When people talk about round manhole covers, they will definitely discuss the particularity of the round shape. Because it can be rolled, it is convenient for workers to carry. And the round manhole cover does not have the problem of the longest diagonal. Its diameter is the same in any direction, and the manhole cover will not fall into the manhole, which is very safe. This is indeed the advantage and advantage of the round manhole cover. The round manhole covers are so good, Why not make all the manhole covers round? We can see square manhole covers everywhere in our lives. Why is this? Read More