1 2 inch air release valve1 2 inch air release valve

Inspection well covers are an organic part of urban roads. In the process of urbanization, road construction is an important standard to test its results. Both for foreign visitors and local residents. “The missing manhole cover" is a shadow, which will not only bring inconvenience to travel, but also cause falling accidents, which will seriously bring property damage and personal casualties. It can be seen that in the process of urban construction, how to design and use manhole covers should become an important topic. China's inspection of manhole covers has roughly experienced three stages, the first stage from the mid-1990s. Before this, most of the inspection well covers were reinforced concrete type, with different sizes; Because the power pipeline is not buried deeply, no manhole cover is used. In the mid-1990s, a number of reinforced concrete manhole covers were replaced with steel manhole covers. However, this batch of manhole covers are easy to rust and fall off in a humid environment. The second stage is the end of the 1990s, China began to develop the standard of manhole covers, and began to promote the use of round cast iron manhole covers, and the shaft of the inspection well was transformed accordingly. Due to the good corrosion resistance of cast iron materials, a unified standard specification has been formulated. Therefore, a considerable part of this batch of inspection well covers is still in use. The third stage is that after 2008, with the emergence of new materials and new installation technology, the types of new manhole covers mainly include FRP manhole covers, steel fiber manhole covers and composite manhole covers, etc. These manhole covers have better anti-corrosion and anti-theft effects than cast iron material types, and the sound of human trampling or car rolling is smaller. Application trend of cast iron manhole cover Cast iron inspection well covers have a good effect on corrosion resistance, and many manhole covers are still good after a long time of use. Therefore, it is widely used. Some manufacturers are considering adding rubber rings to cast iron manhole covers to reduce their noise. There are also manufacturers to improve its locking in order to solve the problem of insufficient anti-theft function. Although the inspection of well covers may seem less important in urban advice and management. However, it is an important infrastructure in urban management, which is indispensable to the beauty of the city, the safety of citizens and the protection of pipelines. For urban planning and management, it is necessary to constantly use new materials and new technologies to inspect well covers and strengthen management. At the same time, it can encourage the "artistic" treatment of manhole covers, so as to add a bright color to the safety, convenience and beauty of the city. Key words: urban construction, road management, check well cover, urban life