(1) After the metal enters the cavity, it should be designed for the first impact position, so that it can be exhausted and the forward flow of smelting liquid should be stored. The side gate is selected for the die-casting pot, so the overflow groove should be set at the far end opposite the inner gate. At the same time, considering that the liquid flow will flow back after impact, an overflow groove is also set near the two sides of the runner.

(2) The wall of the die-casting pot is relatively thin. Therefore, the temperature of the general mold during production is not too high, and it is easy to produce cold partitions and patterns. Therefore, in this defect, more overflow grooves can be set to meet the needs of heat balance. .

(3) In vacuum die-casting, a large-capacity stepped overflow tank with cooling water is generally used, which is the starting point for vacuuming and drawing out the gas, and it can also absorb cold contaminated metal.

(4) The choice of stepped overflow groove in the vacuum die-casting pot is mainly to consider the use of exhaust. If it is used for thermal balance, generally rectangular trapezoidal blocks can be used.