The squirrel-cage rotor plays a critical role in motor performance. Vertical die-casting is a common production process for industrial motors. The traditional vertical die-casting technique adopts a boosting method to achieve a certain injection ratio pressure, and the injection system is often operated in an ultra-high-pressure state. It is likely to cause failures in production. What’s more, the lagging of pressurization has limited help in quality improvement, and the rotor filling rate is low. The high pressure ratio die-casting process increases the area ratio of the injection cylinder to the die-cast melting cup, using the medium energy accumulator to achieve one-time high pressure ratio die-casting. The equipment works stably and is not prone to failure. Compared with the traditional technique, the quality of the produced rotor is significantly improved, and the filling rate is increased by 3%~5%, which greatly improves the overall performance of the motor.