The Points Of The Injection Molding Process Of Bakelite

Bakelite injection molding is basically the same as injection molding of other raw materials. The bakelite powder is melt-plasticized by screw to make it into a molten state and has fluidity. Then, the bakelite melt is injected into the mold cavity by the propulsion system, and cooled by cooling. After that, it becomes the final product. The general process points are as follows:

 1. The temperature control of the barrel generally adopts multi-stage temperature control mode.

 A, two sections of temperature control: the front section 90-95 ° C, the latter section 75-85 ° C;

B, three sections of temperature control: the front section 90-100 ° C, the middle section 80-90 ° C, the latter section 70-80 ° C;

C. If it is injection molding of complex workpieces, adjust the plasticizing temperature according to the specific conditions and injection cycle;

2, back pressure control

 The injection pressure of bakelite is generally between 3-5 kb/cm2, and it can be produced according to different products and product structures by selecting appropriate pressure. The bakelite is converted into a fluid state by plasticization, and the fluid is injected into the cavity by using a suitable back pressure. Since the fluidity of the bakelite melt is good, there is no special requirement for the injection back pressure, and a uniform and stable injection is maintained. The pressure is enough.

 3, injection speed

 The injection speed of bakelite is mainly at medium speed. Due to good fluidity, Bakelite injection does not require a particularly high injection pressure, and can be pressed at a pressure of about 60 kg. Use medium-speed injection, the flow rate of 10-25 grams per second can be, if the injection speed is too fast, it will cause friction and heat generation of the bakelite melt and nozzles, runners, gates, cavities, etc., causing melting If the temperature of the material is too high, decomposition and bubble generation will occur; if the temperature is too slow, the production efficiency will be affected, and the melt will remain in the barrel for too long and cause unnecessary loss.

 4, mold temperature control

 Bakelite has a faster forming speed. When the mold temperature drops below 70 °C, it begins to form. It is usually molded at a mold temperature of 40 ° C. The period of molding is related to the wall thickness of the product, with a period of 14 seconds per mm thickness. Set up, the general product curing cycle can be between 50-80 seconds.

  Bakelite injection has no very special requirements for process requirements, and is also relatively friendly in product design. There is no point that requires special attention. Even so, the pace of improving the efficiency of Bakelite injection is not stopped.