The Ductile iron manhole cover plate has uniform force, higher bearing level than the square manhole cover, and the circular manhole cover is not easy to tilt, which can better protect the safety of pedestrians and vehicles, and has the following specific advantages:
(1) The round manhole cover is less edges and corners, which is more beautiful in appearance than the square manhole cover.
(2) The round manhole cover is balanced and can prevent noise.
(3) The round manhole cover has uniform force, higher than the square manhole cover, and the round manhole cover is not easy to tilt, which can better protect the safety of pedestrians and vehicles.
(4) The round manhole cover has a better use performance than the square manhole cover. Street lamp manhole cover has vehicles and pedestrians passing by at any time, the round manhole cover through the diameter of each center is the same, so that no matter how the manhole cover is rolled, its diameter will be slightly wider than the manhole below, and the manhole cover will not fall into the wellmouth.The diagonal line of the square manhole cover is obviously longer than each side long. When the manhole cover is rolled up, it is easy to fall into the manhole along the diagonal direction of the wellmouth, causing safety risks.