When the leaf spring is installed in the vehicle suspension and the vertical load it bears is positive, each spring piece is forced to deform and has a tendency to arch upward. At this time, the axle and frame are close to each other. When the axle and frame are far away from each other, the positive vertical load and deformation of the leaf spring will gradually decrease, sometimes even reverse.

The main lug is under severe stress, which is the weak point. In order to improve the stress of the main lug, the end of the second piece is often bent into a lug and wrapped outside the main lug, which is called the lug. In order to make it possible for each piece to slide relatively during elastic deformation, there is a large gap between the main piece lug and the second piece lug. In some suspensions, the two ends of the leaf spring are not made into rolling ears, and other support connection methods are used, such as rubber support pads.

The flat rectangular steel plate is curved, and the spring is used for the chassis made of several pieces. One end is installed on the hanger with a pin, and the other end is connected to the girder with a lifting lug to make the spring retractable. It is applicable to medium and large cargo trucks.

Automobile leaf spring is very important. As we all know, leaf spring is composed of many steel plates with elasticity, consistent width and thickness, and different length. Its function is to connect the frame and axle with suspension, and expose it between the frame and axle, bear the load impact of the wheel on the frame, reduce the severe vibration of the body, and maintain the stability of the vehicle and its adaptability to different road conditions.