Dump semi-trailer is suitable for the transportation of bulk cargo such as coal, ore, building materials and so on. Dump semi-trailers can be divided into two categories according to their purposes: one type of heavy-duty and super-heavy dump trailers for off-road transportation are mainly responsible for large-scale mining, engineering and other transportation tasks, and they are usually used in conjunction with excavators. The other type of light and medium-sized ordinary dump trailers used for road transportation are mainly responsible for the transportation of loose goods such as sand, soil, and coal, and are usually used in conjunction with loaders.