Composite Gully Grate for road drainage system

Specifications manhole cover

1 material:ductile iron 500/7

2 size:750*750*100 co:600

3 coat:Black bitumen painting

4 packing:pallet

Square/Round Cast Iron Manhole Cover      1.Technical standard: Table1

Item No.	Standard
Anti-compressive strength MPa	≥30
Anti-breaking strength(Mpa)	≥14
Impact toughness resistance (kg/cm2)	≥95
Freezing-thaw resistance, Anti- compressive strength losing rate %	≤13
Heat deterioration, Anti breaking strength relative change rate	≤0.4
Accelerated aging, Anti breaking strength relative change rate	≤3

   2.The opening between gully grating and seating Table2

Gully grating mm	Opening mm
Length≥500 & Width≥400	7±3
Length500&Width400	6±2

        Welcome to contact me if you have any questions. Thanks!