400*600 C250, standard manhole size, and change the round manhole cover, but the commonly used type is still 600MM. The company's product standards may vary according to the customer, with heavy-duty 400, standard 250, light 125, square manhole covers available in 500*500 B125. The thickness of the manhole covers varies depending on the material, generally ranging from 75-95mm.

Cover plates, regardless of size standards, are a type of ductile iron product. Firstly, they particularly enhance plasticity and toughness. Generally, well covers are made of various materials, and typically, with a diameter of 600MM and well wall thickness of around 13mm or more.