What are the common specifications of well grates?

The common specifications of manhole grates need to be comprehensively considered in combination with size, load-bearing grade, material and applicable scenarios. The main classifications are as follows:

📏 ‌ I. Size specifications ‌

Common planar dimensions ‌ (length × width, in mm)

Single comb ‌ : 300×500, 400×500, 400×600, 500×500, 600×600;
Double grates ‌ : 400×800, 400×1000, 450×750, 450×1500;
Special CUSTOM ‌ : 200×500 (narrow slit drainage), 800×1000 (high flow area).

Thickness range ‌

Lightweight: 20-30mm (for sidewalks and green belts)
Heavy duty: 40-50mm (for motor vehicle lanes and squares).

Mesh/clearance standard ‌

Drainage grates: 5×5mm, 10×10mm (anti-clogging design);
Industrial coal grate: 30-50mm (to prevent large blocks from getting stuck).
⚖️ ‌ 2. Load-bearing grades and applicable scenarios ‌
Grade ‌ ‌ Load-bearing range ‌ ‌ Thickness ‌ ‌ Typical scenario ‌ ‌ Representative Specification ‌
Light ‌ ≤25 tons 20-30mm sidewalk, community green belt 300×500×20
Medium ‌ 25-40 ton 30-40mm slow lane, residential lane 400×600×30
Heavy duty ‌ ≥40 tons ≥40mm Fast lane, port, industrial area 450×750×40
Special type ‌ CUSTOMIZED load-bearing CUSTOMIZED mine coal unloading ditch, chemical plant flat steel 200-300mm high
🧱 ‌ III. Specification characteristics corresponding to material ‌

Ductile iron (QT500-7) ‌

Advantage ‌ : high strength, high pressure resistance (standard D400/C250 grade);
Common specifications ‌ : 450×750D400, 400×700B125.

Stainless steel/Composite ‌

Lightweight size ‌ : 300×300, 300×500 (lightweight, corrosion-resistant);
Special tree grating ‌ : 1220×3660mm (full fiberglass grating).
🏗️ ‌ 4. Customized specifications for special scenarios ‌
Series rainwater inlet ‌ : Double grates horizontally connected, size must match the series spacing (e.g. 450×1500mm pin connection);
Tree pit grate ‌ : 38×38×25mm grid unit, whole plate 1220×4000mm;
Mine coal grate ‌ : flat steel 10-20mm thick, hole 30-50mm (manganese steel).

💎 ‌ Selection suggestions ‌ : Heavy ductile iron grates (e.g. 450×750×40) are preferred for motor vehicle lanes, and lightweight composite grates (400×500×20) are preferred for sidewalks; In industrial scenarios, the mesh size needs to be customized according to the particle size of the materials.