1. What is shot-to-shot specific pressure and how to adjust it?

    Answer: The shot pressure is the pressure per unit area of the metal liquid in the pressure chamber. On the premise of ensuring product quality, use a lower specific pressure as much as possible. The specific pressure of lighting die casting is generally less than 50MPA. The larger the product wall thickness, the higher the specific pressure requirement. The more complex the product structure, the higher the specific pressure requirements.

2. What is shot speed and how to adjust shot speed?

    Answer: The injection speed refers to the speed of the injection head during die casting. It is divided into slow injection speed and fast injection speed. Generally speaking, the injection speed refers to the fast injection speed. The size of the slow shot speed is that when the shot head passes through the sprue, it is better not to splash the metal liquid, generally 0.1 ~ 0.5M / S, and the fast shot speed aluminum alloy is generally 0.1 ~ 1.1M / S. The thinner the wall thickness of the casting, the faster the injection speed, the more complex the shape of the casting, the faster the injection speed, the larger the projection surface of the casting, the faster the injection speed, and the longer the casting ball path, the faster the injection speed.

3． What is the pouring temperature and how do I choose a pouring temperature?

    Answer: The pouring temperature generally refers to the average temperature of the molten metal poured into the injection chamber and filling the cavity. Generally, the lowest possible temperature is used while ensuring the molding and the required surface quality. The casting temperature of aluminum alloy is 650 ℃ ～ 720 ℃, the casting alloy has good fluidity, and the casting temperature can be lower; the casting temperature of thin-walled and complicated castings can be higher; the mold is large, the heat dissipation is fast, and the casting temperature can be high some.

4． What is the mold temperature, and what is the mold temperature during normal production of aluminum alloy die-casting molds?

    Answer: The mold temperature is the temperature of the mold during the production process. The temperature of the aluminum alloy die-casting mold during normal production is: 200 ° C to 280 ° C. Generally, the thinner the casting, the more complicated the structure, and the higher the mold temperature requirements.

5． What is the filling time? How to choose the filling time?

    Answer: The time required for the metal liquid to start to fill the cavity is called the filling time. Filling time of aluminum alloy die-casting: 0.01S ~ 0.1S. The principle of selecting the filling time is: (1) the alloy pouring temperature is high, the filling time should be longer; (2) the mold temperature is high, the filling time is longer; (3) if the thick wall part is far away from the inner gate, the filling is The time should be longer; (4) For alloys with high melting heat, the filling time should be longer; (5) When the exhaust effect is poor, the filling time should be longer.

6. What is holding time? What is the role of holding pressure? How to choose holding time?

    Answer: The holding pressure time is also called the holding pressure time, which is the time required for the solidification under the action of pressurized specific pressure after the metal liquid fills the cavity. The role of holding pressure is to crystallize the solidifying metal under pressure, so as to obtain a casting with a dense internal structure. The holding time of die-casting aluminum is 1 to 2 seconds when the wall thickness of the casting is less than 2.5MM, and 3 to 8 seconds when the wall thickness of the casting is 2.5 to 6MM. The selection principles are: (1) the crystallization temperature range of the die-casting alloy is higher, and the holding time is longer; (2) the wall thickness of the casting is large, and the holding time can be longer; Longer, the thicker holding time of the gate should be longer.

7. What is retention time? How to choose the retention time?

    Answer: The retention time is also called the cold mold time, which is the residence time of the casting in the die. That is, the time required from the start of holding pressure to the time when the casting is ejected from the mold. Sufficient retention time ensures that the casting is fully solidified in the model, cooled and has a certain strength. Usually the shortest time to make the castings not deformed and cracked is appropriate. Die casting aluminum alloy castings have a retention time of 5S ~ 30S, which has a direct relationship with the wall thickness of the casting. The thicker the casting wall thickness, the longer the retention time.