traffic trench drain grate

Bearing bar and cross bar:   1.According to the arrange pitch of bearing flat bar,gratings can be classified into several series.     1)20mm   2)30mm    3)40mm   2.According to the pitch of cross bar,it can be classified into 2 series   1)50mm  2)100mm                                    cross bar-1                                            cross bar-2                        cross bar-3                                             cross bar-4                        cross bar-5                                               cross bar-6