During working condition, jaw crusher will be overload mostly due to human factors. If the crusher is overload, it will be stopped or seriously the internal parts will be broken. Therefore, when the jaw crusher is overload, what can we do to protect the machine?

1. When the non-crushed materials enter into the machine, the crushing force is increased and the pressure acts on the working cylinder is higher than the thrusting force of the hydraulic cylinder, causing the oil pressure in the working chamber rise immediately that leads to the machine stopping. In this case, the throttle valve can be installed inside the crusher to make the hydraulic cylinder automatically discharged and limit the maximum thrusting force of the thrusting plate to protect the machine.

2. Remove the non-crushed materials in time. There are two ways to remove the materials. One is to shut down the machine and then remove the non-crushed materials from the crushing chamber artificially. The other way is to remove the materials automatically by machine self. Due to the limitation of thrusting force, the piston retracts on the right direction, correspondingly the discharging opening of jaw crusher is enlarged. At the same time, due to the meshing of movable jaw, the non-crushed materials move down and are discharged finally from the machine.