A standard injection molding machine can be used to produce a variety of thin-walled products. At present, the performance of the new injection molding machine greatly exceeds that of 10 years ago. The progress in materials, gating technology, and design has further expanded the performance of standard injection molding machines for filling thin-walled parts. But due to the continuous reduction of wall thickness, a more special injection molding machine with high-speed and high-pressure performance is needed. For example, it is normal for an electronic component with a thickness less than 1mm to have a filling time of less than 0.5 seconds and an injection pressure exceeding 210MPa.
The hydraulic injection molding machine used for thin-walled injection molding is designed with a pressure reservoir, which can frequently drive injection molding and mold closing. In order to withstand the high pressure of the new injection molding machine, the minimum value of the locking force must be 5-7 tons/inch (projected area). In addition, when the wall thickness decreases and the injection pressure increases, a large template helps to reduce bending. The ratio of the pull rod of the injection molding machine used for thin-walled products to the thickness of the template is 2:1 or lower. When producing thin-walled products, the closed-loop control of injection molding speed, pressure, and other processing parameters helps to control mold filling and pressure holding under high pressure and high speed.
As for the injection volume, large diameter machine barrels are often too large. The recommended injection volume is 40% to 70% of the machine barrel capacity. The total molding cycle of thin-walled products is greatly shortened, and it is possible to reduce the minimum injection volume to 20% to 30% of the machine barrel capacity. Users must be very careful when injection molding, because for materials, a small injection volume means that the material stays in the barrel for a longer time, which can lead to a decrease in product performance.
