Two-color injection molding products production process characteristics

1. The two-color injection molding machine is composed of two sets of plasticizing injection devices with the same structure and specifications. The nozzle should have a special structure according to the production method, or it is equipped with two component molds that can rotate and transpose the same structure.

Plasticizing injection, the two sets of plasticizing injection device molten temperature, injection pressure, injection molten amount and other process parameters are the same, to minimize the fluctuation of process parameters in the two sets of devices.

2. Compared with ordinary injection molding plastic products, the melting temperature and injection pressure during injection should use higher parameter values. The main reason is that the mold flow channel in the two-color injection molding is relatively long, the structure is more complex, and the flow resistance of the injection molten material is larger.

3. Two-color injection molding plastic products should choose raw materials with good thermal stability and low melt viscosity to avoid decomposition due to high melt temperature and longer residence time in the flow channel. The most widely used plastics are polyolefin resins, polystyrene and ABS materials.

4. Two-color plastic products in injection molding, in order to make two different colors of molten material in the molding can be well fused in the mold, to ensure the molding quality of injection products, should be used higher melting temperature, higher mold temperature, higher injection pressure and injection rate.

Two-color mold structure

The traditional two-color injection mold has two forms of "punch translation" and "punch rotation".

¢Ù The mold of "punch translation" has two concave dies and one punch. When the first barrel shoots glue, the punch is closed with the first concave die. Finish the injection of the first plastic. After the first plastic sets, the concave and punch separate, and the semi-finished product formed by the first plastic stays in the punch and moves with the punch to align with the second punch. After the injection molding machine is closed, the second cylinder is injected with the second kind of plastic. After the second kind of plastic solidifies, the injection molding machine opens the mold and takes out the complete product.

¢Ú The two-color mold in the form of "punch rotation" has two concave dies and a punch composed of two back-to-back combinations, which can be rotated. The two sides of the injection molding machine equipped with two cylinders, the second cylinder is best designed in the direction of the injection molding machine movement in the vertical direction. Two different plastics can be injected at the same time. When the two types of plastic are solidified, the injection molding machine opens and automatically ejects the complete product. After the product is removed, the "rotatable punch" is turned 180 degrees. The injection molding machine closes for the next cycle.

Because the first and second cylinders of the "punch translation" mode are injected in turn, and the first and second cylinders of the "punch rotation" mode are injected at the same time. Therefore, the same product, the efficiency of production by "punch rotation" mode is twice that of production by "punch translation" mode.

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