The difference between CMC and CMC;

1, with different functions: pits are generally used to store food and articles. Manholes are used in bends, branches, drops and other places of drainage pipelines, which is convenient for inspection and dredging of used wells.

2. Different locations: pits usually refer to cellars, which means basements. The manhole is a sewer manhole in the middle of the road, also called skylight.

There will be many underground pipelines in the construction of manhole cover cities, such as sewers, underground gas pipelines, tap water pipelines, power pipelines, communication pipelines and national defense pipelines. These pipes should have an outlet to the ground at regular intervals. The section from the pipeline to the ground is called manhole, and the manhole is generally flush with the ground, so a cover is needed to cover the manhole cover. Well covers are usually made of reinforced cement, metal, reinforced plastic and other materials, and their shapes are mainly round and square. Generally, the purpose of underground pipeline, storage unit, telephone number and other information should be indicated on the manhole cover.