... , BS4592, AS1657, JS31011.3 Grating Dimension Load Bearing Flat Bar sizeThickness≥3mm, depth ≥19mm19X3,19X5,20X3, 20X5 ... 40X6, 40X8, 40X10,….90X6….Pitch of Load bearding flat bars(mm)12.5,15, 20, 30, 30 ... -theft)2.1 Normal type of Drainage/Ditch Cover Embedded installation, safe and reliable, anti-thrust ... part. 2.3 Security type of Drainage/Ditch Cover Both ends connected with steel frame through gemel ...