The AUTOPOWER Overload Pump is high quality!1. It is installed on the punch press to detect the excess hydraulic pressure inside the hydraulic cylinder of the slider. 2. When the overload situation occurs, the oil pressure can be quickly released within three thousandths of a second. 3. When overload occurs, the micro switch generates an electrical signal to notify the punch to stop the operation urgently to protect the punch and die. 4 After the overload occurs, the hydraulic pump is driven by air to quickly replenish the normal working pressure of the hydraulic cylinder, so that the punch can operate normally immediately. 5. There is a constant pressure control valve inside the overload protection device, which can automatically adjust the oil pressure, which can eliminate the influence of the pressure rise when the oil temperature rises during the punching process.