Injection molding problem: Plastic has bubbles

author: Universe plastic

2024-04-10

In injection molding manufacturing, bubbles inside plastic products are a common injection molding problem, especially transparent plastic injection molding, which will seriously affect the appearance and performance of the product.

In this article, Universe Plastic Engineer will introduce in detail how to avoid the occurrence of injection bubbles during the injection molding production process:

Improve injection molding materials

1. Injection molding materials with good fluidity are conducive to filling the mold cavity and reducing the generation of bubbles.

2. Injection molded plastic materials need to be fully dried. The water vapor inside the plastic will be converted into steam at high temperatures, resulting in the formation of bubbles.

Check and optimize mold design

1. Optimize the exhaust system of the mold to prevent air from being trapped in the mold during the injection molding process. You can add exhaust slots or exhaust holes.

2. Improve the design of the gate location and size to ensure that the material can flow into the mold smoothly and avoid the formation of bubbles.

3. After each injection molding, check whether the injection mold cavity is clean and free of foreign matter and plastic residue, otherwise bubbles may occur.

Adjust injection molding parameters

1. Appropriately increase the injection pressure and reduce the injection speed to help fully fill the mold and discharge the air.

2. Adjust the temperature of the plastic melt. Too high or too low a temperature may cause bubbles to form.

3. The mold temperature should be moderate. Too low a mold temperature will cause the melt to cool too quickly and prevent bubbles from being discharged.

4. Properly extend the holding time to ensure that the melt is fully filled in the mold and that there is enough pressure to expel bubbles during the solidification process.

5. Use a multi-stage injection molding process to adjust the injection speed and pressure according to different parts of the product so that the melt can fill the mold more evenly.

Check injection molding equipment

1. Regular maintenance and upkeep of injection molding equipment, such as cleaning the injection molding machine and checking the injection molding system, can avoid the generation of bubbles.

Other methods

1. Use a vacuum system during the injection molding process to extract the air from the mold cavity to effectively prevent the generation of bubbles.

2. The low-pressure injection molding process can reduce the air content in the melt and reduce the risk of bubbles.

3. Through quality control and inspection of product appearance, bubble products can be discovered in a timely manner and problems can be eliminated step by step.

Summarize

In order to avoid the generation of plastic bubbles, corresponding measures need to be taken in all aspects of injection molding.

Through reasonable material selection, mold optimization, injection molding parameter adjustment and other factors, bubbles can be effectively avoided and the quality and appearance of the product can be improved.

Dongguan Universe Plastic Company has more than 15 years of injection molding experience. If you have injection molding needs, you can contact us for more solutions.

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