00Manufacturer of automatic injection molding plastic parts equipment and machinery for lighters

The injection speed is set for the molding process of the injection molding machine: the injection speed is slow, the plastic is carried out in the mold cavity, there will be more heat loss, the flow viscosity will increase, and the service pressure loss will increase; Higher firing rate can often obtain molded products with higher precision and less deformation. Only through areas such as small meat thickness, fierce change and corner, it is easy to have poor appearance, poor exhaust, batch front and incorrect pressure holding switching.
Switching of molding process setting and pressure maintaining of injection molding machine: if the switching is too early, the finished product size is easy to be insufficient, and even short shot and surface depression occur. On the contrary, it will form excessive compression. If it is small, the size is too large, flash, whitening and deformation, and if it is large, the mold will be damaged; Pressure maintaining switching is usually controlled by injection stroke (position), time, etc.
Set the holding pressure for the molding process of the injection molding machine: if the holding pressure is too high, overfilling will occur, which will reverse the flow of plastic that has entered the mold cavity; The correct and appropriate pressure holding setting should be based on the principle that the screw can continue to advance to the lower pressure of the target point after passing the pressure holding switching point; In the holding stage, the pressure in the mold cavity decreases gradually due to the cooling of the plastic, so the pressure holding should be adjusted appropriately, otherwise it is easy to form high stress residue.
Set the pressure holding time for the molding process of the injection molding machine: the pressure holding time should be maintained until the gate condenses. It is meaningless for too long, but if the time is too short, it is easy to reverse flow, making the position near the gate easy to sag and insufficient size; Whether the holding time is appropriate or not should be judged by the stability of weight; The gate is small, the mold temperature is low, and the pressure holding time should be set shorter. If the situation is opposite, the time should be set longer.
Set the cooling time for the molding process of the injection molding machine: the plastic is cooled in the mold cavity. Most of them start at the end of pressure holding switching and open the mold. The theoretical cooling time = pressure holding time + Post cooling time; The required theoretical time shall be based on the principle that the product can be pushed out smoothly (without deformation), and its length varies with the thickness, material and die cooling speed of the formed product; Gate thickness and mold temperature will affect the holding time (the cooling time set by the machine, that is, the post cooling time). If the gate is large and the mold temperature is high, the holding time shall be appropriately extended, otherwise, the holding time shall be appropriately reduced.
Set the mold temperature for the molding process of the injection molding machine: if the mold temperature is set too low, the melt glue flows in the mold cavity and the temperature drops rapidly, which increases the material flow resistance, so the pressure loss increases, increases the internal stress and increases the pressure in the mold cavity.
High mold temperature is set for the molding process of the injection molding machine: increase the crystallinity and more uniform structure of the molded product, reduce the residual internal stress, deformation and improve the strength, reduce the flow resistance of the material during filling, reduce the pressure loss, and make the product have good appearance luster, but it is prone to burrs, increase the near gate part and reduce the depression at the far gate part, so as to reduce the bonding line, Increased cooling time.