one What is injection pressure and how to adjust injection pressure?

Answer: The injection specific pressure is the pressure of liquid metal in the pressure chamber per unit area. Under the premise of ensuring product quality, try to use a lower specific pressure. The specific pressure of lamp die casting is generally less than 50MPA. The greater the wall thickness of the product, the higher the specific pressure requirements. The more complex the product structure, the higher the specific pressure requirements.

two What is the injection speed and how to adjust it?

Answer: The injection speed refers to the speed at which the injection head moves during die casting, including slow injection speed and fast injection speed. Generally speaking, the injection speed refers to fast injection speed. The slow injection speed is better to avoid splashing of molten metal when the injection head passes through the pouring mouth, which is generally 0.1~0.5M/s. The fast injection speed of aluminum alloy is generally 0.1~1.1M/s. The thinner the casting wall thickness is, the faster the injection speed is required. The more complex the casting shape is, the faster the injection speed is required. The larger the casting projection surface is, the faster the injection speed is required. The longer the casting ballast path is, the faster the injection speed is required.

three What is pouring temperature and how to select pouring temperature?

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

four What is the mold temperature? What is the mold temperature of aluminum alloy die-casting die during normal production?

Answer: The mold temperature is the mold temperature in the production process. The temperature of aluminum alloy die casting mold in normal production is 200 ℃~280 ℃. Generally, the thinner the casting, the more complex the structure, and the higher the mold temperature requirements.

five ．   What is filling time? How to select filling time?

Answer: The time required for the metal liquid to start injecting into the cavity and fill is called filling time. The filling time of aluminum alloy die-casting is 0.01S~0.1S. The selection principle of filling time is: (1) If the pouring temperature of alloy is high, the filling time should be longer; (2) If the mold temperature is high, the filling time will be longer; (3) If the thick wall part is far from the inner gate, the filling 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.

six What is holding time ? What is the function of pressure holding ? How to select pressure holding time ?

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

seven What is retention time? How to select retention time?

Answer: Mold retention time is also called cold mold time, which is the retention time of castings in the die. It refers to the time required from holding pressure to casting ejection. Sufficient mold retention time shall ensure that the castings are fully solidified, cooled and have certain strength in the mold. Generally, the shortest time for casting ejection without deformation and cracking is appropriate. Die casting aluminum alloy castings shall be 5S~30S is directly related to the wall thickness of the casting. The thicker the wall thickness of the casting, the longer the mold retention time.