How to calculate the strength of the jaw crusher’s eccentric shaft

Product Description

Jaw crusher’s eccentric shaft needs to bear large force in the work, so the eccentric shaft should have high strength. So how to calculate the strength of the jaw crusher’s eccentric shaft in order to know whether it can meet the requirement of the production? I will explain it in the following parts.

1. Draw out the axis’ calculation diagram. In the crushing, the crushing force is passed to the eccentric shaft by the movable jaw plate. Other parts of the shaft play small roles in this process. When calculate the force, they can be neglect, and only consider the crushing force. The crushing force is evenly distributed on the two movable jaw bearings, and we use F1 and F2 to represent them. The racks id equivalent two bearings which have reaction force to the eccentric shaft, and we use R1 and R2 to represent them. The distance between the point of the bearing frame and the point of the movable jaw bearing is represented by L.

2. Draw out the bending and torque distance diagram of the axis. The eccentric shaft does not bear fore in the vertical direction, so it only has horizontal bending moment. The torque born on the eccentric shaft is passed to the motor. Then this torque and the torque produced by the belt pulley, flying pulley and the crushing force must balance. Draw out the bending moment according to the positions produced by the torque.

3. Check the strength of the shaft. When check the strength of the shaft, you can only check the strength of the biggest moment, and that is the movable jaw plate’s bearing. If it is smaller than the stress of the eccentric shaft, then the strength of the jaw crusher’s eccentric shaft can meet the requirement, and Not vice versa.