15W4 Steel Grating Specifications (US & China Standard)
15W4 steel grating is a widely specified welded bar grating standard in industrial flooring systems. It provides tighter bearing bar spacing than 19W4, offering improved load distribution and enhanced safety performance.
As a professional Steel Grating manufacturer, we supply 15W4 grating according to both ASTM (US standard) and Chinese GB/YB standards to support international and domestic projects.
1. What Does 15W4 Mean? (ASTM Standard Explanation)
Steel Bar Grating designated as 15W4 follows the North American standard format:
- 15 = 15/16 inch bearing bar spacing (≈ 23.8 mm center-to-center)
- W = Welded steel grating
- 4 = 4 inch cross bar spacing (≈ 100 mm)
This configuration provides tighter spacing compared to 19W4, resulting in increased load distribution and improved walking safety.
2. China Standard Equivalent
Under Chinese standards such as YB/T 4001.1 and GB specifications, 15W4 typically corresponds to:
- Bearing bar spacing: 25 mm (常见型号 G255/30/100 或类似规格)
- Cross bar spacing: 100 mm
- Material grade: Q235 carbon steel (or equivalent)
- Surface treatment: Hot-dip galvanizing according to GB/T 13912
While the spacing may slightly differ (23.8 mm vs 25 mm), both standards are functionally equivalent for most industrial applications.
3. Technical Specifications
- Common bearing bar heights: 25 mm, 30 mm, 32 mm, 40 mm
- Common thickness: 3 mm, 5 mm
- Material density: 7.85 g/cm³ (carbon steel)
- Optional serrated surface for anti-slip performance
For higher structural demands, Heavy Duty Steel Grating versions are available with thicker and deeper bearing bars.
4. Surface Treatment Options
For corrosion protection, Galvanized Steel Grating is most commonly specified. Hot-dip galvanizing adds long-term rust resistance and extends service life in outdoor environments.
Stainless steel alternatives are also available for highly corrosive or marine environments.
5. Typical Applications
- Industrial platforms
- Equipment access floors
- Drainage trench covers
- Power plants and wastewater facilities
- Infrastructure and steel structures
Conclusion
15W4 steel grating under ASTM standards and its Chinese equivalent specifications provide enhanced load distribution and reliable structural performance. Understanding both standards ensures accurate project specification and international compatibility.
Contact our engineering team for detailed load tables, weight calculations, and customized fabrication services.
