Dump semi-trailers can be primarily classified based on their unloading method and load-carrying capacity.
Categorized by unloading method, the legal dump semi-trailers available on the market fall into three main types: side-dump, standard rear-dump, and flatbed rear-dump. Side-dump trailers are often subject to site-specific limitations regarding unloading operations. Standard rear-dump trailers typically feature a cargo box height of no more than 0.6 meters and a relatively small cargo capacity. Flatbed rear-dump trailers face the risk of regulatory scrutiny regarding unauthorized modifications. Additionally, there are container dump semi-trailers, which consist primarily of a container semi-trailer chassis equipped with a hydraulic lifting mechanism.
Categorized by load-carrying capacity, they are divided into lightweight models designed for standard-load transport and heavy-duty models (such as the "Hundred-Ton King"). The curb weight of a lightweight dump semi-trailer combined with its tractor unit generally does not exceed 20 tons, allowing for a net cargo capacity of nearly 30 tons under current regulations governing vehicle weight limits. The heavy-duty dump semi-trailers referred to as "Hundred-Ton Kings" belong to the latter category.
