Cast iron ladder: cast iron ladder, also known as cast iron step, is made of QT500-7 nodular cast iron, with pattern grooves on the surface and convex parts on the left and right, which is easy to be fixed to the inner wall of the inspection well, and also convenient for the inspection well inspectors to grasp and trample the anti-skid effect.
Because it is related to the safety of the upper and lower personnel, so the quality requirements are very high. Made according to national standard 97S501-1 and 14S501, stepping weight of nodular iron of 300 * 165mm is 2.9 kg, stepping weight of 250 * 165mm is 2.6 kg, so it is purchased and used as standard.