During operation, the pressure chamber is placed vertically, and the upper punch is above the pressure chamber, and the lower punch is located at the position where the nozzle orifice is blocked, to prevent molten metal from pouring into the pressure chamber and flowing into the nozzle hole by itself. The opening and closing movements of the mold move horizontally. After the mold is opened, the die casting remains in the movable mold.
 
The working steps of the cold chamber die casting machine are as follows:

1. Close the mold.

2. Pour molten metal into the press chamber manually or by other means.

3. The upper punch moves down at a lower injection speed and enters the pressure chamber until it just touches the molten metal surface.

4. When the upper punch is turned to a higher injection speed and pressed down, the lower punch and the upper punch will move down synchronously while maintaining the relative distance between the upper punch and the molten metal.

5. When the lower punch moves down to let out the nozzle orifice, it just descends to the nozzle part and is supported, therefore, the upper and lower punches squeeze the molten metal at high speed to the nozzle hole (part of the sprue) injection.

6. The molten metal is filled into the mold cavity from the inner gate through the sprue composed of the nozzle, the sprue sleeve, the tapered hole of the fixed mold, and the diverter. 

7. After the filling is completed, the upper punch can still maintain a certain pressure until the molten metal in the cavity is completely solidified into the die casting 1, and the molten metal in the runner and the pressure chamber solidifies into the direct gate and the remaining material respectively cake. 

8. The upper punch lifts and resets; at the same time, the lower punch moves upwards to cut away the remaining cake that is still connected to the straight gate. 

9. The lower punch continues to rise, lift the remaining cake out of the top surface of the pressure chamber, and then take it away manually or by other means.

10. Move the lower punch down and reset to block the nozzle orifice. 

11. Open the mold, the die-casting part and the straight gate remain on the movable mold together, and then eject and take out the die-casting part; once the remaining material cake is cut away, the mold opening action can be executed immediately, or it can be executed at an appropriate time, Has nothing to do with the movement of the lower punch to complete the lifting and resetting.