1. There should be an ideal speed change process in setting injection parameters, mold opening and closing stroke, mold protection pressure and so on to ensure the safe operation of the mold. 2. First, set the low-pressure protection pressure to 0, then set the injection molding machine to low-pressure manual, and repeatedly close the mold to see the actual position where the mold needs to be set with low pressure. The minimum low-pressure pressure is increased by 1% each time until the low-pressure mold locks to high pressure, which is the low-pressure protection pressure we want to set.