The rotor of the motor YLV400-2-4 has pouring successful in Wannan mould workshop.During the producing of the motor with low-voltage high-power, the process of cast aluminium for rotor is always the weakness. We used to adpot centrifugal cast aluminium for the casting aluminium rotor, the method should trough plate in,sand filling,press fitting,preheating,pouring and so on,energy consumption and inefficiency. After discussions and meeting confirmed, cast aluminium workshop suggest that we could change the centrifugal pressure casting to pressure casting. Cooperate with technical and mould department, we have succed the first time. The pouring success of pressure casting for YLV rotor has thoroughly solved the bottleneck that occured in manufacturing, of rotor, it ensure the low-voltage high power motor delivery on time.