GB/T 6728 Square and Rectangular Steel Pipe Standard
GB/T 6728 is a Chinese national standard applicable to the technical specifications of cold-formed electric-welded square and rectangular steel pipes, defining the production process, mechanical properties, and dimensional specifications of steel pipes.
1. Characteristics of GB/T 6728 steel pipes
● Diverse cross-sectional shapes: GB/T 6728 standard covers square and rectangular steel pipes, which can meet the needs of different application scenarios.
● Production process: Cold forming and electric welding processes are adopted, the steel pipe surface is smooth and the weld is stable, ensuring the mechanical properties and durability of the product.
● Excellent mechanical properties: It has good bending and compression resistance and is suitable for bearing different loads.
● High dimensional accuracy: GB/T 6728 steel pipes strictly control dimensional deviations in production and provide precise specifications to meet installation and application requirements.
2. Technical requirements of GB/T 6728 steel pipes
Item | Detailed description |
Material | Carbon structural steel and low alloy structural steel such as Q195, Q235, Q345 |
Cross-section shape | Square, rectangular |
Dimension range | Wall thickness: 0.5mm - 20mm, side length: 10mm - 400mm |
Tolerance | Cross-sectional dimensions, wall thickness, length, etc. meet the specified deviation range |
Tensile strength | Depending on the material, generally 330 - 520 MPa |
Yield strength | Depending on the material, for example, the yield strength of Q235 is ≥235 MPa |
Elongation | Elongation is 15% - 25% for different materials |
Welding process | Resistance welding or arc welding, the weld is flat and has no obvious defects |
Surface quality | Smooth surface, no cracks, bubbles, peeling and other defects |
3. Example of specifications of GB/T 6728 steel pipes
Cross-sectional dimensions (mm) | Wall thickness (mm) | Theoretical weight (kg/m) | Common materials | Typical applications |
40 x 40 | 2 | 2.31 | Q235 | Building structures, railings |
50 x 50 | 3 | 4.44 | Q345 | Machinery manufacturing, equipment supports |
100 x 50 | 4 | 7.85 | Q195 | Vehicle chassis, logistics equipment |
200 x 100 | 6 | 17.7 | Q235 | Bridge supports, heavy machinery structures |
When choosing suitable steel pipes, users can compare specifications, materials, etc. according to project requirements to ensure the stability and durability of the products. Yangtze Steel provides high-quality square and rectangular steel pipes that meet the GB/T 6728 standard to meet customers' diverse engineering needs and ensure the successful implementation of the project.
