   • The welding method uses portal-submerged arc welding.
   • Welding deformation is minimized by alternating welding sequences.
   • Weld height must conform to design specifications.
4. Correction:
   • Mechanical or flame correction is performed to ensure accuracy.
   • Flame correction is done at 800-900°C to prevent deformation.

Advantages of H-shaped Steel

1. High Structural Strength: Compared to I-beams, H-shaped steel has a higher section modulus, saving 10-15% of metal under the same load-bearing conditions.
2. Flexible Design: A steel structure with the same beam height allows for 50% larger bays than a concrete structure, enhancing design flexibility.
3. Lightweight: H-shaped steel structures are 15-20% lighter than traditional structures, reducing self-weight and lowering foundation costs.
4. High Stability: With excellent plasticity and resistance to seismic forces, H-shaped steel is ideal for earthquake-prone areas.
5. Increased Usable Space: Steel structure columns have smaller cross-sections than concrete, increasing effective building space by 4-6%.
6. Material and Labor Savings: Hot-rolled H-shaped steel reduces material consumption, labor, and residual stress while improving appearance and quality.
7. Environmental Benefits:
   • Dry construction minimizes noise and dust pollution.
   • Less soil disturbance during foundation work preserves the environment.
   • High recyclability of scrap steel reduces construction waste.
8. High Industrial Production Efficiency:
   • Facilitates mechanical manufacturing and mass production.
   • Ensures precision, ease of installation, and consistent quality.
9. Faster Construction:
   • Requires less space and is suitable for all-weather construction.
   • Steel structures can be built 2-3 times faster than concrete structures.
   • Accelerates project completion and reduces financial costs.

Conclusion

H-beam steel has been developed into a modern, efficient construction material that boasts superior mechanical properties, requires less weight, and offers cost-effective advantages. Its wide applicability in various industries-structural construction, road and bridge construction, and industrial manufacturing makes it an essential constituent in modern engineering. Its structural stability, flexibility, and environmental benefits further enhance its appeal as an optimal choice for modern infrastructure development.