The heavy-duty trailer, low bed trailer is widely used and is mainly used for medium and long-distance freight heavy-duty transportation. Tandem leaf spring and suspension support, reasonable structure, strong rigidity, and strength, are used to support load cushioning. low bed trailers are usually used to transport heavy cargo (such as tractors, buses, special vehicles, etc.), rail vehicles, mining machines, forestry machines, agricultural machines (such as excavators, bulldozers, loaders, pavers, cranes, etc.) and other heavy-duty goods, the lower it's center of gravity, the better the stability and safety, and the stronger the ability to transport ultra-high goods and pass overhead obstacles. Low bed trailer structure and loading Low flat semi-trailer usually adopts a concave beam (or well type) frame, both the front section of the frame is a gooseneck (the towing pin of the front section of the gooseneck is connected to the traction saddle on the tractor, and the rear end of the gooseneck is connected to the semi-trailer frame), the middle section is the cargo platform (the lowest part of the frame), and the rear end is the wheel frame (including wheels). When loading machinery and equipment on a low-flat semi-trailer, it is usually loaded from the rear end of the semi-trailer, that is, by moving the mechanical equipment from the rear wheel frame or removing the wheels, and then fixing the mechanical equipment on the semi-trailer. The heavy-duty transport walking structure is made of high-strength international steel, which has lightweight and ensures its anti-twisting, anti-seismic, and anti-bump ability and meets the bearing capacity of different road surfaces.