The suspension is an important part of flat bed semi trailer connecting the chassis to the frame. The vehicleâ??s supporting force, braking force, driving force, etc. are all transmitted through the suspension system. It can also reduce the impact of bad roads on vehicles and ensure the stability of vehicles. Suspensions are generally divided into independent and non-independent suspensions. For semi-trailers, non-independent suspensions are used because of the need for strong carrying capacity. There are 3 kinds of common suspensions for flatbed container trailer: 1. Bogie suspension The bogie suspension is to reduce the common leaf spring front and rear brackets to a single bracket connected to the car body. Its load point is shared on the front and rear axles. Compared with ordinary leaf spring suspension, the bearing capacity of bogie suspension is bigger. This suspension is less commonly used on ordinary semi-trailers, mainly on heavy vehicles. This 2 axle flatbed trailer from TITAN uses bogie suspension. If you are interested in this trailer, you can click â??Bogie Suspension Flatbed Trailerâ?? to learn more. 2. Mechanical suspension The mechanical suspension is our common leaf spring. It is mainly composed of a leaf spring, suspension support (commonly known as lifting gear), connecting rod, U-bolt, and other parts. The longitudinal force of the body falls directly on an axle. The biggest advantage of this suspension is that it is cheap, reliable, and easy to maintain. At present, more than 80% of ordinary semi trailers use a leaf spring balanced suspension. 3. Airbag suspension The most obvious feature of an air suspension is its airbag-type air spring. The weight of the air spring itself is relatively light, the air medium friction in the airbag is small, there is almost no noise during operation, and its life is 2-3 times that of the leaf spring. However, when using an air spring, a rod system capable of transmitting various forces and moments other than the vertical force must be provided, so the suspension structure is complicated; in addition, the airbag spring has strict requirements on sealing and its cost is also high. At present, airbag suspension for semi-trailers is mostly in high-end fields such as precision instrument transportation and hazardous chemical transportation.