How to remove bubbles after thick sheet vacuum forming processing?

Bubbles are a common problem in the thick sheet vacuum forming process, which can affect the appearance and quality of the product. The following are some commonly used methods to remove air bubbles from thick sheet vacuum forming products:

Optimize the parameters of vacuum forming

Adjust the heating time and temperature to ensure that the plastic sheet is fully softened so as to better adhere to the mold.

Increase the vacuum intensity to ensure that the sheet material can be closely adhered to the mold.

Improve mold design

Make sure the surface of the mold is smooth without any unevenness or sharp edges, which can reduce the formation of bubbles.

A well-designed exhaust system enables the gas on the surface of the mold to be discharged smoothly.

Process adjustment

During the vacuum forming process, the vacuum forming speed can be appropriately reduced to allow more time for the gas to be discharged.

For complex shapes, vacuum forming can be carried out step by step. First, vacuum form the main parts, and then handle the details to reduce air bubbles.

Physical method

Use a needle or a small tool to gently puncture the bubble, and then use a vacuum cleaner or vacuum pump to extract the gas.

Gently apply pressure to the bubble to burst it and make the material adhere.

Heating treatment

For some bubbles that are not easy to burst, you can appropriately heat the local area to soften the material, and the bubbles will naturally disappear.

Local heating of the bubble area with an infrared heater helps eliminate the bubbles.

Use defoaming agent

Before vacuum forming, a special defoaming agent can be applied to the plastic sheet to help reduce the formation of bubbles.

Post-processing

For bubbles that cannot be removed by the above methods, grinding or painting treatment can be carried out after the product is formed to cover the bubbles.

The key to removing bubbles lies in prevention. By optimizing process parameters, improving mold design and using appropriate equipment, the generation of bubbles can be largely reduced. For the bubbles that have already formed, corresponding measures need to be taken according to the specific circumstances to eliminate them.