How is There Air Bubble in the Cross Section of Extrusion Layer?

Various quality defects may appear in the process of plastic extrusion. One of them is that there are bubbles in the cross section of extrusion cladding. So, how should we deal with this situation?
The reason of air hole or air bubble on the cross section of extrusion cladding layer is as follows:
1. The temperature control is too high (especially in the feed section);
2. There is moisture in the plastic;
3. After parking for a long time, the decomposed plastics were not completely removed;
4. The humidity of natural environment is high;
5. There is water in the cable core or the content of gasification is too high.

In view of the above reasons, we can carry out targeted inspection and solution. The details are as follows:
1. The temperature of each section of screw should be controlled reasonably;
2. Pre dry the materials in advance;
3. Strict process operation requirements, improve the ability to judge the degree of plastic plasticization;
4. Pay attention to the production environment and material storage conditions.

Note:
1. The extrusion dimension is not qualified, which is mainly manifested as core deviation; the sheath thickness or outer diameter is out of tolerance;
2. The unqualified appearance of extrusion is mainly manifested as scratch on the surface of extrusion layer, rough with trachoma or microcrack, and any defect caused by insufficient plasticization.