The trailer suspension system is divided into double-axle or tri-axle leaf spring suspension.
It is to support load and absorb driving vibration.
The leaf spring is fastened on the axle body with U-bolt, and its two ends are blocked in the frame support.
The leaf spring on the medium support is connected by oscillating balance beam to bear the weight from vertical direction.
The horizontal acting force is transferred through the support, the connecting rod, the pull rod and the bracket on the axle.
When the semi-trailer goes through rough road, the balance beam swings along with the axle, and thus the load on every axle is balanced.
According to the height of the bearing surface, the suspensions can be installed with the leaf springs above or below the axles.