Hebei manhole covers are essential for urban construction. The analysis of manhole covers can be divided into closures at the top of entrances and exits of underground facilities. Especially in recent years, the state has increased its investment in infrastructure and the development of urbanization, and the state has invested heavily in public facilities. Fire prevention, sanitation and other public facilities need to install inspection wells and manhole covers. The urban reconstruction and the construction of new electric wires, cables, and optical cables are changed to open-air underground, so the demand for manhole covers has increased greatly. Rainwater rafters are used as drainage ditch covers, and are widely used in urban roads, squares, and around residential areas. The materials used for inspection of manhole covers were mostly mostly made of reinforced concrete. Due to their defects such as brittleness, aging, and fracture, they were gradually replaced by cast iron and ductile iron. Now cast iron (including nodular cast iron) manhole covers account for more than 80%, especially compared with cast iron manhole covers, nodular cast iron manhole covers have improved in brittleness, rust, and load capacity, so the amount of use is increasing. Bigger. Because cast iron manhole covers have recycling value, some criminals are profitable. The cast iron manhole covers have been stolen and smashed and bought to waste recycling shops. Especially in recent years, with the rise in steel prices, the manhole cover has become increasingly serious. In recent years, with the country ’s increased investment in infrastructure and the development of urbanization, the state has invested heavily in public facilities. It is estimated that the number of new manhole covers and annual replacements in the country is at least 10,000 units per year. It can be seen that the demand for manhole covers is huge.