What are the characteristics of plastic injection molding?
Plastic injection molding inherent high heat resistance, excellent electrical properties and deformation resistance, and many other outstanding advantages of more and more people's attention. Used to compress the molding.
But the compression molding production efficiency is low, the product quality is not stable, therefore receives certain limit, cannot satisfy the production development the need. After the 1960s, the plastic injection molding technology was successfully transplanted into thermosetting plastic processing, and was promoted
Its main features are as follows: (1) The advantages of thermosetting plastic injection Molding
1) The temperature of plasticizing is low. Plastic Injection Molding In order to prevent thermosetting plastic in the barrel premature solidification, the material temperature can not be too high, generally controlled in the transition or viscous flow of the initial temperature, and thermoplastic plastic temperature is higher.
2 high production efficiency.
Because the curing period of thermosetting plastics is short, the molding period is shortened greatly, and the production efficiency can be increased by more than 10 times times.
3) facilitates automation. Thermosetting Plastic Injection Molding process is simple, plastic parts easier to repair, easy to automate operation, Plastic Injection Molding so that the production efficiency greatly improved.
4 product quality is stable.
Injection Molding products Density uniformity, good repeatability, quality consistent, more suitable for high-volume production.
5 low production cost. Because of the short production cycle, Plastic Injection Molding high production efficiency and less waste, the total cost is generally lower.
1) high injection pressure. Thermosetting plastics with low plasticizing temperature, large melt viscosity, in order to fully fill the mold cavity, the need to exert a high injection pressure (100~200MPA).
2 processing technology is more complex. Thermosetting plastic is in the heating mold solidification molding, for this reason, thermosetting plastic molding mold needs to be equipped with heating device.
3 waste can no longer be used. The waste produced after the molding of thermosetting plastics is no longer softened when heated and can only be discarded as waste.
4) The forming temperature range is narrow. Plastic Injection Molding The forming temperature is not large, the temperature is slightly lower than the molten material is difficult to flow, and the temperature is slightly higher and its fluidity quickly become smaller or even hardened, so the barrel and nozzle temperature control precision requirements are high, generally in the ±3℃ range.
5 The formation of gas more. As the thermosetting plastic in the occurrence of cross-linking reaction will produce gas, they will have some difficulty in the mold design, because these gases if not timely discharge, will seriously affect the quality of products.