Rotor in squirrel-cage induction motor has direct effect on the motor performance. Vertical die casting process is one of the common techniques to produce industrial motors. The key to manufacture qualified industrial rotors smoothly depends on the casting cup and the precise temperature control in the process. A die casting melting cup without asbestos for vertical motor rotor production is designed. With this technology, no asbestos will be pressed and mixed into rotors. Meanwhile, using high pressure die casting equipment, the rotor quality can be improved effectively to satisfy the performance requirements of ultra high efficiency motor.