Plain Steel Bar Grating
Flat-top bearing bar grating for industrial flooring, platforms, walkways, and drainage covers. The most widely specified form of steel grating worldwide.
Calculate weight for your spec
Enter bearing bar size, pitch, and panel dimensions to get exact kg/m² and order weight.
Specification Overview
Plain steel bar grating consists of bearing bars (flat steel strips running longitudinally) welded to cross bars at uniform intervals. The "plain" designation means the bearing bar tops are left flat — as opposed to serrated grating where the tops are notched for anti-slip performance.
| Parameter | Standard Range |
|---|---|
| Bearing bar height | 20 mm – 75 mm |
| Bearing bar thickness | 3 mm, 4 mm, 5 mm, 6 mm |
| Bearing bar pitch (c/c) | 11 / 15 / 22 / 30 / 34 / 40 / 60 mm |
| Cross bar type | Round (⌀5–10mm), twisted square (5–6mm), flat |
| Cross bar pitch | 25 / 50 / 76.2 / 100 mm |
| Panel width | Up to 1,200 mm (standard: 1,000 mm) |
| Panel length | Up to 6,100 mm (standard: 6,000 mm) |
| Weight range | 10 – 80 kg/m² depending on spec |
| Steel grade | Q235 / A36 / S235–S355 |
Most Common Specifications
| Bearing Bar | Pitch (mm) | Weight (kg/m²) | Typical Use |
|---|---|---|---|
| 25×5 mm | 30 | 37.1 | General industrial flooring — most popular globally |
| 25×5 mm | 22 | 48.2 | Heavy-duty floors, closer load distribution |
| 30×5 mm | 30 | 43.2 | Medium-heavy platforms |
| 40×5 mm | 30 | 57.1 | Long-span walkways, structural floors |
| 20×3 mm | 30 | 19.9 | Light-duty covers, architectural |
| 65×5 mm | 30 | 88.0 | Long-span, heavy industrial |
Cross bar: 6 mm round @ 50 mm pitch. For other configurations use the weight calculator.
Applicable Standards
Chinese national standard — used by virtually all Anping factories. Covers bearing bar, cross bar dimensions and tolerances.
North American standard. Designation codes (e.g. 19-W-4) describe bar height in 1/16", type (W=welded), and c/c pitch in 1/4".
UK/European standard. Defines load classes A–E and structural performance requirements. Commonly specified for UK construction projects.
Surface Finishes Available
- Black (mill finish) — oiled to prevent transit rust, must be painted or galvanized after installation in outdoor environments
- Hot-dip galvanized — ISO 1461 / ASTM A123, 45–85 μm zinc coating, 25–40 year service life outdoors
- Painted — primer + topcoat; less durable than galvanizing but lower initial cost
- Epoxy coated — for chemical environments; consult factory for specific chemical resistance
Why Source from Anping, Hebei?
Anping County produces over 70% of China's steel grating exports. The industrial cluster of 1,700+ factories enables competitive pricing, full specification flexibility, and short lead times (typically 15–25 days FOB). Most factories hold ISO 9001 certification and can provide mill certificates, test reports, and third-party inspection.
Frequently Asked Questions
What is plain steel bar grating?
Plain (smooth-top) steel bar grating has flat-top bearing bars welded to cross bars at regular intervals. It is the most common form used in industrial flooring, platforms, and walkways where slip resistance is not the primary concern.
What are standard bearing bar sizes for plain grating?
Common sizes range from 20×3mm to 75×6mm. The most popular global specification is 25×5mm with 30mm centre-to-centre pitch, which gives approximately 37 kg/m².
What is the difference between plain and serrated grating?
Plain grating has smooth flat-top bars. Serrated (notched) grating has teeth cut into the top edge of each bearing bar, providing better grip in wet or oily environments. Serrated grating weighs slightly less due to material removed.
Can plain steel grating be hot-dip galvanized?
Yes. Plain carbon steel grating is routinely hot-dip galvanized to ISO 1461 / ASTM A123. Galvanizing adds approximately 4% to the weight and provides 25–40 years of corrosion protection in outdoor environments.