The JZ-460/660 (G7 semi-melting thermal field) polysilicon ingot casting furnace utilizes directional solidification technology, employing a vertical gradient directional crystallization process. Through precise temperature control via heaters, it effectively manages heat input and output, ensuring excellent product quality. It can operate at a lower temperature gradient, producing a 1200kg silicon ingot in approximately 85 hours. During the growth process, the movement of the temperature and insulation layer creates a vertical temperature gradient, enabling directional crystal growth. During the processes of charging and ingot extraction, only the lifting mechanism of the lower furnace chamber is used. The unit energy consumption of this furnace type is less than 6.5 kW·h/kg. Standard JZ-460/660 (G5, G6) furnace types can achieve the large charge capacity of the G7 furnace type simply by upgrading the thermal field.