Hydraulic system with protection device

The utility model discloses a hydraulic system with a protection device, which comprises a bottom plate, a loading plate is fixedly mounted at the upper end of the bottom plate, a support frame is fixedly welded at the upper end of the bottom plate, a top plate is fixedly welded at the upper end of the support frame, and a hydraulic cylinder is fixedly mounted at the lower end of the top plate. A gearbox is arranged at the output end of the hydraulic cylinder, a drill bit is fixedly installed at the lower end of the gearbox, and a limiting assembly is fixedly installed between the lower end of the top plate and the top of the gearbox. During use, the limiting assembly is arranged between the top plate and the gearbox, when the hydraulic cylinder located between the top plate and the gearbox is out of control, the limiting assembly can prevent the hydraulic cylinder from moving upwards or downwards excessively, and therefore the hydraulic cylinder can be protected to a certain extent; and damage to a workpiece