How to Maintain Fluidity when the Compound is Injected?

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High-gloss injection molding technology is also known as rapid thermal cycle injection molding technology.

 

High-gloss injection molding technology is also known as rapid thermal cycle injection molding technology. Using this technology, any shape of the mold surface can be well replicated, so that the surface of the product has no melting marks, and the surface highlights can achieve a mirror effect; improve the strength and surface hardness of the plastic part; make thin walls Molding improves the fluidity of injection molding, improves product quality and strength; reduces the injection cycle of thick-wall molding by more than 60%; does not require subsequent spraying processes with serious environmental pollution, which can reduce process flows and save energy and materials.

In this way, the cost of plastic products can be directly reduced, and the environment and the personal health of operators can be better protected.

The process principle of high-gloss injection molding:

The mold is heated before and during the mold clamping process. After the mold is closed, the injection is performed when the temperature reaches the set condition. During the injection process, the mold continues to maintain a high temperature, so that the rubber compound can maintain a good fluidity in the mold when it is injected. After the injection is completed, when the pressure is maintained and cooled, the mold is cooled, which can greatly shorten the cooling time of the product, thereby improving the production efficiency.

The traditional method is to use a mold temperature machine to heat the mold, but the shortcomings of this method are as follows:

1. Can not meet the needs of rapid heating and rapid cooling in high-gloss injection molding;

2. The temperature rise is small, and the weld line on the surface of the product can only be reduced but not eliminated;

3. As the plastic hardness is higher, the fluidity is worse. Therefore, the hardness of the surface of the product using this process can only reach the HB level, which cannot meet the actual user needs;

4. The mold expands when it heats up and shrinks when it cools down, making the clamping force very unstable. It is easy to cause various defects such as dissatisfaction, scorching, and large internal stress on the product.

The steam high-gloss injection molding technology developed on the basis of this process has been improved for the above defects:

1. In this technology, a water pipe is opened in the mold, steam is passed when heating is required, and cold water is passed when cooling is required. After cooling, the residual moisture can be blown out with compressed air to ensure rapid heating and cooling;

2. To maximize the elimination of various product failures such as weld line clips, watermarks, and lack of glue;

3. Due to the large temperature rise, the use of H or even 2H hardness level plastics greatly improves the surface hardness of the product;

4. Since the inner surface of the mold is only heated or cooled when the pipe is opened inside the mold, the overall expansion of the mold is small, thus reducing various product defects caused by the instability of the clamping force.

Ningbo Salai machinery co., Ltd. is an Injection Molding Machine Manufacturer and other products such as Plastic Molding Machines, welcome to visit our official website.

 

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