Some products of the injection mold factory are molded with PC (polycarbonate) or PC + ABS materials. Due to the poor fluidity of PC, the process is usually filled with high mold temperature and high material temperature: the gate used is usually point gate, and graded injection molding is required to find the gate position and injection pressure maintaining switching position, It will be very helpful to solve the gate gas mark and flash anomaly.
Therefore, if our injection mold factory wants to make a good mold product, we need to pay special attention to the injection molding process, and in the previous articles, we have also handed in the convenient process of product molding through product design and mold design, and the injection molding process is a key step in the process. We need to pay attention to the setting of molding parameters such as solution temperature, mold temperature, injection speed and back pressure.
1、 Melting temperature and mold temperature
Molding temperature setting is related to many factors, such as the size of injection molding machine, screw configuration, mold and molded product design and molding cycle time. Generally speaking, in order to melt the plastic gradually, set a slightly lower temperature at the rear section / feed of the feed pipe and a higher temperature at the front end of the feed pipe. However, if the screw is not designed properly or the L / D value is too small, the reverse temperature setting is also feasible.
Mold temperature setting skills: high temperature mold can provide a better surface appearance, the residual stress will be relatively small, and it is also good to fill thinner or longer molded products. The advantage of low temperature mold is that it can shorten the molding cycle.
2、 Injection speed
The injection rate is closely related to the design of gate. When using direct gate or edge gate, a slower injection rate shall be applied to prevent sunlight and wave flow mark. In addition, if the thickness of the finished product is more than 5mm, slow injection is helpful to avoid blistering or depression. Generally speaking, the principle of fire speed is that thin is fast and thick is slow.
When switching from injection molding to pressure holding, the pressure holding pressure shall be as low as possible to avoid residual stress of molded products. The residual stress can be removed or reduced by annealing under the condition of 120 ℃ to 130 ℃ for 30 minutes to 1 hour.
The above is how the injection mold factory solves the possible problems of products through the injection molding process. If you want to know more about mold injection molding, you can log in to the official website of pintejin molding, where there are various processing cases for reference, and look forward to your visit!
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