Mould should be fully preheat homework before die casting production, its action is as follows:
1. Make mould achieve better thermal equilibrium, and the casting solidification velocity uniformity and pressure transmission.
2. Keep die-casting alloy filling when liquidity, good formability and improve the quality of the casting surface.
3. Reduce the pre-production, raise the productivity of die casting.
4. Lower mould hot alternating stress, improve the service life of the die.